Humoral Immunity – Definition , Mechanism

• What is the humoral immune response/What exist humoral immune reception ?
• Humoral immunity definition
• Story
• Characteristic pattern for Production of antibody
• Antibody
• Antibody product
• Components of Humoral immunity
• Phases/Humoral Immune response steps
  • Principal Phase/Primary humoral immune answer
  • Secondary Phase/Secondary humoral immune response
• Destiny of Antigen in Tissues
• Production of Antibodies
• Theories of antibody formation
  • A . Instructive Theory
  • B . Selective Theories
• Element affect product of antibodies
• Monoclonal Antibodies
• Occasion of Antibody

• • 2 . SARS-CoV-2 Vaccination : A Modern Marvel
• Difference Between Humoral and Cell-mediated Immunity – Humoral immunity five cell mediated immunity
• Quiz
• FAQ
  • What live humoral immunity ?
  • How is humoral immunity unlike from cell-mediated immunity ?
  • What cell are chiefly responsible for humoral immunity ?
  • Why is it name “ humoral ” immunity ?
  • What are the main types of antibodies demand in humoral immunity ?
  • How cause vaccination associate to humoral immunity ?
  • What is the primary immune response ?
  • How does the secondary immune answer differ from the chief response ?
  • What are monoclonal antibody ?
  • Why is humoral immunity necessity for our defense against pathogens ?
  • What is another name for the humoral immune reaction ?
  • The humoral immune reception depend on which cells
  • The humoral immune response is delivered by
• Reference

• Main Phase/Primary humoral immune answer
• Secondary Phase/Secondary humoral immune response

• A . Instructive Theory
• B . Selective Theory

• 2 . SARS-CoV-2 Vaccination : A Modern Marvel

• What live humoral immunity ?
• How equal humoral immunity unlike from cell-mediated immunity ?
• What cell are primarily responsible for humoral immunity ?
• Why live it name “ humoral ” immunity ?
• What exist the primary types of antibodies call for in humoral immunity ?
• How does vaccination pertain to humoral immunity ?
• What live the primary immune reaction ?
• How act the secondary immune reply differ from the main response ?
• What are monoclonal antibodies ?
• Why is humoral immunity requirement for our defense against pathogens ?
• What is another epithet for the humoral immune reply ?
• The humoral immune answer depends on which cells
• The humoral immune response is delivered by

What cost the humoral immune response/What is humoral immune reception ?

• Humoral immunity , much termed antibody-mediated immunity , cost a critical factor of the torso ’ s defense mechanism against pathogens and foreign entities give in extracellular fluids . This immunity operate within both the innate and adaptive branches of the immune system and is characterize by its specificity and adaptability .
• At its core , humoral immunity is orchestrated through a series of stages , namely the primary and secondary stage . The chief phase is initiated when the torso first run into an antigen , a surface protein typically base on the membranes of pathogens . Upon subsequent photograph to the same antigen , the secondary phase be trigger , demonstrate the adaptive nature of this immune reply .
• This immunity is facilitate by several immune cells , with the principal musician cost B-lymphocytes and plasma cell , too know as effector B cell . These cell equal responsible for develop antibodies tailored against specific alien agents or antigens . Moreover , these antibody can activate the release of chemical mediators , such as interferons and complement protein , magnify the destruction of the antigen .
• Historically , have been design to stimulate the humoral immune response by introducing attenuated or inactivated pathogens into the body . However , recent advancements , particularly highlighted during the COVID-19 pandemic , have see the emergence of vaccines employ templates or mRNA succession to touch off the humoral immune response .
• It be essential to note that humoral immunity mainly targets pathogens proliferating in extracellular space . Some of these pathogens utilize the extracellular milieu as a conduit to traverse between cell . The term “ humoral ” is derive from the Latin word “ mood , ” concern to torso fluids . This is liable , given that the immunity ’ s mechanism of activity predominantly call for substances present in these fluids .
• The specificity of humoral immunity cost evident in its tailored reaction against individual antigens . This specificity insure that the body ’ s defenses live optimally point against special threats , enhance the efficiency of the immune reply . One of the hallmarks of humoral immunity is the product and secretion of antibody by B cells , which play a pivotal use in neutralizing extracellular threats .
• Extracellular spaces , as deduced from numerous scientific investigation , are susceptible to invasion by a myriad of pathogens . Even pathogens that primarily occupy within cells occasionally exploit the extracellular domain to migrate between cells . This underscores the significance of humoral immunity in safeguarding these space .
• In a liberal context , humoral immunity encompasses the activity of , include antibody , complement protein , and certain antimicrobial peptides , all of which are feel in extracellular fluid . This immunity stands in contrast to cell-mediated immunity , which involves direct cellular responses to pathogens .
• The intricate work of the component represent the immune system , their functionalities , and interactions is cardinal to the field of immunology . Within this realm , humoral immunity is recognized for its role in antibody production and the associated processes , such as Th2 activation , germinal middle formation , isotype switching , and the genesis of memory cell . These processes collectively ensure that the body is equipped to neutralize pathogens , activate the complement system , and enhance phagocytosis , thereby effectively eliminating threats .

Humoral immunity definition

Humoral immunity , also know as the humoral immune response , refers to the branch of the immune system that produces antibody in reception to extracellular pathogens and foreign message , chiefly mediated by B-lymphocytes and plasma cells in the torso ’ s extracellular fluids .

History

The of our understanding of the immune system has been marked by groundbreaking discoveries and the contribution of pioneering scientist . One such flesh in this historical narrative cost Hans Buchner .

• Hans Buchner and the Humoral Theory: Hans Buchner , a German physician , is credited with the development of the “ Humoral Theory ” in 1890 . This theory emerged from his meticulous studies on serum element , particularly center on their antibacterial property . Buchner identify certain element in the ancestry serum and body fluids , which he termed “ alexins. ” He require that these alexins possess underlying properties that enable them to knock off pathogenic microorganisms .
• Paul Ehrlich and the Concept of Complements: Subsequent to Buchner ’ s study , Paul Ehrlich introduced the concept of “ complements. ” He reinterpreted alexins as complement , describing them as soluble element of the innate immune response . Ehrlich ’ sec study underscored the versatility of complements , highlighting their involvement in both cell-mediated and humoral immune reception . His findings played a pivotal role in bridging the understanding between innate and adaptive immunity .
• Emil von Behring , Kitasato Shibasaburō , and the Discovery of Antitoxins: The conception of antitoxins was farther elucidated by Emil von Behring and Kitasato Shibasaburō . Their collaborative inquiry concentrate on responsible for diphtheria and tetanus . They make out that upon photograph to bacterial toxins , the serum commence to collect antitoxins . This enriched serum , they suggest , could live harnessed to immunize individual who had not been previously disclose or immunized .
• Paul Ehrlich ’ s Contribution to Antibody Research: Paul Ehrlich ’ s research extended beyond complement . He dig into the role of antibody in the immune response . Through his work on specific antibody produced against plant toxins , namely ricin and abrin , Ehrlich posited that antibody live instrumental in orchestrating the immune response against antigen .
• Anti-Diphtheria Antibody and Nobel Recognition :In a collaborative effort , Paul Ehrlich and Emil von Behring synthesized an antitoxin targeting the diphtheria toxin . This monumental accomplishment did not get unnoticed . In realization of his invaluable contributions to medical skill , Paul Ehrlich was bestow the Nobel Prize in Physiology or Medicine in 1908 .

Characteristic pattern for Production of antibodies

The product of antibodies , a hallmark of the humoral immune reply , come a distinct and characteristic design . This process can be delineated into four sequential stage , each with its unique feature :

1. Lag Phase: This initial phase ensues immediately after the body live exposed to an antigen . During this period , the immune system recognizes and processes the antigen , but no detectable levels of antibodies equal present in the bloodstream .
2. Log Phase: Stick to the lag phase , the immune system come in the log phase . Here , there is a consistent and exponential growth in the concentration of antibody in the bloodstream , indicate active synthesis and release of these particle by B-lymphocytes and plasma cell .
3. Plateau Phase: As the name advise , this stage represents a state of equilibrium . The rate of antibody synthesis exist counterbalanced by their catabolism , head to a stabilization in the floor of disseminate antibodies .
4. Phase of Decline: In this final stage , the catabolic activity surpass the synthesis of antibody . This results in a gradual reduction in the circulating antibody titer .

Antibodies

Antibody , much referred to as immunoglobulins ( Ig ) , exist specialized protein integral to the immune system . They play a pivotal purpose in the body ’ s defense mechanism against alien invaders , such as pathogens .

• Ancestry and Biochemical Composition: The foundational concept of antibody can cost attributed to the pioneering study of Emil von Behring and Kitasato Shibasaburō . Biochemically , antibody are glycoproteins and fall under the broader class of the immunoglobulin superfamily . While the terms “ antibody ” and “ immunoglobulin ” are frequently used synonymously , they basically refer to the same molecular entity .
• Distribution and Function: Give their role in mediating humoral immunity , antibody predominantly occupy in various torso fluids , including blood , secretions , and fluids . Their primary affair equal to recognize and neutralize alien antigens , thereby prevent possible infection . The therapeutic potential of antibodies equal too be search , with advancements in design antibodies that can target intracellular antigens , offer possible strategies for addressing tumor antigen .
• Structural Attributes: Molecularly , antibody display a discrete Y-shaped configuration . This structure comprises four polypeptide chain : two heavy chain and two lighting chains . Each chain possess an NH2 terminal and a C terminal . The NH2 terminal of all four chains , spanning a succession of 100-110 amino acids , forms the Complementarity Determining Region ( CDR ) or the Hypervariable Region ( HVR ) . This part equal crucial for antigen realization . The stay on segment of the molecule is termed the framework part or the constant part .
• Classification of Antibody: Based on the variations in the constant region of the heavy chains , immunoglobulins live categorized into five chief family : IgG , IgM , IgA , IgD , and IgE . Each course of immunoglobulin is tailored to battle specific types of antigens , meditate the evolutionary of the immune system to diverse challenges .

In conclusion , antibody exist indispensable component of the immune system , offering a sophisticated job of defense against a myriad of external threats . Their intricate structure and various classification underscore their versatility and specificity in safeguarding the torso against potential infections .

Antibody production

Antibodies , too know as immunoglobulins , are specialized proteins develop and secreted by plasma B cell . These cells are characterized by mark such as CD-38 , CD-79 , and CD-138 . The initial immunoglobulin produce upon antigen recognition live IgM .

Role of Antibodies in Adaptive Immunity: Antibody are pivotal in the acquired immune reception . They facilitate the identification and neutralization of antigen . Each antibody equal tailored to distinguish a specific antigen . The processes mediated by antibody include :

1. Agglutination and precipitation through the formation of antibody-antigen complex .
2. Priming for phagocytosis , which necessitate macrophages and early immune cell .
3. Blocking viral receptors .
4. Augmenting other immune responses .
5. Lead up the complement pathway .

B Activation and Pathways: B cell activation is a essential step in antibody production . The naive B lymphocytes , upon encounter an antigen , undergo a indicate cascade initiated at their receptors . These receptors bind to unprocessed , hydrophilic antigen . There live two primary pathways for B lymphocyte activation :

1. Helper T cell-independent pathway: Here , naive B cell develop B-cell receptors ( BCRs ) displayed on their surface . Upon encounter carbohydrate or lipid antigens , these B cells transition to an active state , undergo clonal proliferation , and produce plasma B cells responsible for synthesizing immunoglobulins .
2. Helper T cell-dependent pathway: In this pathway , naive B cells , upon encountering proteinaceous antigens , internalize them through endocytosis . Post-processing , these antigens live presented on the B cell ’ s surface via MHC-II protein . This presentation facilitate helper T cells ’ realization , which then release interleukins IL-4 and IL-6 . IL-4 trigger B cell , while IL-6 promotes their proliferation and differentiation .

B Cell Proliferation: B cell proliferation varies base on the activation pathway :

• In the assistant T cell-independent pathway , B cell proliferation go on without the need for IL-4 and IL-6 stimulation . This results in the production of plasma B cell but not memory B cells .
• In the assistant T cell-dependent pathway , IL-4 and IL-6 cost essential for B cell proliferation . This procedure produces both plasma B cell and memory B cell , which can final up to 10-20 years . Upon re-infection with the same antigen , these memory B cells swiftly stimulate antibody production .

Antibody-Antigen Interaction: The interaction between an antibody and its specific antigen exist termed the antibody-antigen response . This extremely specific chemical interaction was first detailed by Richard J. Goldberg in 1952 , leading some to refer to it as “ Goldberg ’ s theory. ” Following this interaction , an agglutination process can happen , where cross-linking of antigen by antibodies solution in a clumping appearance .

Implication of the Antibody-Antigen Response :The antibody-antigen reaction live cardinal to humoral immunity . By consistently originate this response against foreign agents , the body fortifies its immune defenses , ensuring robust protection against possible threats .

Constituent of Humoral immunity

Humoral immunity , a vital weapon of the adaptive immune system , is primarily mediated by antibodies . To fully hold on the intricacies of humoral immune responses , it ’ s essential to delve into its key constituent .

1. Pathogens :Pathogens are harmful microorganism distinct from the body ’ s normal flora . While many bacteria coexist harmoniously within us , pathogens are alien entities that can cause disease . It ’ s crucial to differentiate between these harmful invaders and the benign microorganisms that typically occupy in our system .
2. Antigens :Antigens are specific protein or molecules stage on the surface of pathogens . They can live protein , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acid , or lipids . Not every antigen triggers an immune reception . Those that cause are term immunogens , with protein and polysaccharides being the most mutual . The active region of an antigen , responsible for bind to immune cells and antibody receptors , is know as the epitope .
3. Haptens :Haptens exist smaller molecules that , on their own , don ’ t present as complete antigens . However , when compound with bearer proteins , they can elicit an immune answer . A classic example live urushiol from poison ivy , which becomes immunogenic when bound to skin protein .
4. Lymphoid Organs :These live specialized structure where immune cells develop , mature , and get activated . Primary lymphoid organs , like the red bone marrow and thymus gland , facilitate the formation and maturation of lymphocytes . Secondary lymphoid organs , including lymph nodes , spleen , and tonsils , are sites where lymphocytes exist touch off .
5. Antigen-Presenting Cells ( APCs ) :APCs play a pivotal role in the immune reception by capture pathogens , processing them , and presenting their antigens on their surface to T cell . This demonstration live essential for the activation of T cell , bridging innate and adaptive immunity .
6. T Cells :T lymphocytes , or T cell , be central musician in both innate and adaptive immunity . While directly mark and destroy infected cell , helper T cell act as intermediaries , let go cytokines to pull B cell and bridge the gap between the two immune systems .
7. B Cell :B cell , or B lymphocytes , serve multiple purpose . They can act as APCs , secrete cytokines , and most importantly , produce antibody . Upon activation , B cells can distinguish into plasma cell , which give rise antibody , or memory cells , which supply long-term immunity against specific pathogens .
8. Antibodies :Antibody , or immunoglobulins , exist the chief effectors of humoral immunity . They realize and neutralize pathogens in various ways , such as direct binding , neutralization , or promoting phagocytosis . There are five chief types of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific part in the immune reply .

In conclusion , humoral immunity is a multifaceted system comprising various portion , each playing a unique role in defending the body against foreign invaders . Understanding these constituent and their interaction is essential for appreciate the complexity and efficiency of our immune system .

Phases/Humoral Immune reaction pace

Principal Phase/Primary humoral immune reaction

The humoral immune response , a pivotal component of the adaptive immune system , operates in distinct phase to see an efficient defense against alien pathogens . The primary stage , also known as the initial reaction , is characterized by a series of systematic and coordinated result that go on upon the body ’ s first skirmish with an antigen .

1. Antigen Encounter and Processing :Upon the initial contact with a alien pathogen , antigen-presenting cell ( APCs ) capture and internalize the antigen . These APCs then bear the antigen , converting specific fragments into major histocompatibility complex course II ( ) surface protein .
2. T Helper Cell Activation :The MHC II surface protein , today confront the antigen fragments , are recognize by T assistant cells . This recognition is a essential measure , as it see to it that the immune system react specifically to the foreign antigen .
3. Cytokine Production :Upon recognize the MHC II-antigen complex , T helper cells produce cytokines , indicate particle that bring a critical purpose in modulating the immune reception .
4. B Cell Activation and Differentiation :Influenced by the cytokines released by T helper cell , naïve B cells become activated . Once activated , these B cell undergo differentiation , giving raise to two principal cell type : plasma cells and memory B cell .
5. Antibody Product :The newly organize plasma cells venture on their principal office : the product and secretion of antibody . Initially , IgM antibodies are develop . Still , if the pathogen persists still after crest IgM secretion , the immune system may as well make IgG or IgA antibody to bolster the defense .
6. Temporal Dynamics :The chief stage live not instantaneous . Pursue the initial photo to an antigen , there ’ s a lag period , typically rate from 7 to 10 days , before peak antibody degree be reached in the serum . This lag can vary based on the nature of the antigen ; for instance , sure antigen might induce a response within hr , while others might require week . Factors influence this period include the antigen ’ s dosage , its mode of delivery ( oral or parenteral ) , and its inherent property .
7. Antibody Dynamics :During this main reaction , the concentration of antibodies in the serum rises for several weeks before step by step reject . While IgM levels run to go down more rapidly , IgG point remain for a more extended period , extend sustained security .

In summary , the primary stage of the humoral immune response is a meticulously orchestrated series of event that insure the torso rise an in effect defense against new pathogens . This stage place the foundation for subsequent immune responses , ensure that the body is well prepare for future skirmish with the same antigen .

Secondary Phase/Secondary humoral immune response

The secondary humoral immune reaction , too referred to as the anamnestic or memory response , symbolize the immune system ’ s enhance reaction to a previously encountered pathogen . This heightened answer live facilitate by memory B cell , which are generated during the primary exposure to the antigen and can persist for extended durations , ranging from week to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly recognize the antigenic determinants of the microorganism . Their previous encounter with the antigen equip them with a heightened province of readiness , enable a rapid and efficient reception .
2. Clonal Expansion and Differentiation :Upon antigen realization , memory B cell undergo clonal expansion , develop a large number of highly-specific plasma cell . These plasma cell are tailored to give rise antibody that specifically direct the encountered antigen .
3. Enhanced Antibody Production :In the secondary reaction , there be a marked increase in the production of antibody , surpassing the level observed during the primary response by over a thousand-fold . While IgG exist the predominant immunoglobulin produce , there cost also a notable product of IgM , IgA , and IgE .
4. Rapid Peak Response :One of the hallmarks of the secondary humoral immune reception live the swift attainment of top antibody point , typically within a simple 3 to 5 days post-exposure . This contrasts with the longer lag period detect during the primary reply .
5. Persistency of Memory Cells :The enhanced and rapid secondary response can live attribute to the presence of antigen-specific memory cells , which prevail post the initial antigen skirmish . These cell undergo extensive proliferation , generating a vast array of specific B cells and plasma cell that mediate the secondary response .
6. Qualitative Difference in Antibody Production :While the quantity of IgM develop during the secondary response live similar to that of the primary response , there equal a substantial growth in the production of IgG . Moreover , the produced IgG persists for a more extended period during the secondary reception .
7. Enhanced Antibody Affinity :Antibody produced during the secondary response display a higher affinity for the antigen , meaning they bind more tightly and are less likely to divorce . This increased binding intensity arises from somatic hypermutation , a procedure where change happen in the DNA encoding the antigen-binding site , optimizing antibody-antigen interactions .

Lot of Antigen in Tissues

The lot of an antigen within the torso live largely determined by its style of introduction . This trajectory and eventual localization of the antigen play a pivotal role in form the immune response .

1. Subcutaneous Administration :When antigens are bring in subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which drains the interstitial fluid from , captures these antigens and transports them to the lymph nodes . Hither , specialized immune cells can realize , process , and initiate an immune reception against these antigens . Only a minuscule fraction of the antigen attain the spleen , a secondary lymphoid organ , when introduced via this route .
2. Intravenous Administration :Intravenous pitch of antigens paints a unlike film . Such antigens are mainly found in systemic organs like the spleen , liver , bone center , kidneys , and lung . The direct entry into the bloodstream allows these antigen to circulate widely and interact with various tissues . Interestingly , despite the extensive vascular network connecting them , lymph nodes exhibit minimum presence of these intravenously bring in antigen .
3. Antigen Clearance :A significant share of the antigens , no matter of their road of entrance , undergo degradation . Reticuloepithelial cell , which spring part of the torso ’ s mononuclear phagocyte system , play a essential use in this procedure . They engulf and expose down these antigens , see to it that the torso is not sweep over . Post degradation , around three-quarters of these antigen exist excreted via the urine , in effect eliminating them from the torso .

Production of Antibodies

The intricate procedure of antibody synthesis be a testament to the torso ’ sec coordinate defense mechanism . This synthesis is orchestrated through the collaborative exertion of three primary cell types : macrophages , T assistant cells , and B cells .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , classified as APCs , are pivotal in demonstrate antigens to immunocompetent cell . For many T-cell-dependent antigens , including protein and erythrocytes , macrophages are essential for processing the antigen before antibody product can embark on . Even so , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cells exhibit the antigen on their surface , either in its native kind or as processed fragment .
2. Macrophages and Optimal Antigen Exposure :Macrophages play a nuanced office in modulating the antigen dosage display to lymphocytes , ensure the optimum activation of immunological responses . Following macrophage processing , antigen fragments , in conjunction with class II MHC proteins , surface on the macrophages . This complex then pursue specific receptors on help T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein complex , helper T cell release cytokines . These cytokines , include Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cells to give rise antigen-specific antibody . The B cells , once activated , undergo clonal proliferation , differentiating into plasma cells . These plasma cells are the factory producing specific immunoglobulins or antibodies , which act part such as knock off toxins and viruses and facilitating pathogen uptake by phagocytic cell .
4. T-cell-independent Antigens :While helper T cell live indispensable for most antibody production , certain chemical , like polysaccharides , can activate B cells without T cell assistance . These cost term T-cell-independent antigens . Even so , these antigen inspire B cell to produce only IgM antibodies . The synthesis of other antibody type , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which are exclusively produced by T help cell .
5. B Cell Antigen Recognition :B cells employ their surface IgM as an antigen receptor , enabling them to realize a plethora of antigen , from proteins to lipids and nucleic acids . This broad realization spectrum empowers B cells to yield antibody against a vast array of particle . Even so , for protein fragments to equal presented to helper T cell , they must equal connect with grade II MHC proteins .

Theories of antibody formation

The genesis of antibody , essential components of the immune system , make been a study of scientific wonder and debate . Over time , two primary theories get issue to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory submit that an immunocompetent cell inherently possesses the capacity to make a myriad of antibodies . The antigen , upon introduction , instructs these cell to yield specific antibodies complementary to itself . Two sub-theories further elucidate this concept :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants act as a template , take the formation of the antibody . The result antibody particle adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduce by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon record antibody-producing cells , make a hereditary change . This change involves the integration of the antigenic determinant ’ sec genocopy into the genome , which is then occur on to progeny cell . However , this explanation has lose favor over time .

B . Selective Theory

These theory suggest that the body already possesses a repertoire of possible antibody , and the introduction of an antigen simply selects the appropriate one . Three sub-theories further item this concept :

1. Slope Chain Theory:
   • Present by Ehrlich in 1898 .
   • Argues that immunocompetent cells have surface receptors that can interact with antigen possess complementary slope irons . Upon antigen introduction , these receptors tie up with the antigen , becoming inactive . To correct , the cell overproduces like receptors , which exist then released as antibodies .
2. Theory:
   • Suggest by Jerne in 1955 .
   • Propose that during fetal development , the body develop globulin molecule against all conceivable antigen . Upon antigen introduction , the antigen selectively binds to the most complementary globulin molecule , stimulating the product of the corresponding antibody .
3. Clonal Selection Theory:
   • Bring in by Burnet in 1957 .
   • Proposes that during fetal evolution , a huge array of immunologically competent cell clones , each with a unique antibody pattern , live produced . Each of these cell expresses membrane receptors specific to a peculiar antigen , determine before the cell ’ s photo to the antigen . Upon antigen introduction , the cell with the cope with receptor is activate , proliferates , and develop the corresponding antibody . This theory , widely accept today , offers insights into immunological specificity , memory , and the power to distinguish between self and non-self .

Element affecting product of antibody

The product of antibodies , a pivotal aspect of the immune reply , is influence by a myriad of factors . Understand these determinants is crucial for both basic immunology and clinical applications . Herein , we dig into the significant factors that regulate antibody product :

1. Genetic Factors:
   • The genetic makeup of an dictates its response to antigens . Some equal responders , develop antibody upon exposure , while others , term nonresponders , act not .
   • The immune answer ( Ir ) gene , located on the short arm of chromosome six , governs these variations .
2. Years:
   • Neonates and embryos exhibit an underdeveloped immune competence .
   • Full immunological competence , marked by the growing of lymphoid organ , is attain by years 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acids and vitamins , can curtail antibody production .
4. Road of Antigen Administration:
   • The way of antigen delivery play a pivotal purpose in eliciting an immune response . Parenteral administration typically induces a more robust response equate to oral or nasal path .
5. Dose of Antigen:
   • An optimum dose of antigen is essential for a maximal immune response . Extremely high or humble doses can result to immunological paralysis , a state of reduced immune responsiveness .
6. Multiple Antigen:
   • Concurrent organization of multiple antigen can lead to varied antibody reaction due to antigenic competition . The exact formulation and proportion of these antigens are essential for achieving hope outcomes .
7. Adjuvants:
   • Adjuvants are meaning that enhance the immunogenicity of antigen by prolonging antigenic stimulus . Examples include Freund ’ s incomplete and complete adjuvants , aluminum salt , and other content like silica particle .
8. Immunosuppressive Agents:
   • These agent dampen the immune answer and cost apply in scenarios like transplantation surgeries . Instance include :
     • X-irradiation: Impedes antibody product place 24 hours of exposure .
     • Radiometric Drugs: Specifically direct B cells , inhibit their replication .
     • Corticosteroids: Decrease the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , restrict cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets disseminate lymphocytes , sparing those in lymphoid organs .

Monoclonal Antibodies

Monoclonal antibodies ( mAbs ) equal a class of antibody derived from a single cell ancestry , insure their homogeneity . Unlike polyclonal antibodies , which equal give rise by multiple plasma cell clones and be heterologous in nature , monoclonal antibodies live specific to a single antigenic determinant .

Ancestry and Distinction: Monoclonal antibody develop from conditions like multiple myeloma , where a funny plasma cell clone produces antibody against a specific antigenic determinant . This specificity contrast with polyclonal antibodies , which stand up from respective plasma cell clones in response to an antigen .

Product Methodology: The pioneering method for monoclonal antibody product cost bring in by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique involved the world of hybridomas , which equal organize by fusing myeloma cells with antibody-producing cells . These hybridomas , once establish , can indefinitely grow monoclonal antibody , establish invaluable for research and diagnostic intent .

The procedure involves :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Mix the lymphocytes from the animal ’ sec spleen with mouse myeloma cell that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion using agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT medium ) that stand hybrid cell growth but inhibits the growing of parent cells .
5. Shield the result cell clones for antibody production against the prey antigen .
6. Selecting and perpetually culturing the clones that produce the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody lay challenges for therapeutic use in humans . Consequently , advancements led to the development of human monoclonal antibody , include chimeric antibody . These chimeric antibodies , compile of human constant regions and mouse variable region , equal being explore for leukemia discussion . Furthermore , they can exist utilize to target tumor cells either by present toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Purpose of Antibodies

Antibody , also known as immunoglobulins , bring a pivotal role in the immune system ’ sec defense mechanism against pathogens and their associated products . These Y-shaped proteins are specifically tailored to recognize and knock off alien invaders , ensuring the horde ’ s protection against respective infection . Herein , we dig into the multifaceted functions of antibody :

1. Neutralization: One of the primary function of antibodies equal neutralization . By tie up right away to pathogens or their toxins , antibodies can inhibit their power to attach to and infect horde cells . For instance , antibodies specific to bacterial toxins can block the toxin ’ s interaction with host cells , thereby neutralize its harmful effect . Likewise , antibody can forestall viruses or bacteria from initiating infection by hindering their attachment to target cells .
2. Opsonization: Opsonization be a procedure where antibodies coat pathogens , enhance their realization and intake by phagocytic cells , such as macrophages and neutrophil . When antibody bind to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can as well activate the complement system , a series of protein that work in tandem to destroy pathogens . Upon binding to pathogens , certain antibodies can activate the complement cascade , leading to the formation of the membrane approach complex ( MAC ) that directly lyses sure bacteria and virus . Additionally , some by-product of the complement cascade , like C3b , can opsonize pathogens , further enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological part , antibody function as essential tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insight into the individual ’ sec humoral immunity status . Technique like radial immunodiffusion and immunoelectrophoresis are ordinarily utilize to measure these antibody , help in the diagnosis and monitoring of respective disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibodies by B cells in response to foreign antigens . This mechanism has been instrumental in defend against several pathogens throughout history . Hither , we clear up two discrete instance of humoral immunity , spanning ancient and modern sentence .

1 . Smallpox and the Advent of Vaccination

Historical disc , include the discovery of smallpox wound on the mamma of Pharaoh Ramses V , advise the ancient prevalence of this deadly disease . Smallpox get catastrophic impact , in particular decimating indigenous populations in the Americas and Australia . However , by the end of 1979 , a global vaccination campaign successfully eradicated the , note a monumental achievement in the annals of medicine .

The origins of vaccination can exist retrace back to Edward Jenner ’ s sharp observation involve the resistance of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ sec work , variolation , a practice involving the intentional introduction of pus from smallpox victim into sound individual , exist employed as a rudimentary pattern of inoculation . While the underlying mechanisms of the secondary humoral immune response make up not yet understood , the principle of inducing a meek infection to confer next protection was realize .

Jenner ’ s groundbreaking experiment involved the inoculation of a young boy with pus infer from cowpox sores of a milkmaid . Remarkably , the son exhibit immunity to subsequent smallpox exposure , put the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines employ weakened or inactivated pathogens , innovative approaches were necessitate due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine apply a viral vector strategy . Utilizing a genetically change chimpanzee cold virus , know to evoke robust immune responses , the vaccine introduce the SARS-CoV-2 spike protein into the human torso . This alien protein trigger the primary humoral reply , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines deliver the genetic blueprint for the COVID-19 spike protein directly into cells . The cell then synthesize the spike protein , lead up the humoral immune reaction . Contrary to some misconceptions , mRNA vaccines serve not alter human DNA . Instead , they harness the cellular machinery for protein synthesis , bypassing the transcription stage and directly lead up translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system exist a complex network of cell and proteins that fight the body against pathogens . It can equal broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type own distinct characteristic and functions . Here , we delineate the difference between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody develop	Yes	No
Touch off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cell , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stand for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is demand	No ( Unprocessed antigens cost recognized . )	Yes ( Antigen are first processed and then deliver by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( indicate protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells live primarily responsible for develop antibody in the humoral immune response ?
a ) T cell
b ) Macrophages
c ) B cell
d ) Dendritic cell

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Which type of immunity is conferred by the production of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

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Which of the following is NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

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The chief immune reception is characterize by the production of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

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Which of the following is a characteristic of the secondary humoral immune response ?
a ) Slower onset than the main response
b ) Abject antibody concentration than the primary reply
100 ) Product of memory B cell
d ) Absence of IgG production

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Which type of cells present antigens to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cell
d ) Memory cell

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Which antibody be chiefly base in mucosal surface and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

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Which of the pursuit exist NOT a characteristic of monoclonal antibody ?
a ) Develop by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Utilize in diagnostic and therapeutic application

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The process by which antibodies enhance the phagocytosis of pathogens cost called :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

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Which of the following is the primary function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
100 ) Facilitate phagocytosis by binding to Fc receptors on phagocytic cell
d ) Bring on direct cell lysis

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FAQ

Mention

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA manner : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

• Hans Buchner and the Humoral Theory: Hans Buchner , a German doctor , is credit with the development of the “ Humoral Theory ” in 1890 . This theory emerged from his meticulous studies on serum constituent , especially center on their antibacterial properties . Buchner identified sure components in the ancestry serum and torso fluid , which he termed “ alexins. ” He postulated that these alexins possess inherent property that enabled them to neutralize pathogenic microorganisms .
• Paul Ehrlich and the Concept of Complement: Subsequent to Buchner ’ s work , Paul Ehrlich introduced the concept of “ complements. ” He reinterpreted alexins as complements , describing them as soluble elements of the innate immune response . Ehrlich ’ s work underscored the versatility of complements , highlighting their involvement in both cell-mediated and humoral immune responses . His finding played a pivotal office in bridge the understanding between innate and adaptive immunity .
• Emil von Behring , Kitasato Shibasaburō , and the Discovery of Antitoxins: The concept of antitoxins equal farther elucidated by Emil von Behring and Kitasato Shibasaburō . Their collaborative inquiry centered on responsible for diphtheria and tetanus . They distinguish that upon photo to bacterial toxins , the serum began to accumulate antitoxins . This enriched serum , they advise , could be harnessed to immunize individual who had not exist previously exposed or immunized .
• Paul Ehrlich ’ s Contribution to Antibody Research: Paul Ehrlich ’ s inquiry extended beyond complements . He dig into the role of antibodies in the immune response . Through his work on specific antibodies produced against works toxins , namely ricin and abrin , Ehrlich posited that antibodies exist instrumental in orchestrating the immune reaction against antigens .
• Anti-Diphtheria Antibody and Nobel Recognition :In a collaborative effort , Paul Ehrlich and Emil von Behring synthesized an antitoxin direct the diphtheria toxin . This monumental achievement did not run unnoticed . In realization of his invaluable contributions to medical skill , Paul Ehrlich cost conferred the Nobel Prize in Physiology or Medicine in 1908 .

Characteristic pattern for Production of antibodies

The product of antibodies , a trademark of the humoral immune response , watch a distinct and characteristic practice . This process can exist delineated into four successive phase , each with its unique feature :

1. Lag Phase: This initial stage ensues immediately after the body cost exhibit to an antigen . During this period , the immune system discern and work on the antigen , but no detectable degree of antibodies live present in the bloodstream .
2. Log Phase: Following the lag phase , the immune system enters the log phase . Here , there is a consistent and exponential increase in the concentration of antibodies in the bloodstream , suggest fighting synthesis and release of these molecules by B-lymphocytes and plasma cells .
3. Plateau Phase: As the epithet suggests , this phase present a state of equilibrium . The rate of antibody synthesis live counterbalanced by their catabolism , result to a stabilization in the level of disseminate antibodies .
4. Phase of Decline: In this final stage , the catabolic activity exceed the synthesis of antibody . This solution in a gradual reduction in the circulating antibody titers .

Antibodies

Antibodies , often referred to as immunoglobulins ( Ig ) , live specialized protein intact to the immune system . They meet a pivotal role in the body ’ s defense mechanism against foreign invaders , such as pathogens .

• Ancestry and Biochemical Composition: The foundational concept of antibodies can exist ascribe to the pioneering study of Emil von Behring and Kitasato Shibasaburō . Biochemically , antibodies are glycoproteins and fall under the broader class of the immunoglobulin superfamily . While the price “ antibody ” and “ immunoglobulin ” are frequently used synonymously , they essentially concern to the same molecular entity .
• Distribution and Function: Give their office in mediating humoral immunity , antibodies predominantly reside in various torso fluid , include ancestry , secretions , and fluid . Their primary occasion is to recognize and knock off alien antigen , thereby preventing possible infections . The therapeutic potentiality of antibodies is also being explored , with advancements in designing antibodies that can direct intracellular antigens , offering potential strategy for addressing tumor antigens .
• Structural Dimension: Molecularly , antibodies show a discrete Y-shaped configuration . This structure make up four polypeptide chains : two heavy chains and two spark chains . Each chain possesses an NH2 terminal and a C terminal . The NH2 terminal of all four irons , spanning a succession of 100-110 amino acids , organize the Complementarity Determining Region ( CDR ) or the Hypervariable Region ( HVR ) . This region cost essential for antigen recognition . The remaining segment of the molecule is term the framework part or the constant area .
• Classification of Antibody: Base on the variations in the constant area of the heavy chains , immunoglobulins are categorized into five chief class : IgG , IgM , IgA , IgD , and IgE . Each class of immunoglobulin is tailored to combat specific types of antigen , reflecting the evolutionary of the immune system to diverse challenge .

In conclusion , antibody are indispensable components of the immune system , offering a sophisticated line of defense against a myriad of external threats . Their intricate structure and various classifications underline their versatility and specificity in safeguarding the torso against possible infections .

Antibody product

Antibodies , also known as immunoglobulins , are specialized proteins produced and release by plasma B cell . These cell be characterize by mark such as CD-38 , CD-79 , and CD-138 . The initial immunoglobulin produced upon antigen recognition exist IgM .

Role of Antibodies in Adaptive Immunity: Antibody are pivotal in the acquired immune reaction . They facilitate the identification and neutralization of antigen . Each antibody is tailored to make out a specific antigen . The processes mediated by antibodies include :

1. Agglutination and precipitation through the formation of antibody-antigen composite .
2. Priming for phagocytosis , which necessitate macrophages and other immune cell .
3. Block viral receptors .
4. Augmenting other immune answer .
5. Initiating the complement pathway .

B Activation and Pathways: B cell activation is a crucial measure in antibody production . The naive B lymphocytes , upon encounter an antigen , undergo a signal cascade originate at their receptors . These receptors bind to unprocessed , hydrophilic antigen . There are two primary pathways for B lymphocyte activation :

1. Helper T cell-independent pathway: Hither , naive B cell spring up B-cell receptors ( BCRs ) exhibit on their surface . Upon encountering carbohydrate or lipid antigen , these B cells modulation to an fighting land , undergo clonal proliferation , and give rise plasma B cell responsible for synthesize immunoglobulins .
2. Helper T cell-dependent pathway: In this pathway , naive B cells , upon encountering proteinaceous antigen , internalize them through endocytosis . Post-processing , these antigens are presented on the B cell ’ s surface via MHC-II proteins . This presentation facilitate helper T cells ’ recognition , which then secrete interleukins IL-4 and IL-6 . IL-4 activates B cell , while IL-6 advance their proliferation and differentiation .

B Cell Proliferation: B cell proliferation varies based on the activation pathway :

• In the helper T cell-independent pathway , B cell proliferation pass without the need for IL-4 and IL-6 stimulation . This results in the product of plasma B cell but not memory B cell .
• In the helper T cell-dependent pathway , IL-4 and IL-6 are essential for B cell proliferation . This process raise both plasma B cells and memory B cells , which can last up to 10-20 year . Upon re-infection with the same antigen , these memory B cell swiftly excite antibody production .

Antibody-Antigen Interaction: The interaction between an antibody and its specific antigen is termed the antibody-antigen response . This highly specific chemical interaction cost first detailed by Richard J. Goldberg in 1952 , leading some to refer to it as “ Goldberg ’ s theory. ” Following this interaction , an agglutination process can occur , where cross-linking of antigen by antibody effect in a clumping appearance .

Significance of the Antibody-Antigen Response :The antibody-antigen reaction equal cardinal to humoral immunity . By consistently lead up this reaction against alien agents , the torso fortify its immune defense , ensure robust protection against potential menace .

Components of Humoral immunity

Humoral immunity , a vital arm of the adaptive immune system , is mainly mediated by antibody . To in full hold on the intricacies of humoral immune response , it ’ s essential to delve into its key component .

1. Pathogens :Pathogens are harmful microorganism distinct from the torso ’ s normal plant . While many bacteria coexist harmoniously within us , pathogens are alien entity that can cause disease . It ’ s essential to distinguish between these harmful invaders and the benign microorganisms that typically reside in our system .
2. Antigens :Antigens cost specific protein or molecule deliver on the surface of pathogens . They can be proteins , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acids , or lipids . Not every antigen triggers an immune reply . Those that do are term immunogens , with proteins and polysaccharides being the most common . The fighting area of an antigen , responsible for binding to immune cells and antibody receptors , is know as the epitope .
3. Haptens :Haptens are little molecules that , on their own , don ’ t present as all over antigen . However , when combined with bearer protein , they can provoke an immune answer . A classic example exist urushiol from poison ivy , which becomes immunogenic when bound to clamber protein .
4. Lymphoid Organ :These are specialized structure where immune cell train , mature , and get trigger . Primary lymphoid organs , like the red bone center and thymus gland , facilitate the formation and development of lymphocytes . Secondary lymphoid organs , include lymph nodes , spleen , and tonsils , are sites where lymphocytes exist touch off .
5. Antigen-Presenting Cells ( APCs ) :APCs work a pivotal role in the immune response by capture pathogens , processing them , and introduce their antigen on their surface to T cell . This presentation cost crucial for the activation of T cell , bridging innate and adaptive immunity .
6. T Cells :T lymphocytes , or T cells , exist cardinal player in both innate and adaptive immunity . While immediately aim and destroy infected cell , helper T cell act as intermediaries , releasing cytokines to pull B cells and bridge the spread between the two immune systems .
7. B Cell :B cell , or B lymphocytes , function multiple roles . They can do as APCs , secrete cytokines , and most importantly , grow antibodies . Upon activation , B cell can differentiate into plasma cell , which produce antibodies , or memory cell , which allow for long-term immunity against specific pathogens .
8. Antibody :Antibodies , or immunoglobulins , are the main effectors of humoral immunity . They recognize and neutralize pathogens in various fashion , such as direct binding , neutralization , or promoting phagocytosis . There are five main type of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific role in the immune reception .

In decision , humoral immunity is a multifaceted system constitute various components , each bring a unique role in oppose the body against foreign invaders . Understanding these portion and their interactions is crucial for appreciating the complexity and efficiency of our immune system .

Phases/Humoral Immune reception measure

Main Phase/Primary humoral immune response

The humoral immune reply , a pivotal constituent of the adaptive immune system , control in distinct phases to ensure an efficient defense against alien pathogens . The primary stage , also known as the initial response , is characterized by a series of systematic and coordinated events that happen upon the torso ’ s first encounter with an antigen .

1. Antigen Encounter and Processing :Upon the initial impinging with a foreign pathogen , antigen-presenting cell ( APCs ) capture and internalize the antigen . These APCs then digest the antigen , convince specific fragments into major histocompatibility complex course II ( ) surface protein .
2. T Helper Cell Activation :The MHC II surface proteins , now demonstrate the antigen fragment , are recognized by T helper cell . This realization is a crucial measure , as it ensures that the immune system responds specifically to the foreign antigen .
3. Cytokine Production :Upon recognizing the MHC II-antigen composite , T helper cell raise cytokines , signaling particle that play a critical role in regulate the immune response .
4. B Cell Activation and Differentiation :Influenced by the cytokines publish by T helper cell , naïve B cell become activated . Once activated , these B cells undergo differentiation , giving raise to two primary cell types : plasma cell and memory B cell .
5. Antibody Production :The newly formed plasma cells embark on their principal function : the product and secretion of antibody . Initially , IgM antibody are produce . Still , if the pathogen persist still after apex IgM secretion , the immune system may also produce IgG or IgA antibody to bolster the defense .
6. Temporal Dynamics :The main stage live not instantaneous . Stick to the initial exposure to an antigen , there ’ s a lag period , typically ranging from 7 to 10 days , before peak antibody levels are attain in the serum . This lag can depart base on the nature of the antigen ; for example , certain antigen might make a reply within hr , while others might take weeks . Factors determine this period include the antigen ’ sec dosage , its style of rescue ( oral or parenteral ) , and its inherent dimension .
7. Antibody Dynamics :During this chief response , the concentration of antibody in the serum rises for several week before step by step go down . While IgM degree lean to go down more quickly , IgG levels persist for a more lengthy period , extend confirm protection .

In summary , the main phase of the humoral immune reply equal a meticulously orchestrated series of events that ensure the torso mount an in effect defense against new pathogens . This phase lays the foundation for subsequent immune reception , check that the body is better prepared for next encounters with the same antigen .

Secondary Phase/Secondary humoral immune response

The secondary humoral immune reaction , as well referred to as the anamnestic or memory reaction , represents the immune system ’ sec enhanced response to a previously encountered pathogen . This heightened response is facilitated by memory B cells , which equal generated during the primary exposure to the antigen and can hang on for extended length , ranging from weeks to yr .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cells swiftly discern the antigenic determinants of the microorganism . Their previous skirmish with the antigen equips them with a heightened state of readiness , enabling a rapid and efficient response .
2. Clonal Expansion and Differentiation :Upon antigen recognition , memory B cell undergo clonal expansion , give rise a big number of highly-specific plasma cells . These plasma cells are tailored to produce antibody that specifically target the encountered antigen .
3. Enhanced Antibody Production :In the secondary answer , there exist a marked growth in the product of antibodies , surpassing the levels observed during the primary reception by over a thousand-fold . While IgG be the predominant immunoglobulin give rise , there is also a notable production of IgM , IgA , and IgE .
4. Rapid Peak Reaction :One of the trademark of the secondary humoral immune response is the swift attainment of peak antibody floor , typically within a mere 3 to 5 day post-exposure . This contrast with the long lag period watch during the principal response .
5. Persistency of Memory Cells :The enhanced and rapid secondary answer can cost attributed to the presence of antigen-specific memory cells , which prevail post the initial antigen skirmish . These cell undergo extensive proliferation , generate a huge array of specific B cell and plasma cell that mediate the secondary reaction .
6. Qualitative Differences in Antibody Production :While the amount of IgM produced during the secondary reaction live like to that of the main reaction , there is a important growth in the product of IgG . Furthermore , the produced IgG persists for a more extended period during the secondary response .
7. Enhanced Antibody Affinity :Antibodies produced during the secondary response exhibit a high affinity for the antigen , intend they tie more tightly and live less likely to dissociate . This increase binding strength arises from somatic hypermutation , a process where alteration happen in the DNA encoding the antigen-binding site , optimizing antibody-antigen interaction .

Fate of Antigen in Tissues

The lot of an antigen within the torso is largely ascertain by its mode of introduction . This trajectory and eventual localization of the antigen play a pivotal role in shaping the immune response .

1. Subcutaneous Administration :When antigen be bring in subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which drains the interstitial fluid from , captures these antigen and transports them to the lymph nodes . Hither , specialize immune cell can recognize , process , and initiate an immune response against these antigens . Only a minuscule fraction of the antigen achieve the spleen , a secondary lymphoid organ , when introduced via this route .
2. Intravenous Organization :Intravenous rescue of antigens paint a unlike picture . Such antigen are primarily found in systemic organs like the spleen , liver , bone center , kidney , and lungs . The direct debut into the bloodstream allow these antigen to spread widely and interact with various tissues . Interestingly , despite the extensive vascular network associate them , lymph nodes display minimum presence of these intravenously bring in antigen .
3. Antigen Clearance :A substantial component of the antigens , regardless of their route of entry , undergo degradation . Reticuloepithelial cell , which form role of the torso ’ s mononuclear phagocyte system , play a essential role in this process . They engulf and reveal down these antigen , ensure that the torso is not overwhelmed . Post degradation , around three-quarters of these antigen live excreted via the urine , in effect eliminate them from the torso .

Product of Antibodies

The intricate procedure of antibody synthesis is a testament to the body ’ s coordinated defense mechanism . This synthesis live orchestrated through the collaborative efforts of three chief cell type : macrophages , T helper cells , and B cell .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , classified as APCs , are pivotal in presenting antigen to immunocompetent cells . For many T-cell-dependent antigens , including protein and red blood cell , macrophages are essential for work on the antigen before antibody product can begin . Still , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cells show the antigen on their surface , either in its native shape or as processed fragments .
2. Macrophages and Optimal Antigen Photo :Macrophages work a nuanced role in modulating the antigen dose exposed to lymphocytes , see to it the optimum activation of immunological answer . Following macrophage processing , antigen fragments , in conjunction with class II MHC protein , surface on the macrophages . This complex then employ specific receptors on help T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein composite , helper T cell release cytokines . These cytokines , include Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cells to produce antigen-specific antibodies . The B cell , once activated , undergo clonal proliferation , differentiating into plasma cell . These plasma cell cost the factory producing specific immunoglobulins or antibody , which play roles such as knock off toxins and viruses and facilitate pathogen uptake by phagocytic cells .
4. T-cell-independent Antigens :While helper T cell be indispensable for most antibody productions , certain chemical , like polysaccharides , can activate B cell without T cell assistance . These live termed T-cell-independent antigens . However , these antigen prompt B cell to develop only IgM antibodies . The synthesis of early antibody type , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which are exclusively give rise by T help cells .
5. B Cell Antigen Recognition :B cell employ their surface IgM as an antigen receptor , enable them to recognize a plethora of antigens , from proteins to lipids and nucleic acids . This broad recognition spectrum empowers B cells to yield antibodies against a vast array of molecules . However , for protein fragments to be demonstrate to helper T cell , they must equal connect with class II MHC protein .

Theory of antibody formation

The genesis of antibody , essential components of the immune system , has been a subject of scientific wonder and debate . Over time , two primary theory have emerge to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory submit that an immunocompetent cell inherently possesses the capability to give rise a myriad of antibodies . The antigen , upon introduction , instruct these cells to generate specific antibody complementary to itself . Two sub-theories further elucidate this conception :

1. Direct Template Theory:
   • Propose by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , guiding the formation of the antibody . The result antibody particle adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cell , induce a ancestral change . This change require the integration of the antigenic determinant ’ s genocopy into the genome , which is then spend on to progeny cell . However , this explanation hold miss favor over time .

B . Selective Theories

These possibility hint that the torso already possess a repertoire of possible antibodies , and the introduction of an antigen merely take the appropriate 1 . Three sub-theories further detail this conception :

1. Slope Chain Theory:
   • Presented by Ehrlich in 1898 .
   • Argues that immunocompetent cell own turn up receptors that can interact with antigens possessing complementary side chains . Upon antigen introduction , these receptors bind with the antigen , become still . To compensate , the cell overproduces like receptors , which are then relinquish as antibody .
2. Theory:
   • Proposed by Jerne in 1955 .
   • Suggest that during fetal development , the torso produce globulin molecule against all conceivable antigen . Upon antigen introduction , the antigen selectively tie up to the almost complementary globulin molecule , stimulating the product of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduced by Burnet in 1957 .
   • Proposes that during fetal development , a vast array of immunologically competent cell clones , each with a unique antibody design , exist produced . Each of these cell express membrane receptors specific to a special antigen , find out before the cell ’ s photograph to the antigen . Upon antigen introduction , the cell with the correspond receptor cost touch off , proliferates , and produce the corresponding antibody . This theory , widely take over today , put up insights into immunological specificity , memory , and the ability to recognize between self and non-self .

Factors affecting production of antibodies

The production of antibodies , a pivotal aspect of the immune response , is influence by a myriad of factor . Understanding these determinants is crucial for both basic immunology and clinical applications . Herein , we dig into the significant component that modulate antibody product :

1. Genetic Factors:
   • The genetic makeup of an order its response to antigen . Some are responders , give rise antibody upon exposure , while others , termed nonresponders , make not .
   • The immune response ( Ir ) gene , situate on the short arm of chromosome six , governs these version .
2. Age:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , marked by the maturation of lymphoid organs , be achieved by ages 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally regard both humoral and cell-mediated immunity .
   • Specific deficiencies , such as those of amino acid and vitamins , can curtail antibody production .
4. Route of Antigen Administration:
   • The mode of antigen pitch play a pivotal use in arouse an immune response . Parenteral establishment typically cause a more robust reaction equate to oral or nasal path .
5. Dose of Antigen:
   • An optimal dose of antigen be essential for a maximum immune reception . Extremely high or low dosage can lead to immunological paralysis , a state of reduce immune responsiveness .
6. Multiple Antigen:
   • Simultaneous administration of multiple antigens can take to varied antibody answer due to antigenic competition . The exact expression and proportion of these antigen be crucial for accomplish want outcome .
7. Adjuvants:
   • Adjuvants live substances that enhance the immunogenicity of antigen by sustain antigenic stimulus . Examples include Freund ’ s incomplete and complete adjuvants , aluminum salt , and other message like silica particle .
8. Immunosuppressive Agents:
   • These agents moisten the immune answer and are employed in scenarios like transplantation surgeries . Lesson include :
     • X-irradiation: Impedes antibody product place 24 hours of exposure .
     • Radiometric Drugs: Specifically direct B cell , inhibiting their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by regulate interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , restrict cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets disseminate lymphocytes , sparing those in lymphoid organs .

Monoclonal Antibody

Monoclonal antibodies ( mAbs ) are a family of antibody derived from a single cell lineage , ensuring their homogeneity . Unlike polyclonal antibodies , which are produced by multiple plasma cell clones and exist heterologous in nature , monoclonal antibody live specific to a single antigenic determinant .

Source and Distinction: Monoclonal antibody originate from weather like multiple myeloma , where a funny plasma cell clone produces antibody against a specific antigenic determinant . This specificity contrasts with polyclonal antibody , which rise from various plasma cell clones in response to an antigen .

Product Methodology: The pioneering method for monoclonal antibody product was introduced by Kohler and Milstein in 1975 , earn them the Nobel Prize in 1984 . Their technique necessitate the universe of hybridomas , which are form by merge myeloma cells with antibody-producing cells . These hybridomas , once institute , can indefinitely raise monoclonal antibodies , proving priceless for research and diagnostic purposes .

The process involves :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ sec spleen with mouse myeloma cells that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion using agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT media ) that supports hybrid cell increase but inhibits the growing of parent cell .
5. Shield the resulting cell clones for antibody product against the prey antigen .
6. Select and perpetually culturing the clones that produce the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies pose challenge for therapeutic use in humans . Consequently , advancements result to the evolution of human monoclonal antibodies , include chimeric antibody . These chimeric antibody , compose of human constant regions and mouse varying regions , live being explored for leukemia discussion . Furthermore , they can be employed to target tumor cells either by deliver toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Office of Antibody

Antibodies , too know as immunoglobulins , play a pivotal use in the immune system ’ s defense mechanism against pathogens and their associated product . These Y-shaped protein be specifically tailor to make out and neutralize alien invaders , ensuring the host ’ sec protection against various infection . Herein , we dig into the multifaceted function of antibody :

1. Neutralization: One of the primary roles of antibodies be neutralization . By bind at once to pathogens or their toxins , antibody can inhibit their power to bind to and infect horde cell . For instance , antibody specific to bacterial toxins can block the toxin ’ s interaction with horde cells , thereby neutralizing its harmful effect . Similarly , antibodies can prevent viruses or bacteria from initiate infections by hindering their attachment to direct cells .
2. Opsonization: Opsonization is a process where antibody coat pathogens , enhance their recognition and intake by phagocytic cells , such as macrophages and neutrophils . When antibody tie to pathogens , the Fc area of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can also trigger the complement system , a series of proteins that solve in tandem to destroy pathogens . Upon binding to pathogens , sure antibodies can trigger the complement cascade , head to the formation of the membrane approach complex ( MAC ) that instantly lyses certain bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , farther enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological roles , antibodies suffice as essential tools in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can render insights into the individual ’ s humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis are normally employed to evaluate these antibodies , assist in the diagnosis and monitoring of several disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the product of antibodies by B cells in response to alien antigens . This mechanism get be instrumental in defending against several pathogens throughout history . Here , we clear up two discrete example of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox lesions on the ma of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox own catastrophic impacts , particularly decimating indigenous population in the Americas and Australia . However , by the goal of 1979 , a global vaccination campaign successfully eradicated the , notice a monumental accomplishment in the annals of medicine .

The source of vaccination can cost follow back to Edward Jenner ’ s astute observation regarding the resistance of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ s work , variolation , a pattern involve the intentional introduction of pus from smallpox victims into healthy individual , equal apply as a fundamental figure of inoculation . While the underlying mechanisms of the secondary humoral immune response were not so far understood , the rationale of inducing a mild infection to confer future protection exist recognized .

Jenner ’ s groundbreaking experiment involved the inoculation of a young boy with pus descend from cowpox sores of a milkmaid . Unusually , the son exhibit immunity to subsequent smallpox exposure , place the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing weakened or inactivated pathogens , innovative approach were necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine hire a viral vector scheme . Utilizing a genetically modified chimpanzee cold virus , know to elicit robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human body . This alien protein triggers the main humoral reception , culminating in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines deliver the genetic design for the COVID-19 spike protein directly into cells . The cell then synthesize the spike protein , initiate the humoral immune answer . Contrary to some misconceptions , mRNA vaccines do not change human DNA . Instead , they harness the cellular machinery for protein synthesis , bypass the transcription phase and directly initiate translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system be a complex network of cells and proteins that defend the torso against pathogens . It can live broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type have distinct characteristics and functions . Hither , we specify the difference between these two branches of the immune reaction .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies develop	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cells , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ suffer for membranous .	TCR receptors
Accessory receptors involve	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is need	No ( Unprocessed antigens equal discern . )	Yes ( Antigens are first processed and then introduce by MHC of antigen-presenting cell )
Major secretory cells	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( indicate protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells are mainly responsible for producing antibodies in the humoral immune response ?
a ) T cells
b ) Macrophages
c ) B cells
d ) Dendritic cells

Show solution

Which type of immunity is conferred by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

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Which of the following equal NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show solution

The primary immune response cost characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

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Which of the following equal a characteristic of the secondary humoral immune response ?
a ) Slow onset than the main response
b ) Low antibody concentration than the primary response
100 ) Product of memory B cell
d ) Absence of IgG production

Show solution

Which type of cells present antigens to immunocompetent cells ?
a ) T cells
b ) Antigen-presenting cells ( APCs )
c ) Plasma cell
d ) Memory cell

Show response

Which antibody exist chiefly found in mucosal surface and secretion ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit is NOT a characteristic of monoclonal antibody ?
a ) Produced by a single clone of cells
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show answer

The procedure by which antibody enhance the phagocytosis of pathogens is called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the following is the main function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
c ) Facilitate phagocytosis by binding to Fc receptors on phagocytic cell
d ) Induce direct cell lysis

Show reply

FAQ

Address

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Lag Phase: This initial stage ensues directly after the torso equal exposed to an antigen . During this period , the immune system discern and processes the antigen , but no detectable stage of antibodies be present in the bloodstream .
2. Log Phase: Succeed the lag stage , the immune system record the log stage . Hither , there is a consistent and exponential increase in the concentration of antibodies in the bloodstream , indicating active synthesis and release of these molecules by B-lymphocytes and plasma cell .
3. Plateau Phase: As the name indicate , this phase represents a nation of equilibrium . The pace of antibody synthesis is counterbalanced by their catabolism , result to a stabilization in the levels of disseminate antibodies .
4. Phase of Decline: In this last phase , the catabolic activity pass the synthesis of antibodies . This outcome in a gradual reduction in the circulating antibody titers .

Antibodies

Antibodies , much referred to as immunoglobulins ( Ig ) , are specialized protein integral to the immune system . They act a pivotal role in the torso ’ s defense mechanism against foreign invaders , such as pathogens .

• Origin and Biochemical Composition: The foundational concept of antibodies can be attribute to the pioneering study of Emil von Behring and Kitasato Shibasaburō . Biochemically , antibody be glycoproteins and autumn under the broad class of the immunoglobulin superfamily . While the term “ antibody ” and “ immunoglobulin ” cost frequently used synonymously , they fundamentally mention to the same molecular entities .
• Distribution and Purpose: Given their office in mediating humoral immunity , antibodies predominantly reside in respective torso fluids , including blood , secretions , and fluid . Their principal function exist to recognize and neutralize alien antigen , thereby forestall potential infections . The therapeutic potentiality of antibodies is too being search , with advancements in designing antibodies that can target intracellular antigens , offer possible strategy for addressing tumor antigens .
• Structural Dimension: Molecularly , antibodies expose a distinct Y-shaped configuration . This structure comprises four polypeptide chains : two heavy chains and two spark chains . Each chain possesses an NH2 terminal and a C terminal . The NH2 terminal of all four chains , spanning a sequence of 100-110 amino acids , organize the Complementarity Determining Region ( CDR ) or the Hypervariable Region ( HVR ) . This region is essential for antigen realization . The stay on segment of the particle cost term the framework region or the constant region .
• Classification of Antibodies: Base on the variations in the constant region of the heavy chain , immunoglobulins equal categorized into five principal family : IgG , IgM , IgA , IgD , and IgE . Each class of immunoglobulin is tailored to combat specific type of antigen , reflect the evolutionary of the immune system to diverse challenges .

In conclusion , antibodies are indispensable components of the immune system , offering a sophisticated line of defense against a myriad of outside threat . Their intricate structure and various classification underscore their versatility and specificity in safeguarding the torso against possible infections .

Antibody production

Antibodies , too known as immunoglobulins , are specialized protein produced and secreted by plasma B cells . These cell cost characterize by mark such as CD-38 , CD-79 , and CD-138 . The initial immunoglobulin develop upon antigen recognition live IgM .

Role of Antibodies in Adaptive Immunity: Antibody equal pivotal in the take on immune answer . They facilitate the recognition and neutralization of antigen . Each antibody is tailor to recognize a specific antigen . The processes mediated by antibody include :

1. Agglutination and precipitation through the formation of antibody-antigen complex .
2. Priming for phagocytosis , which require macrophages and other immune cell .
3. Blocking viral receptors .
4. Augment other immune answer .
5. Lead up the complement pathway .

B Activation and Pathways: B cell activation is a crucial step in antibody production . The naive B lymphocytes , upon encountering an antigen , undergo a indicate cascade initiated at their receptors . These receptors bind to unprocessed , hydrophilic antigen . There equal two chief pathways for B lymphocyte activation :

1. Helper T cell-independent pathway: Here , naive B cell arise B-cell receptors ( BCRs ) expose on their surface . Upon encounter carbohydrate or lipid antigen , these B cell transition to an active country , undergo clonal proliferation , and produce plasma B cell responsible for synthesizing immunoglobulins .
2. Helper T cell-dependent pathway: In this pathway , naive B cell , upon encounter proteinaceous antigens , internalize them through endocytosis . Post-processing , these antigen equal presented on the B cell ’ s surface via MHC-II proteins . This presentation facilitates helper T cells ’ recognition , which then release interleukins IL-4 and IL-6 . IL-4 activates B cell , while IL-6 promotes their proliferation and differentiation .

B Cell Proliferation: B cell proliferation varies based on the activation pathway :

• In the helper T cell-independent pathway , B cell proliferation occur without the need for IL-4 and IL-6 stimulation . This answer in the production of plasma B cell but not memory B cells .
• In the help T cell-dependent pathway , IL-4 and IL-6 are essential for B cell proliferation . This procedure produce both plasma B cell and memory B cell , which can final up to 10-20 years . Upon re-infection with the same antigen , these memory B cells swiftly stimulate antibody product .

Antibody-Antigen Interaction: The interaction between an antibody and its specific antigen be termed the antibody-antigen response . This highly specific chemical interaction was first detailed by Richard J. Goldberg in 1952 , leading some to cite to it as “ Goldberg ’ s theory. ” Stick to this interaction , an agglutination procedure can pass , where cross-linking of antigen by antibodies solution in a clumping appearance .

Implication of the Antibody-Antigen Reaction :The antibody-antigen response is cardinal to humoral immunity . By consistently initiate this response against foreign agent , the torso strengthen its immune defenses , ensuring robust protection against possible menace .

Components of Humoral immunity

Humoral immunity , a critical branch of the adaptive immune system , is primarily mediated by antibodies . To fully grasp the intricacies of humoral immune answer , it ’ s essential to delve into its key components .

1. Pathogens :Pathogens equal harmful microorganism distinct from the body ’ s normal flora . While many bacteria coexist harmoniously within us , pathogens equal alien entities that can cause disease . It ’ s crucial to differentiate between these harmful invaders and the benign microorganisms that typically occupy in our systems .
2. Antigens :Antigens exist specific proteins or molecules give on the surface of pathogens . They can be proteins , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acid , or lipids . Not every antigen triggers an immune response . Those that serve be termed immunogens , with proteins and polysaccharides being the almost mutual . The active region of an antigen , responsible for tie up to immune cells and antibody receptors , is known as the epitope .
3. Haptens :Haptens be little particle that , on their own , don ’ t present as utter antigen . Still , when compound with carrier proteins , they can arouse an immune response . A classic lesson is urushiol from poison ivy , which becomes immunogenic when boundary to skin proteins .
4. Lymphoid Organs :These equal specialized structures where immune cell arise , mature , and get activate . Primary lymphoid organ , like the red bone center and thymus gland , facilitate the formation and growing of lymphocytes . Secondary lymphoid organs , including lymph nodes , spleen , and tonsils , cost sites where lymphocytes are trigger .
5. Antigen-Presenting Cells ( APCs ) :APCs bring a pivotal role in the immune response by capturing pathogens , work on them , and introduce their antigens on their surface to T cells . This presentation is crucial for the activation of T cell , bridging innate and adaptive immunity .
6. T Cells :T lymphocytes , or T cell , are central players in both innate and adaptive immunity . While at once target and destroy infected cell , helper T cell act as intermediaries , let go cytokines to attract B cell and bridge the spread between the two immune system .
7. B Cells :B cells , or B lymphocytes , service multiple roles . They can work as APCs , secrete cytokines , and most importantly , make antibodies . Upon activation , B cell can distinguish into plasma cell , which produce antibody , or memory cells , which provide long-run immunity against specific pathogens .
8. Antibody :Antibodies , or immunoglobulins , cost the primary effectors of humoral immunity . They discern and knock off pathogens in various manner , such as direct binding , neutralization , or encourage phagocytosis . There live five primary type of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific role in the immune response .

In conclusion , humoral immunity equal a multifaceted system represent respective component , each make for a unique part in oppose the body against alien invaders . Understanding these portion and their interaction cost crucial for appreciate the complexity and efficiency of our immune system .

Phases/Humoral Immune response pace

Primary Phase/Primary humoral immune reaction

The humoral immune response , a pivotal factor of the adaptive immune system , operates in distinct phases to ensure an effective defense against foreign pathogens . The principal stage , also know as the initial reply , is characterize by a series of systematic and coordinated case that occur upon the torso ’ s first skirmish with an antigen .

1. Antigen Encounter and Processing :Upon the initial contact with a alien pathogen , antigen-presenting cells ( APCs ) capture and internalize the antigen . These APCs then stand the antigen , convert specific fragments into major histocompatibility complex class II ( ) surface protein .
2. T Helper Cell Activation :The MHC II surface protein , now presenting the antigen fragments , live recognized by T helper cells . This realization is a essential step , as it ensures that the immune system responds specifically to the foreign antigen .
3. Cytokine Production :Upon make out the MHC II-antigen composite , T helper cells produce cytokines , signal particle that act a vital purpose in regulate the immune reply .
4. B Cell Activation and Differentiation :Influenced by the cytokines issue by T helper cell , naïve B cell become activated . Once activated , these B cells undergo differentiation , have rise to two primary cell type : plasma cells and memory B cell .
5. Antibody Production :The newly formed plasma cells embark on their principal function : the production and secretion of antibodies . Initially , IgM antibody equal produced . Even so , if the pathogen prevail even after crest IgM secretion , the immune system may as well produce IgG or IgA antibody to bolster the defense .
6. Temporal Dynamics :The chief stage equal not instantaneous . Following the initial photograph to an antigen , there ’ s a lag period , typically roam from 7 to 10 days , before peak antibody levels are reached in the serum . This lag can vary based on the nature of the antigen ; for instance , certain antigen might bring on a response within hour , while others might need weeks . Factors influencing this period include the antigen ’ s dosage , its manner of rescue ( oral or parenteral ) , and its underlying dimension .
7. Antibody Dynamics :During this principal reception , the concentration of antibody in the serum stand up for various weeks before gradually declining . While IgM degree tend to go down more rapidly , IgG stage persist for a more lengthy period , offering support security .

In summary , the primary phase of the humoral immune response is a meticulously orchestrated series of events that assure the body climb up an in effect defense against fresh pathogens . This stage lays the foundation for subsequent immune responses , check that the body is good prepared for next encounter with the same antigen .

Secondary Phase/Secondary humoral immune response

The secondary humoral immune response , also referred to as the anamnestic or memory response , make up the immune system ’ sec enhance reaction to a previously run into pathogen . This heightened reception is facilitated by memory B cells , which are generated during the primary exposure to the antigen and can remain for extended length , ranging from weeks to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly recognize the antigenic determinants of the microorganism . Their former encounter with the antigen equips them with a heightened province of readiness , enabling a rapid and effective reply .
2. Clonal Expansion and Differentiation :Upon antigen realization , memory B cell undergo clonal expansion , give rise a big issue of highly-specific plasma cell . These plasma cell live tailored to grow antibodies that specifically direct the encountered antigen .
3. Enhanced Antibody Production :In the secondary response , there is a marked growth in the product of antibody , transcend the stage observe during the primary reply by over a thousand-fold . While IgG exist the paramount immunoglobulin give rise , there exist also a noteworthy product of IgM , IgA , and IgE .
4. Rapid Peak Answer :One of the hallmarks of the secondary humoral immune response is the swift attainment of peak antibody floor , typically within a mere 3 to 5 day post-exposure . This contrasts with the longer lag period watch during the chief response .
5. Persistency of Memory Cells :The enhanced and rapid secondary answer can live attribute to the presence of antigen-specific memory cells , which hang on post the initial antigen skirmish . These cells undergo extensive proliferation , generating a vast array of specific B cells and plasma cells that mediate the secondary response .
6. Qualitative Differences in Antibody Production :While the measure of IgM give rise during the secondary response is similar to that of the main response , there exist a significant increase in the product of IgG . Moreover , the produced IgG persists for a more extensive period during the secondary response .
7. Enhanced Antibody Affinity :Antibodies produced during the secondary response display a higher affinity for the antigen , meaning they tie more tightly and are less likely to dissociate . This increase binding strength arises from somatic hypermutation , a procedure where changes happen in the DNA encoding the antigen-binding site , optimizing antibody-antigen interaction .

Destiny of Antigen in Tissues

The fate of an antigen within the body is largely determined by its mode of introduction . This trajectory and eventual localization of the antigen play a pivotal role in shaping the immune response .

1. Subcutaneous Organization :When antigens live introduced subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which run out the interstitial fluid from , captures these antigen and transports them to the lymph nodes . Here , specialize immune cells can discern , procedure , and originate an immune response against these antigen . Only a minuscule fraction of the antigen arrive at the spleen , a secondary lymphoid organ , when bring in via this route .
2. Intravenous Administration :Intravenous delivery of antigen paint a different photograph . Such antigen are primarily found in systemic organ like the spleen , liver , bone marrow , kidneys , and lungs . The direct entry into the bloodstream grant these antigen to circulate widely and interact with respective tissue . Interestingly , despite the extensive vascular network connecting them , lymph nodes display minimum presence of these intravenously introduced antigens .
3. Antigen Clearance :A significant component of the antigens , regardless of their route of entrance , undergo degradation . Reticuloepithelial cell , which form part of the torso ’ s mononuclear phagocyte system , meet a essential use in this procedure . They engulf and expose down these antigens , ensuring that the torso exist not sweep over . Post degradation , around three-quarters of these antigen exist excreted via the urine , effectively eliminating them from the torso .

Production of Antibody

The intricate process of antibody synthesis is a testament to the body ’ s organize defense mechanism . This synthesis be orchestrated through the collaborative efforts of three primary cell type : macrophages , T helper cell , and B cell .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , classified as APCs , equal pivotal in introduce antigen to immunocompetent cells . For many T-cell-dependent antigens , include proteins and red blood cell , macrophages are essential for work on the antigen before antibody production can commence . However , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cells display the antigen on their surface , either in its native figure or as processed fragment .
2. Macrophages and Optimal Antigen Exposure :Macrophages work a nuanced role in regulate the antigen dose exhibit to lymphocytes , see to it the optimum activation of immunological reception . Comply macrophage processing , antigen fragment , in conjunction with class II MHC proteins , surface on the macrophages . This complex then wage specific receptors on help T cell .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein composite , helper T cell release cytokines . These cytokines , including Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cells to raise antigen-specific antibody . The B cell , once activated , undergo clonal proliferation , differentiate into plasma cell . These plasma cells are the factories producing specific immunoglobulins or antibody , which work use such as neutralize toxins and virus and facilitating pathogen uptake by phagocytic cells .
4. T-cell-independent Antigen :While helper T cell are indispensable for most antibody production , sure chemical , like polysaccharides , can activate B cell without T cell assistance . These are term T-cell-independent antigens . Still , these antigens prompt B cells to produce simply IgM antibody . The synthesis of early antibody type , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which are exclusively raise by T helper cell .
5. B Cell Antigen Recognition :B cells apply their surface IgM as an antigen receptor , enable them to recognize a plethora of antigen , from protein to lipids and nucleic acid . This liberal recognition spectrum empowers B cell to generate antibodies against a huge array of molecules . Even so , for protein fragment to equal presented to helper T cells , they must be associated with class II MHC proteins .

Possibility of antibody formation

The genesis of antibodies , essential constituent of the immune system , has live a topic of scientific wonder and debate . Over time , two main theories have come out to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory posits that an immunocompetent cell inherently possess the capability to produce a myriad of antibodies . The antigen , upon introduction , instructs these cells to yield specific antibody complementary to itself . Two sub-theories further elucidate this concept :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Propose that the antigen or its determinants number as a template , guiding the formation of the antibody . The resulting antibody particle adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduce by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cells , have a ancestral change . This change involves the integration of the antigenic determinant ’ sec genocopy into the genome , which is then passed on to progeny cells . Still , this explanation has lose favor over time .

B . Selective Theories

These theories suggest that the body already possess a repertoire of potential antibodies , and the introduction of an antigen just selects the appropriate one . Three sub-theories further item this concept :

1. Slope Chain Theory:
   • Presented by Ehrlich in 1898 .
   • Argues that immunocompetent cells receive rise receptors that can interact with antigen possess complementary slope irons . Upon antigen introduction , these receptors tie up with the antigen , becoming inactive . To compensate , the cell overproduces like receptors , which are then publish as antibodies .
2. Theory:
   • Proposed by Jerne in 1955 .
   • Suggests that during fetal development , the torso produces globulin molecules against all conceivable antigen . Upon antigen introduction , the antigen selectively bind to the nearly complementary globulin particle , stimulating the production of the corresponding antibody .
3. Clonal Selection Theory:
   • Bring in by Burnet in 1957 .
   • Proposes that during fetal development , a immense array of immunologically competent cell clones , each with a unique antibody practice , exist develop . Each of these cell convey membrane receptors specific to a particular antigen , specify before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the correspond receptor equal activate , proliferates , and give rise the corresponding antibody . This theory , widely consent today , offers insights into immunological specificity , memory , and the ability to recognize between self and non-self .

Factor regard product of antibodies

The product of antibodies , a pivotal scene of the immune reception , live determine by a myriad of element . Understand these determinants is essential for both basic immunology and clinical application . Herein , we delve into the significant component that modulate antibody product :

1. Genetic Component:
   • The genetic makeup of an dictate its answer to antigen . Some are responders , give rise antibodies upon photograph , while others , term nonresponders , cause not .
   • The immune response ( Ir ) gene , settle on the short arm of chromosome six , regulate these version .
2. Age:
   • Neonates and embryos exhibit an underdeveloped immune competence .
   • Full immunological competence , marked by the growing of lymphoid organs , is achieved by ages 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally pretend both humoral and cell-mediated immunity .
   • Specific deficiencies , such as those of amino acid and vitamin , can curtail antibody product .
4. Route of Antigen Administration:
   • The mode of antigen pitch make for a pivotal use in eliciting an immune response . Parenteral administration typically induce a more robust answer equate to oral or nasal path .
5. Dose of Antigen:
   • An optimum dosage of antigen is essential for a maximum immune response . Extremely high or abject dose can lead to immunological paralysis , a state of dilute immune responsiveness .
6. Multiple Antigen:
   • Simultaneous administration of multiple antigen can conduct to varied antibody responses due to antigenic competition . The precise expression and proportion of these antigen be crucial for achieving desire consequence .
7. Adjuvants:
   • Adjuvants exist substance that enhance the immunogenicity of antigen by prolonging antigenic stimulation . Examples include Freund ’ s incomplete and complete adjuvants , aluminum salts , and other substances like silica particles .
8. Immunosuppressive Agents:
   • These agents moisten the immune reception and are employed in scenarios like transplantation surgeries . Examples include :
     • X-irradiation: Impedes antibody production post 24 hr of exposure .
     • Radiometric Drugs: Specifically direct B cells , suppress their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by regulate interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , restrict cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Mark disseminate lymphocytes , sparing those in lymphoid organ .

Monoclonal Antibodies

Monoclonal antibodies ( mAbs ) are a class of antibodies derived from a single cell ancestry , check their homogeneity . Unlike polyclonal antibodies , which are produce by multiple plasma cell clones and are heterologous in nature , monoclonal antibodies are specific to a single antigenic determinant .

Origin and Distinction: Monoclonal antibodies originate from condition like multiple myeloma , where a remarkable plasma cell clone produces antibody against a specific antigenic determinant . This specificity contrasts with polyclonal antibody , which arise from various plasma cell clones in response to an antigen .

Production Methodology: The pioneering method for monoclonal antibody product equal introduce by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique involved the world of hybridomas , which are take form by fusing myeloma cell with antibody-producing cell . These hybridomas , once demonstrate , can indefinitely produce monoclonal antibody , proving priceless for inquiry and diagnostic purposes .

The process require :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ sec spleen with mouse myeloma cells that miss the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion using agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT media ) that supports hybrid cell growth but inhibits the growing of parent cells .
5. Screening the result cell clones for antibody product against the target antigen .
6. Selecting and perpetually culturing the clones that raise the want antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody posed challenges for therapeutic habit in humans . Accordingly , advancements take to the evolution of human monoclonal antibodies , include chimeric antibodies . These chimeric antibody , composed of human constant area and mouse variable regions , be being explored for leukemia discussion . Moreover , they can live employed to direct tumor cells either by present toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Purpose of Antibody

Antibodies , as well know as immunoglobulins , act a pivotal role in the immune system ’ sec defense mechanism against pathogens and their associated product . These Y-shaped proteins live specifically tailored to distinguish and neutralize alien invaders , ensuring the horde ’ s security against various infections . Herein , we delve into the multifaceted functions of antibodies :

1. Neutralization: One of the primary roles of antibody is neutralization . By binding directly to pathogens or their toxins , antibody can conquer their power to seize to and infect host cells . For example , antibody specific to bacterial toxins can block the toxin ’ s interaction with horde cell , thereby neutralize its harmful effects . Likewise , antibodies can prevent virus or bacteria from originate infections by hinder their attachment to direct cells .
2. Opsonization: Opsonization live a procedure where antibodies coat pathogens , enhance their recognition and uptake by phagocytic cell , such as macrophages and neutrophils . When antibody tie up to pathogens , the Fc part of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can as well activate the complement system , a series of protein that work in tandem to destroy pathogens . Upon bind to pathogens , sure antibody can trigger the complement cascade , lead to the formation of the membrane approach composite ( MAC ) that instantly lyses certain bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , farther enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological purpose , antibodies suffice as essential tool in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can furnish insights into the individual ’ sec humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis are ordinarily apply to measure these antibody , aiding in the diagnosis and monitoring of several disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterized by the product of antibodies by B cells in response to alien antigens . This mechanism has make up instrumental in oppose against respective pathogens throughout story . Hither , we elucidate two discrete lesson of humoral immunity , spanning ancient and modern sentence .

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox lesions on the mummy of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impact , especially decimating indigenous populations in the Americas and Australia . Still , by the goal of 1979 , a global vaccination drive successfully eradicated the , marking a massive accomplishment in the annals of medicine .

The origin of vaccination can be traced back to Edward Jenner ’ s sharp observation regarding the resistance of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ sec work , variolation , a pattern involving the intentional introduction of pus from smallpox victims into healthy individuals , was employed as a rudimentary form of inoculation . While the underlie mechanisms of the secondary humoral immune response were not yet understood , the principle of bring on a meek infection to confer next protection be make out .

Jenner ’ s groundbreaking experiment involved the inoculation of a youthful boy with pus derived from cowpox sores of a milkmaid . Remarkably , the boy exhibited immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge pose by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines utilize weaken or inactivated pathogens , innovative approaches live necessitated due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine employ a viral vector scheme . Utilizing a genetically modify chimpanzee cold virus , known to evoke robust immune reaction , the vaccine introduce the SARS-CoV-2 spike protein into the human torso . This foreign protein triggers the primary humoral reply , culminate in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines deliver the genetic design for the COVID-19 spike protein directly into cell . The cell then synthesize the spike protein , initiating the humoral immune response . Contrary to some misconception , mRNA vaccines do not alter human DNA . Rather , they harness the cellular machinery for protein synthesis , bypass the transcription phase and right away initiating translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system equal a complex network of cells and proteins that defends the body against pathogens . It can live broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type have distinct characteristic and functions . Here , we specify the differences between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produce	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors require	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is need	No ( Unprocessed antigen cost recognize . )	Yes ( Antigens exist first processed and then presented by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signal proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cell are chiefly responsible for producing antibody in the humoral immune response ?
a ) T cells
b ) Macrophages
100 ) B cells
d ) Dendritic cells

Show answer

Which type of immunity cost conferred by the production of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

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Which of the pursuit is NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

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The primary immune reception cost characterized by the production of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

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Which of the pursuit is a characteristic of the secondary humoral immune answer ?
a ) Dumb onset than the chief reaction
b ) Lower antibody concentration than the chief response
100 ) Product of memory B cell
d ) Absence of IgG product

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Which type of cell present antigen to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
c ) Plasma cells
d ) Memory cell

Show response

Which antibody cost chiefly get in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show reply

Which of the following equal NOT a characteristic of monoclonal antibody ?
a ) Produced by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic applications

Show reply

The procedure by which antibodies enhance the phagocytosis of pathogens is call :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show result

Which of the pursuit live the main occasion of the Fc area of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by stick to to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA mode : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Antibody product

Antibody , also know as immunoglobulins , are specialized proteins produce and secreted by plasma B cell . These cells exist characterized by markers such as CD-38 , CD-79 , and CD-138 . The initial immunoglobulin produce upon antigen realization be IgM .

Role of Antibodies in Adaptive Immunity: Antibodies are pivotal in the assume immune reaction . They facilitate the recognition and neutralization of antigens . Each antibody equal tailored to discern a specific antigen . The procedure mediated by antibody include :

1. Agglutination and precipitation through the formation of antibody-antigen complex .
2. Priming for phagocytosis , which involves macrophages and other immune cells .
3. Block viral receptors .
4. Augmenting early immune responses .
5. Originate the complement pathway .

B Activation and Pathways: B cell activation exist a essential step in antibody product . The naive B lymphocytes , upon encounter an antigen , undergo a signal cascade lead up at their receptors . These receptors tie up to unprocessed , hydrophilic antigens . There cost two principal pathways for B lymphocyte activation :

1. Helper T cell-independent pathway: Here , naive B cells formulate B-cell receptors ( BCRs ) display on their surface . Upon encounter carbohydrate or lipid antigen , these B cells passage to an fighting nation , undergo clonal proliferation , and produce plasma B cell responsible for synthesizing immunoglobulins .
2. Helper T cell-dependent pathway: In this pathway , naive B cells , upon encounter proteinaceous antigens , internalize them through endocytosis . Post-processing , these antigens are deliver on the B cell ’ s surface via MHC-II protein . This presentation facilitate helper T cells ’ recognition , which then secrete interleukins IL-4 and IL-6 . IL-4 activates B cells , while IL-6 promotes their proliferation and differentiation .

B Cell Proliferation: B cell proliferation varies based on the activation pathway :

• In the helper T cell-independent pathway , B cell proliferation occurs without the need for IL-4 and IL-6 stimulation . This effect in the production of plasma B cells but not memory B cells .
• In the assistant T cell-dependent pathway , IL-4 and IL-6 are essential for B cell proliferation . This process produces both plasma B cells and memory B cells , which can last up to 10-20 yr . Upon re-infection with the same antigen , these memory B cell swiftly stimulate antibody production .

Antibody-Antigen Interaction: The interaction between an antibody and its specific antigen is term the antibody-antigen reaction . This highly specific chemical interaction cost first detailed by Richard J. Goldberg in 1952 , lead some to refer to it as “ Goldberg ’ s theory. ” Follow this interaction , an agglutination process can occur , where cross-linking of antigens by antibody effect in a clumping appearance .

Significance of the Antibody-Antigen Reaction :The antibody-antigen reaction is fundamental to humoral immunity . By consistently initiate this response against foreign agent , the body fortify its immune defenses , ensuring robust protection against potential threats .

Component of Humoral immunity

Humoral immunity , a vital arm of the adaptive immune system , be primarily mediated by antibodies . To fully hold on the intricacies of humoral immune responses , it ’ s essential to dig into its key portion .

1. Pathogens :Pathogens equal harmful microorganisms distinct from the body ’ s normal flora . While many bacteria coexist harmoniously within us , pathogens are foreign entities that can cause disease . It ’ s crucial to distinguish between these harmful invaders and the benign microorganisms that typically reside in our systems .
2. Antigen :Antigen live specific protein or molecule present on the surface of pathogens . They can equal proteins , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acids , or lipids . Not every antigen triggers an immune reception . Those that do are termed immunogens , with proteins and polysaccharides being the almost mutual . The fighting region of an antigen , responsible for tie up to immune cell and antibody receptors , is know as the epitope .
3. Haptens :Haptens be smaller molecules that , on their own , don ’ t present as utter antigen . However , when combined with bearer protein , they can provoke an immune response . A classical example exist urushiol from poison ivy , which become immunogenic when edge to clamber protein .
4. Lymphoid Organ :These are specialized structures where immune cell spring up , mature , and have touch off . Primary lymphoid organs , like the red bone center and thymus gland , facilitate the formation and development of lymphocytes . Secondary lymphoid organs , include lymph nodes , spleen , and tonsils , live sit down where lymphocytes are set off .
5. Antigen-Presenting Cells ( APCs ) :APCs act a pivotal office in the immune reception by capture pathogens , processing them , and introduce their antigens on their surface to T cells . This presentation is crucial for the activation of T cell , bridging innate and adaptive immunity .
6. T Cell :T lymphocytes , or T cell , live cardinal player in both innate and adaptive immunity . While directly target and destroy septic cell , helper T cell number as intermediaries , releasing cytokines to pull B cells and bridging the gap between the two immune systems .
7. B Cell :B cell , or B lymphocytes , serve multiple roles . They can act as APCs , secrete cytokines , and most importantly , give rise antibody . Upon activation , B cells can differentiate into plasma cells , which produce antibodies , or memory cell , which supply long-run immunity against specific pathogens .
8. Antibodies :Antibodies , or immunoglobulins , are the primary effectors of humoral immunity . They recognize and knock off pathogens in various style , such as direct binding , neutralization , or promoting phagocytosis . There live five chief type of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific role in the immune response .

In conclusion , humoral immunity is a multifaceted system comprising respective components , each playing a unique role in oppose the torso against alien invaders . Understanding these component and their interaction is essential for appreciate the complexity and efficiency of our immune system .

Phases/Humoral Immune answer steps

Main Phase/Primary humoral immune response

The humoral immune reaction , a pivotal component of the adaptive immune system , operate in distinct phases to check an effective defense against foreign pathogens . The primary phase , also know as the initial response , exist characterized by a series of systematic and coordinated case that go on upon the torso ’ s first skirmish with an antigen .

1. Antigen Encounter and Processing :Upon the initial contact with a foreign pathogen , antigen-presenting cells ( APCs ) capture and internalize the antigen . These APCs then digest the antigen , convert specific fragments into major histocompatibility complex class II ( ) surface proteins .
2. T Helper Cell Activation :The MHC II surface proteins , today present the antigen fragment , live distinguish by T assistant cells . This realization is a essential step , as it see to it that the immune system answer specifically to the alien antigen .
3. Cytokine Product :Upon recognizing the MHC II-antigen complex , T assistant cell produce cytokines , signal particle that run a critical role in modulating the immune reply .
4. B Cell Activation and Differentiation :Influence by the cytokines released by T assistant cell , naïve B cells become activated . Once activate , these B cells undergo differentiation , giving rise to two primary cell type : plasma cells and memory B cell .
5. Antibody Production :The newly form plasma cell venture on their primary affair : the production and secretion of antibody . Initially , IgM antibodies be produced . However , if the pathogen prevail yet after crest IgM secretion , the immune system may also produce IgG or IgA antibodies to bolster the defense .
6. Temporal Dynamics :The chief phase equal not instantaneous . Following the initial exposure to an antigen , there ’ s a lag period , typically ranging from 7 to 10 day , before peak antibody levels are reached in the serum . This lag can depart based on the nature of the antigen ; for instance , sure antigens might induce a reply within hour , while others might choose weeks . Component determine this period include the antigen ’ s dose , its mode of delivery ( oral or parenteral ) , and its integral dimension .
7. Antibody Dynamics :During this primary response , the concentration of antibody in the serum rises for several weeks before step by step declining . While IgM level run to wane more rapidly , IgG level hang on for a more lengthy period , offering sustained security .

In summary , the primary phase of the humoral immune response is a meticulously orchestrated series of events that ensure the body mounts an in effect defense against new pathogens . This stage put the foundation for subsequent immune responses , see to it that the torso equal better prepared for future skirmish with the same antigen .

Secondary Phase/Secondary humoral immune response

The secondary humoral immune response , also mention to as the anamnestic or memory reaction , represents the immune system ’ s enhance response to a previously encountered pathogen . This heightened response is facilitate by memory B cell , which exist generated during the chief photograph to the antigen and can persist for extensive length , ranging from week to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly make out the antigenic determinants of the microorganism . Their previous encounter with the antigen equips them with a heightened state of readiness , enable a rapid and efficient answer .
2. Clonal Expansion and Differentiation :Upon antigen recognition , memory B cell undergo clonal expansion , producing a large act of highly-specific plasma cells . These plasma cells are tailored to produce antibodies that specifically target the encountered antigen .
3. Enhanced Antibody Production :In the secondary answer , there cost a marked increase in the product of antibodies , surpassing the floor watch during the principal response by over a thousand-fold . While IgG is the paramount immunoglobulin produced , there is also a noteworthy production of IgM , IgA , and IgE .
4. Rapid Peak Reply :One of the trademark of the secondary humoral immune response cost the swift attainment of peak antibody level , typically within a mere 3 to 5 day post-exposure . This contrasts with the longer lag period observed during the principal response .
5. Persistency of Memory Cells :The enhanced and rapid secondary response can be ascribe to the presence of antigen-specific memory cell , which persist post the initial antigen encounter . These cell undergo extensive proliferation , generating a huge array of specific B cells and plasma cells that mediate the secondary response .
6. Qualitative Differences in Antibody Production :While the amount of IgM produce during the secondary response is similar to that of the chief answer , there be a significant growth in the production of IgG . Moreover , the develop IgG persists for a more extended period during the secondary response .
7. Enhanced Antibody Affinity :Antibody produced during the secondary response exhibit a high affinity for the antigen , intend they tie up more tightly and equal less likely to dissociate . This increased binding strength arises from somatic hypermutation , a procedure where change go on in the DNA encoding the antigen-binding site , optimizing antibody-antigen interactions .

Fate of Antigen in Tissues

The fate of an antigen within the body is mostly determined by its manner of introduction . This trajectory and eventual localization of the antigen play a pivotal part in determine the immune reaction .

1. Subcutaneous Administration :When antigens cost introduce subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which run out the interstitial fluid from , catch these antigen and transports them to the lymph nodes . Hither , specialized immune cells can make out , process , and initiate an immune response against these antigens . Solely a minuscule fraction of the antigen reaches the spleen , a secondary lymphoid organ , when introduced via this route .
2. Intravenous Administration :Intravenous delivery of antigen paint a different movie . Such antigen are primarily found in systemic organ like the spleen , liver , bone marrow , kidneys , and lung . The direct debut into the bloodstream allows these antigens to circulate widely and interact with respective tissues . Interestingly , despite the extensive vascular network get in touch them , lymph nodes display minimal presence of these intravenously introduce antigens .
3. Antigen Clearance :A substantial portion of the antigens , no matter of their route of entrance , undergo degradation . Reticuloepithelial cells , which spring part of the body ’ s mononuclear phagocyte system , play a crucial role in this process . They engulf and expose down these antigens , insure that the body is not overwhelmed . Post degradation , around three-quarters of these antigens are excreted via the urine , in effect eliminating them from the body .

Product of Antibodies

The intricate procedure of antibody synthesis live a testament to the body ’ sec coordinate defense mechanism . This synthesis live orchestrated through the collaborative cause of three primary cell types : macrophages , T assistant cell , and B cells .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , classified as APCs , are pivotal in presenting antigen to immunocompetent cells . For many T-cell-dependent antigens , including protein and red blood cell , macrophages equal essential for work on the antigen before antibody product can commence . However , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cells present the antigen on their surface , either in its native sort or as processed fragments .
2. Macrophages and Optimal Antigen Photo :Macrophages run a nuanced role in modulating the antigen dose expose to lymphocytes , ensuring the optimal activation of immunological responses . Following macrophage processing , antigen fragments , in conjunction with category II MHC protein , surface on the macrophages . This complex then employ specific receptors on helper T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein composite , helper T cell release cytokines . These cytokines , include Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cells to produce antigen-specific antibodies . The B cells , once trigger , undergo clonal proliferation , differentiating into plasma cells . These plasma cell are the factories producing specific immunoglobulins or antibody , which play roles such as knock off toxins and virus and facilitating pathogen uptake by phagocytic cell .
4. T-cell-independent Antigen :While helper T cells are indispensable for most antibody production , sure chemicals , like polysaccharides , can touch off B cells without T cell assistance . These exist termed T-cell-independent antigens . Still , these antigen prompt B cells to make alone IgM antibodies . The synthesis of other antibody types , such as IgG , IgA , and IgE , necessitates Interleukins 4 and 5 , which are exclusively produced by T helper cells .
5. B Cell Antigen Recognition :B cells employ their surface IgM as an antigen receptor , enabling them to recognize a plethora of antigens , from proteins to lipids and nucleic acid . This broad realization spectrum empowers B cells to yield antibody against a immense array of molecule . Still , for protein fragment to be presented to helper T cell , they must live associated with grade II MHC protein .

Theories of antibody formation

The genesis of antibodies , essential components of the immune system , get been a subject of scientific curiosity and debate . Over time , two primary theory receive emerged to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory state that an immunocompetent cell inherently possesses the capability to produce a myriad of antibody . The antigen , upon introduction , instruct these cells to yield specific antibody complementary to itself . Two sub-theories further elucidate this concept :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , take the formation of the antibody . The resulting antibody particle adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Bring in by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cell , get a ancestral change . This change call for the integration of the antigenic determinant ’ s genocopy into the genome , which live then passed on to progeny cell . However , this explanation hold lost favor over time .

B . Selective Theories

These theory suggest that the torso already possesses a repertoire of potential antibodies , and the introduction of an antigen just take the appropriate 1 . Three sub-theories further item this conception :

1. Side Chain Theory:
   • Presented by Ehrlich in 1898 .
   • Argues that immunocompetent cells receive surface receptors that can interact with antigen possessing complementary side chain . Upon antigen introduction , these receptors tie up with the antigen , becoming motionless . To make up , the cell overproduces like receptors , which are then release as antibodies .
2. Theory:
   • Suggest by Jerne in 1955 .
   • Propose that during fetal evolution , the body raise globulin molecules against all conceivable antigens . Upon antigen introduction , the antigen selectively binds to the nearly complementary globulin particle , stimulate the production of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduce by Burnet in 1957 .
   • Proposes that during fetal evolution , a vast array of immunologically competent cell clones , each with a unique antibody pattern , exist produced . Each of these cell express membrane receptors specific to a special antigen , determined before the cell ’ s photograph to the antigen . Upon antigen introduction , the cell with the matching receptor exist activated , proliferates , and produces the corresponding antibody . This theory , widely accepted today , offers insight into immunological specificity , memory , and the power to differentiate between self and non-self .

Factors affect product of antibodies

The production of antibody , a pivotal view of the immune response , is determine by a myriad of factor . Understanding these determinants be crucial for both basic immunology and clinical application . Herein , we dig into the significant element that regulate antibody product :

1. Genetic Factors:
   • The genetic makeup of an dictates its answer to antigens . Some equal responders , give rise antibody upon photo , while others , termed nonresponders , cause not .
   • The immune reaction ( Ir ) gene , located on the short branch of chromosome six , governs these variations .
2. Years:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , marked by the growing of lymphoid organ , is attain by age 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally involve both humoral and cell-mediated immunity .
   • Specific deficiencies , such as those of amino acids and vitamin , can curtail antibody production .
4. Path of Antigen Administration:
   • The mode of antigen delivery plays a pivotal role in provoke an immune response . Parenteral administration typically induces a more robust reception compare to oral or nasal path .
5. Dose of Antigen:
   • An optimum dosage of antigen is essential for a maximal immune reply . Extremely high or abject dosage can take to immunological paralysis , a state of reduce immune responsiveness .
6. Multiple Antigens:
   • Simultaneous administration of multiple antigen can lead to varied antibody reception due to antigenic competition . The precise preparation and proportion of these antigens are crucial for achieving desired outcome .
7. Adjuvants:
   • Adjuvants be meaning that enhance the immunogenicity of antigen by sustain antigenic stimulation . Examples include Freund ’ s incomplete and utter adjuvants , aluminum salt , and other meaning like silica particles .
8. Immunosuppressive Agent:
   • These agent moisten the immune response and are utilize in scenarios like transplantation surgeries . Example include :
     • X-irradiation: Impedes antibody product place 24 hours of photograph .
     • Radiometric Drugs: Specifically target B cells , suppress their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtail cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets disseminate lymphocytes , sparing those in lymphoid organ .

Monoclonal Antibody

Monoclonal antibody ( mAbs ) are a grade of antibody derive from a single cell lineage , see to it their homogeneity . Unlike polyclonal antibody , which be develop by multiple plasma cell clones and are heterologous in nature , monoclonal antibody are specific to a single antigenic determinant .

Ancestry and Distinction: Monoclonal antibody develop from circumstance like multiple myeloma , where a singular plasma cell clone produces antibody against a specific antigenic determinant . This specificity contrast with polyclonal antibodies , which arise from several plasma cell clones in reaction to an antigen .

Production Methodology: The pioneering method for monoclonal antibody product cost introduced by Kohler and Milstein in 1975 , make them the Nobel Prize in 1984 . Their technique involved the creation of hybridomas , which are make by mix myeloma cell with antibody-producing cell . These hybridomas , once demonstrate , can indefinitely raise monoclonal antibodies , show invaluable for research and diagnostic intention .

The process involves :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Mix the lymphocytes from the animal ’ s spleen with mouse myeloma cells that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion using agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT medium ) that stand hybrid cell growth but inhibits the growth of parent cells .
5. Screening the resulting cell clones for antibody production against the objective antigen .
6. Choose and perpetually culturing the clones that raise the hope antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies put challenges for therapeutic use in humans . Accordingly , advancements led to the evolution of human monoclonal antibodies , include chimeric antibodies . These chimeric antibody , composed of human constant regions and mouse variable regions , are being explored for leukemia treatment . Furthermore , they can be employed to direct tumor cell either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibody

Antibodies , also known as immunoglobulins , play a pivotal use in the immune system ’ s defense mechanisms against pathogens and their associated products . These Y-shaped proteins live specifically tailored to recognize and neutralize foreign invaders , see to it the horde ’ s security against several infection . Herein , we delve into the multifaceted office of antibody :

1. Neutralization: One of the primary part of antibodies live neutralization . By binding directly to pathogens or their toxins , antibody can inhibit their power to seize to and infect horde cell . For instance , antibody specific to bacterial toxins can obstruct the toxin ’ s interaction with host cells , thereby neutralizing its harmful effect . Similarly , antibodies can prevent viruses or bacteria from initiating infection by hindering their attachment to target cells .
2. Opsonization: Opsonization live a procedure where antibodies coat pathogens , enhancing their recognition and uptake by phagocytic cells , such as macrophages and neutrophils . When antibodies tie up to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can as well spark the complement system , a series of proteins that work in tandem to destroy pathogens . Upon binding to pathogens , certain antibody can trigger the complement cascade , head to the formation of the membrane attack complex ( MAC ) that straight lyses certain bacteria and viruses . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , further enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological part , antibodies serve as crucial tools in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can render insights into the individual ’ s humoral immunity condition . Technique like radial immunodiffusion and immunoelectrophoresis exist commonly employed to measure these antibodies , aiding in the diagnosis and monitoring of respective diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterized by the production of antibodies by B cell in reception to alien antigen . This mechanism get live instrumental in oppose against respective pathogens throughout history . Hither , we clarify two discrete examples of humoral immunity , spanning ancient and modern sentence .

1 . Smallpox and the Advent of Vaccination

Historical record , including the discovery of smallpox wound on the mummy of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impacts , particularly decimating indigenous population in the Americas and Australia . Even so , by the goal of 1979 , a global vaccination campaign successfully eradicated the , mark a massive achievement in the annals of medicine .

The source of vaccination can exist trace back to Edward Jenner ’ s sharp observation regarding the resistance of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ sec work , variolation , a pattern involving the intentional introduction of pus from smallpox victims into sound individuals , was employed as a rudimentary sort of inoculation . While the underlying mechanism of the secondary humoral immune response cost not yet understood , the principle of cause a meek infection to bestow future protection be recognized .

Jenner ’ s groundbreaking experiment involved the inoculation of a young son with pus derive from cowpox sores of a milkmaid . Remarkably , the son expose immunity to subsequent smallpox photograph , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing weaken or inactivated pathogens , innovative approach were necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector scheme . Utilizing a genetically modified chimpanzee cold virus , know to evoke robust immune responses , the vaccine bring in the SARS-CoV-2 spike protein into the human torso . This alien protein activate the primary humoral reaction , culminate in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines rescue the genetic blueprint for the COVID-19 spike protein right away into cells . The cells then synthesize the spike protein , initiating the humoral immune reception . Contrary to some misconception , mRNA vaccines do not alter human DNA . Rather , they harness the cellular machinery for protein synthesis , bypass the transcription stage and instantly originate translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system live a complex network of cells and proteins that defends the torso against pathogens . It can exist broadly categorized into two primary types : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and purpose . Hither , we specify the differences between these two branches of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies produced	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involve	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigens cost realize . )	Yes ( Antigens are first processed and then presented by MHC of antigen-presenting cells )
Major secretory cell	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( indicate protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cell	No	Yes

Quiz

Which cell equal primarily responsible for producing antibody in the humoral immune reaction ?
a ) T cell
b ) Macrophages
c ) B cells
d ) Dendritic cells

Show answer

Which type of immunity is bestow by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show answer

Which of the following cost NOT a affair of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show reply

The primary immune reply is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show solution

Which of the following is a characteristic of the secondary humoral immune response ?
a ) Dumb onset than the chief reaction
b ) Abject antibody concentration than the principal response
c ) Production of memory B cell
d ) Absence of IgG product

Show answer

Which type of cells present antigens to immunocompetent cells ?
a ) T cells
b ) Antigen-presenting cell ( APCs )
c ) Plasma cells
d ) Memory cell

Show answer

Which antibody exist chiefly found in mucosal surface and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the following equal NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cell
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show response

The procedure by which antibodies enhance the phagocytosis of pathogens is scream :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the pursuit cost the primary occasion of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by tie up to Fc receptors on phagocytic cells
d ) Bring on direct cell lysis

Show response

FAQ

Address

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Agglutination and precipitation through the formation of antibody-antigen complex .
2. Priming for phagocytosis , which involves macrophages and early immune cell .
3. Forget viral receptors .
4. Augment early immune responses .
5. Initiating the complement pathway .

B Activation and Pathways: B cell activation live a crucial pace in antibody production . The naive B lymphocytes , upon encounter an antigen , undergo a indicate cascade initiated at their receptors . These receptors tie to unprocessed , hydrophilic antigens . There are two principal pathways for B lymphocyte activation :

1. Helper T cell-independent pathway: Here , naive B cell develop B-cell receptors ( BCRs ) displayed on their surface . Upon encounter carbohydrate or lipid antigen , these B cell modulation to an active country , undergo clonal proliferation , and grow plasma B cells responsible for synthesize immunoglobulins .
2. Helper T cell-dependent pathway: In this pathway , naive B cells , upon encountering proteinaceous antigen , internalize them through endocytosis . Post-processing , these antigens live present on the B cell ’ s surface via MHC-II protein . This demonstration facilitates helper T cell ’ recognition , which then secrete interleukins IL-4 and IL-6 . IL-4 activates B cell , while IL-6 elevate their proliferation and differentiation .

B Cell Proliferation: B cell proliferation varies based on the activation pathway :

• In the helper T cell-independent pathway , B cell proliferation occurs without the need for IL-4 and IL-6 stimulation . This effect in the product of plasma B cell but not memory B cell .
• In the helper T cell-dependent pathway , IL-4 and IL-6 cost essential for B cell proliferation . This process produces both plasma B cells and memory B cell , which can final up to 10-20 years . Upon re-infection with the same antigen , these memory B cell swiftly excite antibody product .

Antibody-Antigen Interaction: The interaction between an antibody and its specific antigen cost term the antibody-antigen reaction . This highly specific chemical interaction equal first detailed by Richard J. Goldberg in 1952 , leading some to relate to it as “ Goldberg ’ s theory. ” Following this interaction , an agglutination process can occur , where cross-linking of antigens by antibody answer in a clumping appearance .

Implication of the Antibody-Antigen Response :The antibody-antigen reaction is cardinal to humoral immunity . By consistently initiating this reaction against foreign agents , the torso fortifies its immune defenses , check robust protection against potential threats .

Component of Humoral immunity

Humoral immunity , a vital arm of the adaptive immune system , exist primarily mediated by antibody . To fully hold on the intricacies of humoral immune responses , it ’ s essential to delve into its key portion .

1. Pathogens :Pathogens are harmful microorganisms distinct from the body ’ s normal flora . While many bacteria coexist harmoniously within us , pathogens are alien entity that can make disease . It ’ s essential to distinguish between these harmful invaders and the benign microorganisms that typically occupy in our systems .
2. Antigen :Antigen cost specific proteins or molecules stage on the surface of pathogens . They can exist proteins , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acid , or lipids . Not every antigen activate an immune reaction . Those that do are termed immunogens , with proteins and polysaccharides exist the most mutual . The fighting area of an antigen , responsible for binding to immune cells and antibody receptors , is known as the epitope .
3. Haptens :Haptens are little particle that , on their own , don ’ t present as all over antigens . However , when combined with carrier proteins , they can evoke an immune response . A classical example is urushiol from poison ivy , which become immunogenic when edge to peel proteins .
4. Lymphoid Organs :These cost specialized structures where immune cells develop , mature , and make activated . Main lymphoid organ , like the red bone marrow and thymus gland , facilitate the formation and growing of lymphocytes . Secondary lymphoid organs , including lymph nodes , spleen , and tonsils , are ride where lymphocytes be activate .
5. Antigen-Presenting Cells ( APCs ) :APCs play a pivotal role in the immune reply by capture pathogens , work on them , and deliver their antigens on their surface to T cells . This presentation is essential for the activation of T cells , bridging innate and adaptive immunity .
6. T Cell :T lymphocytes , or T cells , cost cardinal musician in both innate and adaptive immunity . While immediately target and destroy septic cells , helper T cell act as intermediaries , releasing cytokines to attract B cells and bridge the spread between the two immune system .
7. B Cell :B cells , or B lymphocytes , serve multiple function . They can act as APCs , secrete cytokines , and most importantly , raise antibodies . Upon activation , B cell can differentiate into plasma cell , which grow antibodies , or memory cell , which provide long-run immunity against specific pathogens .
8. Antibody :Antibodies , or immunoglobulins , cost the primary effectors of humoral immunity . They recognize and knock off pathogens in respective ways , such as direct binding , neutralization , or promoting phagocytosis . There live five main types of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific role in the immune response .

In decision , humoral immunity is a multifaceted system comprising respective component , each meet a unique role in defend the torso against foreign invaders . Understand these component and their interaction be crucial for appreciating the complexity and efficiency of our immune system .

Phases/Humoral Immune answer steps

Chief Phase/Primary humoral immune reply

The humoral immune response , a pivotal component of the adaptive immune system , operate in distinct phases to ensure an effective defense against alien pathogens . The primary stage , as well known as the initial response , is characterize by a series of systematic and coordinated events that happen upon the torso ’ s first skirmish with an antigen .

1. Antigen Encounter and Processing :Upon the initial contact with a foreign pathogen , antigen-presenting cell ( APCs ) capture and internalize the antigen . These APCs then endure the antigen , converting specific fragments into major histocompatibility complex course II ( ) surface protein .
2. T Helper Cell Activation :The MHC II surface protein , now present the antigen fragments , equal recognized by T helper cell . This recognition is a essential step , as it ensures that the immune system respond specifically to the foreign antigen .
3. Cytokine Production :Upon recognizing the MHC II-antigen complex , T help cell produce cytokines , signal particle that bring a critical use in modulating the immune response .
4. B Cell Activation and Differentiation :Influenced by the cytokines let go by T helper cells , naïve B cell become activated . Once activate , these B cells undergo differentiation , pay rise to two main cell types : plasma cell and memory B cells .
5. Antibody Production :The newly shape plasma cell embark on their main function : the production and secretion of antibodies . Initially , IgM antibody are produced . Still , if the pathogen remain yet after top IgM secretion , the immune system may also produce IgG or IgA antibody to bolster the defense .
6. Temporal Dynamics :The main stage is not instantaneous . Following the initial photograph to an antigen , there ’ sec a lag period , typically ranging from 7 to 10 days , before peak antibody levels live hand in the serum . This lag can depart based on the nature of the antigen ; for instance , certain antigens might cause a answer within hours , while others might need weeks . Factors influencing this period include the antigen ’ sec dose , its fashion of delivery ( oral or parenteral ) , and its integral dimension .
7. Antibody Dynamics :During this primary reaction , the concentration of antibody in the serum stand up for several week before step by step reject . While IgM point tend to go down more rapidly , IgG levels remain for a more prolonged period , offering sustained protection .

In summary , the primary phase of the humoral immune reception cost a meticulously orchestrated series of events that check the body climb an in effect defense against fresh pathogens . This phase put the foundation for subsequent immune responses , see to it that the body is good prepare for future encounters with the same antigen .

Secondary Phase/Secondary humoral immune reply

The secondary humoral immune reception , also referred to as the anamnestic or memory reception , constitute the immune system ’ sec enhanced response to a previously encounter pathogen . This heightened answer is facilitate by memory B cells , which equal generate during the primary exposure to the antigen and can persist for extended duration , rate from week to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cells swiftly recognize the antigenic determinants of the microorganism . Their former skirmish with the antigen equips them with a heightened state of readiness , enable a rapid and effective answer .
2. Clonal Expansion and Differentiation :Upon antigen recognition , memory B cells undergo clonal expansion , produce a large act of highly-specific plasma cells . These plasma cells are tailor to give rise antibody that specifically direct the encountered antigen .
3. Enhanced Antibody Production :In the secondary answer , there cost a marked growth in the production of antibodies , surpassing the levels observed during the main reaction by over a thousand-fold . While IgG is the paramount immunoglobulin produce , there live also a famous production of IgM , IgA , and IgE .
4. Rapid Peak Response :One of the trademark of the secondary humoral immune response equal the swift attainment of peak antibody stage , typically within a mere 3 to 5 days post-exposure . This contrast with the longer lag period observe during the chief response .
5. Persistence of Memory Cells :The enhanced and rapid secondary response can exist ascribe to the presence of antigen-specific memory cells , which hang on post the initial antigen skirmish . These cells undergo extensive proliferation , generating a vast array of specific B cell and plasma cell that mediate the secondary response .
6. Qualitative Differences in Antibody Production :While the quantity of IgM produced during the secondary response is like to that of the chief response , there is a important growth in the production of IgG . Furthermore , the produced IgG persists for a more lengthy period during the secondary answer .
7. Enhanced Antibody Affinity :Antibody produced during the secondary reception display a high affinity for the antigen , meaning they tie up more tightly and be less likely to divorce . This increased binding force arises from somatic hypermutation , a procedure where changes occur in the DNA encoding the antigen-binding site , optimizing antibody-antigen interactions .

Fate of Antigen in Tissues

The destiny of an antigen within the body be largely determined by its mode of introduction . This trajectory and eventual localization of the antigen act a pivotal office in shaping the immune reaction .

1. Subcutaneous Administration :When antigens live introduce subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which run out the interstitial fluid from , seize these antigen and transport them to the lymph nodes . Hither , specialized immune cells can recognize , procedure , and start an immune response against these antigen . Just a minuscule fraction of the antigen achieve the spleen , a secondary lymphoid organ , when introduced via this route .
2. Intravenous Administration :Intravenous rescue of antigens paint a unlike picture . Such antigen cost primarily see in systemic organs like the spleen , liver , bone marrow , kidney , and lung . The direct entrance into the bloodstream leave these antigens to circle widely and interact with various tissue . Interestingly , despite the extensive vascular network get in touch them , lymph nodes exhibit minimal presence of these intravenously introduced antigen .
3. Antigen Clearance :A significant component of the antigens , regardless of their road of entry , undergo degradation . Reticuloepithelial cells , which spring part of the body ’ s mononuclear phagocyte system , bring a essential part in this process . They engulf and pause down these antigen , insure that the body is not sweep over . Post degradation , around three-quarters of these antigen exist excreted via the urine , in effect get rid of them from the body .

Production of Antibody

The intricate process of antibody synthesis live a testament to the torso ’ sec coordinated defense mechanism . This synthesis is orchestrated through the collaborative feat of three chief cell types : macrophages , T helper cells , and B cell .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , separate as APCs , are pivotal in presenting antigen to immunocompetent cells . For many T-cell-dependent antigens , including proteins and erythrocytes , macrophages are essential for processing the antigen before antibody production can start . Even so , T-cell-independent antigen bypass this macrophage processing . Post-processing , macrophages and dendritic cells exhibit the antigen on their surface , either in its native form or as processed fragments .
2. Macrophages and Optimal Antigen Photo :Macrophages play a nuanced use in regulate the antigen dose exposed to lymphocytes , ensuring the optimal activation of immunological responses . Following macrophage processing , antigen fragment , in conjunction with class II MHC proteins , surface on the macrophages . This complex then engages specific receptors on help T cell .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein complex , helper T cell release cytokines . These cytokines , including Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cell to produce antigen-specific antibodies . The B cell , once activated , undergo clonal proliferation , differentiating into plasma cells . These plasma cells are the factory produce specific immunoglobulins or antibodies , which play part such as neutralizing toxins and virus and facilitating pathogen uptake by phagocytic cells .
4. T-cell-independent Antigens :While helper T cell are indispensable for most antibody productions , certain chemicals , like polysaccharides , can touch off B cell without T cell assistance . These be term T-cell-independent antigens . However , these antigen prompt B cell to give rise only IgM antibody . The synthesis of other antibody types , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which live exclusively develop by T assistant cell .
5. B Cell Antigen Recognition :B cell employ their surface IgM as an antigen receptor , enable them to distinguish a plethora of antigen , from proteins to lipids and nucleic acids . This liberal realization spectrum empowers B cell to generate antibody against a vast array of molecules . Even so , for protein fragment to be presented to helper T cells , they must be connect with family II MHC proteins .

Theories of antibody formation

The genesis of antibody , essential components of the immune system , hold live a subject of scientific curiosity and debate . Over time , two chief theory have issue to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory submit that an immunocompetent cell inherently possess the capacity to give rise a myriad of antibody . The antigen , upon introduction , instruct these cells to yield specific antibodies complementary to itself . Two sub-theories further elucidate this concept :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , point the formation of the antibody . The result antibody particle follow a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon go into antibody-producing cells , have a ancestral change . This change demand the integration of the antigenic determinant ’ sec genocopy into the genome , which cost then occur on to progeny cells . However , this explanation have miss favor over time .

B . Selective Theory

These theory suggest that the body already possesses a repertoire of potential antibody , and the introduction of an antigen simply select the appropriate one . Three sub-theories further detail this conception :

1. Slope Chain Theory:
   • Introduce by Ehrlich in 1898 .
   • Argues that immunocompetent cells have turn up receptors that can interact with antigen possessing complementary slope chains . Upon antigen introduction , these receptors tie up with the antigen , becoming motionless . To compensate , the cell overproduces like receptors , which exist then released as antibodies .
2. Theory:
   • Advise by Jerne in 1955 .
   • Suggests that during fetal evolution , the torso produce globulin particle against all conceivable antigens . Upon antigen introduction , the antigen selectively binds to the almost complementary globulin particle , stimulating the production of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduced by Burnet in 1957 .
   • Proposes that during fetal development , a immense array of immunologically competent cell clones , each with a unique antibody pattern , be develop . Each of these cell express membrane receptors specific to a particular antigen , determined before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the couple receptor is activated , proliferates , and produce the corresponding antibody . This theory , widely accepted today , offer insights into immunological specificity , memory , and the power to differentiate between self and non-self .

Factors regard production of antibodies

The product of antibody , a pivotal view of the immune response , is influence by a myriad of factors . Understanding these determinants is crucial for both basic immunology and clinical application . Herein , we dig into the important factors that regulate antibody production :

1. Genetic Factors:
   • The genetic makeup of an prescribe its response to antigen . Some cost responders , develop antibody upon exposure , while others , termed nonresponders , do not .
   • The immune reply ( Ir ) gene , located on the short sleeve of chromosome six , regulate these variation .
2. Years:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , marked by the maturation of lymphoid organ , is reach by years 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally strike both humoral and cell-mediated immunity .
   • Specific deficiencies , such as those of amino acids and vitamins , can restrict antibody production .
4. Path of Antigen Administration:
   • The manner of antigen delivery plays a pivotal role in arouse an immune reply . Parenteral administration typically induce a more robust response equate to oral or nasal routes .
5. Dose of Antigen:
   • An optimum dose of antigen is essential for a maximal immune response . Extremely high or low dose can head to immunological paralysis , a province of reduced immune responsiveness .
6. Multiple Antigens:
   • Concurrent administration of multiple antigens can result to varied antibody reception due to antigenic competitor . The exact formulation and proportion of these antigens equal crucial for achieving desire outcome .
7. Adjuvants:
   • Adjuvants cost substances that enhance the immunogenicity of antigens by sustain antigenic stimulus . Examples include Freund ’ s incomplete and utter adjuvants , aluminum salts , and other substances like silica particles .
8. Immunosuppressive Agent:
   • These agents moisten the immune response and are employed in scenarios like transplantation surgeries . Lesson include :
     • X-irradiation: Impedes antibody product place 24 hours of exposure .
     • Radiometric Drugs: Specifically direct B cells , inhibit their replication .
     • Corticosteroids: Lessen the reactivity of B and T lymphocytes by regulate interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtail cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets circulating lymphocytes , spare those in lymphoid organ .

Monoclonal Antibodies

Monoclonal antibody ( mAbs ) are a class of antibody descend from a single cell ancestry , check their homogeneity . Unlike polyclonal antibody , which cost give rise by multiple plasma cell clones and exist heterologous in nature , monoclonal antibodies cost specific to a single antigenic determinant .

Origin and Distinction: Monoclonal antibodies originate from conditions like multiple myeloma , where a curious plasma cell clone produces antibodies against a specific antigenic determinant . This specificity contrast with polyclonal antibodies , which arise from various plasma cell clones in response to an antigen .

Production Methodology: The pioneering method for monoclonal antibody product equal introduce by Kohler and Milstein in 1975 , bring in them the Nobel Prize in 1984 . Their technique call for the world of hybridomas , which are formed by fuse myeloma cells with antibody-producing cell . These hybridomas , once establish , can indefinitely raise monoclonal antibodies , prove priceless for inquiry and diagnostic purposes .

The procedure involves :

1. Inoculating an beast , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ sec spleen with mouse myeloma cells that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion using agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT media ) that affirm hybrid cell growth but inhibits the growth of parent cells .
5. Shield the result cell clones for antibody product against the target antigen .
6. Selecting and perpetually culturing the clones that produce the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies set challenges for therapeutic use in man . Consequently , advancements run to the development of human monoclonal antibody , including chimeric antibody . These chimeric antibody , compile of human constant regions and mouse varying region , are be explored for leukemia discussion . Moreover , they can be employed to direct tumor cells either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibody

Antibodies , too known as immunoglobulins , act a pivotal use in the immune system ’ s defense mechanism against pathogens and their associated products . These Y-shaped protein exist specifically tailored to recognize and knock off alien invaders , ensuring the horde ’ sec protection against several infection . Herein , we delve into the multifaceted office of antibodies :

1. Neutralization: One of the primary role of antibody equal neutralization . By binding directly to pathogens or their toxins , antibodies can inhibit their ability to seize to and infect horde cells . For example , antibody specific to bacterial toxins can block the toxin ’ s interaction with horde cell , thereby knock off its harmful effect . Similarly , antibody can keep virus or bacteria from initiating infection by hindering their attachment to direct cells .
2. Opsonization: Opsonization be a procedure where antibody coat pathogens , enhance their recognition and uptake by phagocytic cell , such as macrophages and neutrophil . When antibodies tie to pathogens , the Fc area of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can also activate the complement system , a series of proteins that work in tandem to ruin pathogens . Upon binding to pathogens , sure antibody can trigger the complement cascade , lead to the formation of the membrane attack complex ( MAC ) that directly lyses sure bacteria and viruses . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , farther enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological part , antibody service as essential tool in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can supply insights into the individual ’ sec humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis are commonly utilize to assess these antibody , assist in the diagnosis and monitoring of several diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , cost characterize by the product of antibody by B cells in response to alien antigen . This mechanism make live instrumental in oppose against various pathogens throughout story . Here , we illuminate two distinct examples of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical record , including the discovery of smallpox lesions on the mama of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox hold catastrophic impact , in particular decimating indigenous population in the Americas and Australia . Even so , by the end of 1979 , a global vaccination movement successfully eradicated the , mark a massive achievement in the annals of medicine .

The origins of vaccination can be retrace back to Edward Jenner ’ s sharp observation regarding the resistance of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ sec work , variolation , a practice require the intentional introduction of pus from smallpox victim into healthy individuals , live employed as a fundamental figure of inoculation . While the underlie mechanisms of the secondary humoral immune reaction exist not so far understood , the principle of inducing a meek infection to bestow future security was distinguish .

Jenner ’ s groundbreaking experiment necessitate the inoculation of a youthful boy with pus derived from cowpox sores of a milkmaid . Unusually , the son exhibited immunity to subsequent smallpox photograph , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge put by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing weaken or inactivated pathogens , innovative approach were necessitated due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employ a viral vector scheme . Utilizing a genetically modified chimpanzee cold virus , known to provoke robust immune responses , the vaccine bring in the SARS-CoV-2 spike protein into the human body . This foreign protein triggers the primary humoral reply , culminate in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines have the genetic design for the COVID-19 spike protein at once into cell . The cell then synthesize the spike protein , originate the humoral immune response . Contrary to some misconceptions , mRNA vaccines serve not change human DNA . Rather , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and directly initiate translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system is a complex network of cell and protein that defend the body against pathogens . It can be broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type has distinct characteristics and affair . Here , we delineate the differences between these two branches of the immune answer .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies raise	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cell , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is require	No ( Unprocessed antigens live recognized . )	Yes ( Antigen are first work on and then presented by MHC of antigen-presenting cell )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signal protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cells	No	Yes

Quiz

Which cell are chiefly responsible for develop antibody in the humoral immune reception ?
a ) T cell
b ) Macrophages
c ) B cell
d ) Dendritic cells

Show answer

Which type of immunity is conferred by the production of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show answer

Which of the following is NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show reply

The main immune reaction is characterized by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the following live a characteristic of the secondary humoral immune reply ?
a ) Slow onset than the principal reply
b ) Lower antibody concentration than the chief reception
c ) Production of memory B cell
d ) Absence of IgG product

Show answer

Which type of cell present antigen to immunocompetent cell ?
a ) T cells
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cells
d ) Memory cells

Show answer

Which antibody exist primarily find in mucosal surface and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show solution

Which of the following exist NOT a characteristic of monoclonal antibody ?
a ) Produce by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Expend in diagnostic and therapeutic application

Show answer

The process by which antibody enhance the phagocytosis of pathogens exist call :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the pursuit is the primary purpose of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by bind to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show reply

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA mode : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Helper T cell-independent pathway: Here , naive B cell formulate B-cell receptors ( BCRs ) exhibit on their surface . Upon encounter carbohydrate or lipid antigen , these B cells modulation to an fighting province , undergo clonal proliferation , and grow plasma B cells responsible for synthesizing immunoglobulins .
2. Helper T cell-dependent pathway: In this pathway , naive B cell , upon encountering proteinaceous antigens , internalize them through endocytosis . Post-processing , these antigens are confront on the B cell ’ s surface via MHC-II protein . This presentation facilitate helper T cell ’ realization , which then secrete interleukins IL-4 and IL-6 . IL-4 activates B cells , while IL-6 elevate their proliferation and differentiation .

B Cell Proliferation: B cell proliferation varies based on the activation pathway :

• In the help T cell-independent pathway , B cell proliferation go on without the need for IL-4 and IL-6 stimulation . This results in the production of plasma B cell but not memory B cell .
• In the helper T cell-dependent pathway , IL-4 and IL-6 live essential for B cell proliferation . This procedure develop both plasma B cells and memory B cells , which can final up to 10-20 years . Upon re-infection with the same antigen , these memory B cells swiftly stimulate antibody product .

Antibody-Antigen Interaction: The interaction between an antibody and its specific antigen is term the antibody-antigen reaction . This highly specific chemical interaction was first detailed by Richard J. Goldberg in 1952 , leading some to refer to it as “ Goldberg ’ s theory. ” Follow this interaction , an agglutination procedure can happen , where cross-linking of antigen by antibodies outcome in a clumping appearance .

Implication of the Antibody-Antigen Reaction :The antibody-antigen reaction is cardinal to humoral immunity . By consistently lead up this response against foreign agent , the body fortify its immune defense , ensuring robust security against potential threats .

Constituent of Humoral immunity

Humoral immunity , a vital arm of the adaptive immune system , is primarily mediated by antibodies . To in full hold on the intricacies of humoral immune responses , it ’ s essential to delve into its key portion .

1. Pathogens :Pathogens are harmful microorganism distinct from the torso ’ s normal flora . While many bacteria coexist harmoniously within us , pathogens equal alien entity that can cause disease . It ’ s crucial to differentiate between these harmful invaders and the benign microorganisms that typically reside in our system .
2. Antigens :Antigens live specific protein or molecules show on the surface of pathogens . They can exist proteins , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acid , or lipids . Not every antigen triggers an immune answer . Those that make be term immunogens , with proteins and polysaccharides cost the almost mutual . The active part of an antigen , responsible for binding to immune cell and antibody receptors , is know as the epitope .
3. Haptens :Haptens are smaller molecules that , on their own , don ’ t present as complete antigens . Even so , when combined with bearer proteins , they can elicit an immune answer . A classical model is urushiol from poison ivy , which becomes immunogenic when limit to skin proteins .
4. Lymphoid Organs :These live specialized structures where immune cells develop , mature , and get activated . Primary lymphoid organ , like the red bone marrow and thymus gland , facilitate the formation and maturation of lymphocytes . Secondary lymphoid organs , include lymph nodes , spleen , and tonsils , exist sites where lymphocytes are activated .
5. Antigen-Presenting Cells ( APCs ) :APCs meet a pivotal role in the immune response by capture pathogens , processing them , and presenting their antigen on their surface to T cells . This demonstration is crucial for the activation of T cell , bridge innate and adaptive immunity .
6. T Cells :T lymphocytes , or T cell , cost central player in both innate and adaptive immunity . While directly prey and destroy infected cell , helper T cell number as intermediaries , releasing cytokines to attract B cell and bridging the gap between the two immune systems .
7. B Cells :B cells , or B lymphocytes , do multiple use . They can act as APCs , secrete cytokines , and most importantly , give rise antibody . Upon activation , B cells can distinguish into plasma cells , which produce antibody , or memory cell , which provide long-term immunity against specific pathogens .
8. Antibody :Antibodies , or immunoglobulins , be the main effectors of humoral immunity . They make out and knock off pathogens in respective ways , such as direct binding , neutralization , or encourage phagocytosis . There cost five main types of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific role in the immune answer .

In conclusion , humoral immunity live a multifaceted system contain several constituent , each playing a unique purpose in defending the torso against alien invaders . Understand these portion and their interactions live essential for appreciating the complexity and efficiency of our immune system .

Phases/Humoral Immune response stairs

Primary Phase/Primary humoral immune response

The humoral immune response , a pivotal factor of the adaptive immune system , operates in distinct stage to ensure an in effect defense against foreign pathogens . The chief phase , too know as the initial reception , is characterized by a series of systematic and coordinated event that go on upon the body ’ s first encounter with an antigen .

1. Antigen Encounter and Processing :Upon the initial contact with a alien pathogen , antigen-presenting cells ( APCs ) capture and internalize the antigen . These APCs then tolerate the antigen , convince specific fragments into major histocompatibility complex course II ( ) surface proteins .
2. T Helper Cell Activation :The MHC II surface proteins , now presenting the antigen fragments , are recognized by T helper cells . This realization cost a crucial measure , as it check that the immune system responds specifically to the alien antigen .
3. Cytokine Production :Upon distinguish the MHC II-antigen composite , T helper cells give rise cytokines , signal molecules that play a vital role in modulating the immune response .
4. B Cell Activation and Differentiation :Influenced by the cytokines released by T helper cell , naïve B cells become activated . Once activated , these B cell undergo differentiation , giving raise to two chief cell type : plasma cells and memory B cell .
5. Antibody Production :The newly formed plasma cell venture on their chief function : the production and secretion of antibodies . Initially , IgM antibodies are produced . However , if the pathogen persist even after peak IgM secretion , the immune system may as well produce IgG or IgA antibodies to bolster the defense .
6. Temporal Dynamics :The principal phase is not instantaneous . Following the initial exposure to an antigen , there ’ sec a lag period , typically rate from 7 to 10 days , before peak antibody levels are reached in the serum . This lag can vary based on the nature of the antigen ; for instance , sure antigens might induce a response within hr , while others might remove weeks . Factor influencing this period include the antigen ’ s dose , its style of delivery ( oral or parenteral ) , and its integral properties .
7. Antibody Dynamics :During this primary reaction , the concentration of antibody in the serum develop for various weeks before gradually declining . While IgM levels tend to wane more rapidly , IgG degree persist for a more extended period , extend sustained security .

In summary , the primary phase of the humoral immune reception is a meticulously orchestrated series of effect that assure the body climb up an in effect defense against fresh pathogens . This phase put the foundation for subsequent immune responses , assure that the body live good develop for next skirmish with the same antigen .

Secondary Phase/Secondary humoral immune response

The secondary humoral immune reaction , too refer to as the anamnestic or memory reply , symbolize the immune system ’ s enhance response to a previously encountered pathogen . This heightened reply be facilitate by memory B cells , which live generated during the primary exposure to the antigen and can persist for extended durations , place from weeks to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly recognize the antigenic determinants of the microorganism . Their former encounter with the antigen equips them with a heightened state of readiness , enabling a rapid and effective answer .
2. Clonal Expansion and Differentiation :Upon antigen realization , memory B cell undergo clonal expansion , give rise a large number of highly-specific plasma cells . These plasma cell exist tailor to produce antibodies that specifically target the encountered antigen .
3. Enhanced Antibody Production :In the secondary answer , there is a marked increase in the product of antibodies , transcend the degree observe during the primary response by over a thousand-fold . While IgG live the paramount immunoglobulin develop , there is also a famous production of IgM , IgA , and IgE .
4. Rapid Peak Reply :One of the hallmarks of the secondary humoral immune reception is the swift attainment of crest antibody levels , typically within a mere 3 to 5 day post-exposure . This contrast with the long lag period notice during the primary answer .
5. Persistency of Memory Cells :The enhanced and rapid secondary response can be attribute to the presence of antigen-specific memory cell , which persist post the initial antigen encounter . These cell undergo extensive proliferation , generating a immense array of specific B cell and plasma cells that mediate the secondary answer .
6. Qualitative Difference in Antibody Product :While the measure of IgM give rise during the secondary reception equal like to that of the primary response , there equal a important increase in the production of IgG . Furthermore , the produced IgG persists for a more prolonged period during the secondary reaction .
7. Enhanced Antibody Affinity :Antibodies produced during the secondary response exhibit a high affinity for the antigen , meaning they tie more tightly and are less probable to divorce . This increase binding force arises from somatic hypermutation , a process where changes go on in the DNA encoding the antigen-binding site , optimizing antibody-antigen interactions .

Fate of Antigen in Tissues

The fate of an antigen within the body is mostly determined by its manner of introduction . This trajectory and eventual localization of the antigen work a pivotal purpose in shaping the immune response .

1. Subcutaneous Administration :When antigens cost introduced subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which drains the interstitial fluid from , capture these antigen and transports them to the lymph nodes . Here , specialize immune cell can recognize , procedure , and start an immune response against these antigens . Simply a minuscule fraction of the antigen reaches the spleen , a secondary lymphoid organ , when introduced via this route .
2. Intravenous Administration :Intravenous delivery of antigen paint a different picture . Such antigens are primarily find in systemic organ like the spleen , liver , bone marrow , kidneys , and lungs . The direct entry into the bloodstream allows these antigen to circulate widely and interact with respective tissue . Interestingly , despite the extensive vascular network get in touch them , lymph nodes exhibit minimal presence of these intravenously bring in antigens .
3. Antigen Clearance :A significant luck of the antigens , regardless of their road of debut , undergo degradation . Reticuloepithelial cells , which make portion of the body ’ s mononuclear phagocyte system , meet a essential use in this process . They engulf and break down these antigen , ensuring that the torso is not overwhelmed . Post degradation , around three-quarters of these antigen are excreted via the urine , effectively eliminating them from the body .

Production of Antibodies

The intricate procedure of antibody synthesis is a testament to the torso ’ sec coordinate defense mechanism . This synthesis is orchestrated through the collaborative efforts of three primary cell types : macrophages , T helper cells , and B cell .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cell , classify as APCs , exist pivotal in presenting antigens to immunocompetent cells . For many T-cell-dependent antigen , include protein and erythrocytes , macrophages equal essential for processing the antigen before antibody product can embark on . Even so , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cell show the antigen on their surface , either in its native form or as processed fragments .
2. Macrophages and Optimal Antigen Exposure :Macrophages bring a nuanced use in regulate the antigen dosage exposed to lymphocytes , ensuring the optimum activation of immunological answer . Following macrophage processing , antigen fragments , in conjunction with category II MHC proteins , surface on the macrophages . This complex then employ specific receptors on help T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein composite , helper T cells release cytokines . These cytokines , include Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cell to produce antigen-specific antibody . The B cell , once activated , undergo clonal proliferation , differentiating into plasma cells . These plasma cell live the factories producing specific immunoglobulins or antibody , which play roles such as knock off toxins and virus and facilitate pathogen uptake by phagocytic cells .
4. T-cell-independent Antigens :While helper T cells be indispensable for most antibody productions , sure chemical , like polysaccharides , can activate B cells without T cell assistance . These are term T-cell-independent antigen . However , these antigen prompt B cells to make just IgM antibodies . The synthesis of other antibody type , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which are exclusively develop by T helper cells .
5. B Cell Antigen Recognition :B cells hire their surface IgM as an antigen receptor , enabling them to realize a plethora of antigen , from proteins to lipids and nucleic acid . This broad recognition spectrum empowers B cell to generate antibody against a vast array of particle . However , for protein fragments to be presented to helper T cell , they must be associated with grade II MHC protein .

Theories of antibody formation

The genesis of antibody , essential components of the immune system , hold make up a study of scientific wonder and debate . Over time , two primary theories receive emerged to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory state that an immunocompetent cell inherently possess the capability to make a myriad of antibodies . The antigen , upon introduction , instructs these cell to yield specific antibodies complementary to itself . Two sub-theories further elucidate this conception :

1. Direct Template Theory:
   • Propose by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , guiding the formation of the antibody . The result antibody particle adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cells , cause a hereditary change . This change demand the integration of the antigenic determinant ’ sec genocopy into the genome , which equal then occur on to progeny cells . Even so , this explanation have miss favor over time .

B . Selective Possibility

These possibility suggest that the body already possesses a repertoire of possible antibodies , and the introduction of an antigen merely choose the appropriate one . Three sub-theories further point this conception :

1. Slope Chain Theory:
   • Deliver by Ehrlich in 1898 .
   • Argues that immunocompetent cells hold rise receptors that can interact with antigen possess complementary side chains . Upon antigen introduction , these receptors tie with the antigen , becoming motionless . To compensate , the cell overproduces like receptors , which live then released as antibodies .
2. Theory:
   • Suggest by Jerne in 1955 .
   • Suggest that during fetal development , the body raise globulin molecules against all conceivable antigen . Upon antigen introduction , the antigen selectively binds to the nearly complementary globulin molecule , stimulate the product of the corresponding antibody .
3. Clonal Selection Theory:
   • Bring in by Burnet in 1957 .
   • Proposes that during fetal evolution , a immense array of immunologically competent cell clones , each with a unique antibody convention , is produced . Each of these cell express membrane receptors specific to a particular antigen , determined before the cell ’ s photo to the antigen . Upon antigen introduction , the cell with the cope with receptor is trigger , proliferates , and produces the corresponding antibody . This theory , widely accepted today , offer insight into immunological specificity , memory , and the power to distinguish between self and non-self .

Element affecting production of antibodies

The production of antibody , a pivotal aspect of the immune reception , is influence by a myriad of factors . Understanding these determinants be crucial for both basic immunology and clinical application . Herein , we dig into the significant factors that modulate antibody production :

1. Genetic Component:
   • The genetic makeup of an prescribe its response to antigens . Some equal responders , producing antibody upon exposure , while others , termed nonresponders , make not .
   • The immune response ( Ir ) gene , located on the short arm of chromosome six , governs these variation .
2. Age:
   • Neonates and embryos exhibit an underdeveloped immune competence .
   • Full immunological competence , marked by the growing of lymphoid organ , is achieve by years 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acids and vitamin , can curtail antibody production .
4. Route of Antigen Administration:
   • The mode of antigen delivery plays a pivotal office in provoke an immune response . Parenteral establishment typically cause a more robust response compared to oral or nasal routes .
5. Dose of Antigen:
   • An optimum dose of antigen is essential for a maximum immune response . Extremely high or low doses can conduct to immunological paralysis , a country of reduce immune responsiveness .
6. Multiple Antigens:
   • Simultaneous administration of multiple antigens can take to varied antibody responses due to antigenic competition . The precise expression and proportion of these antigens are essential for achieving desired outcomes .
7. Adjuvants:
   • Adjuvants are substance that enhance the immunogenicity of antigens by sustain antigenic stimulus . Examples include Freund ’ s incomplete and all over adjuvants , aluminum salts , and other substance like silica particles .
8. Immunosuppressive Agent:
   • These agent moisten the immune reply and are utilize in scenarios like transplantation surgeries . Examples include :
     • X-irradiation: Impedes antibody production place 24 hour of photograph .
     • Radiometric Drugs: Specifically target B cells , suppress their replication .
     • Corticosteroids: Decrease the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Target circulating lymphocytes , sparing those in lymphoid organs .

Monoclonal Antibodies

Monoclonal antibodies ( mAbs ) are a family of antibodies deduce from a single cell lineage , check their homogeneity . Unlike polyclonal antibody , which equal produce by multiple plasma cell clones and cost heterologous in nature , monoclonal antibodies live specific to a single antigenic determinant .

Origin and Distinction: Monoclonal antibodies originate from conditions like multiple myeloma , where a singular plasma cell clone give rise antibody against a specific antigenic determinant . This specificity contrasts with polyclonal antibody , which arise from various plasma cell clones in reply to an antigen .

Product Methodology: The pioneering method for monoclonal antibody product live introduced by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique involved the creation of hybridomas , which be formed by fuse myeloma cell with antibody-producing cell . These hybridomas , once lay down , can indefinitely produce monoclonal antibodies , proving priceless for inquiry and diagnostic purposes .

The procedure involve :

1. Inoculating an creature , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ sec spleen with mouse myeloma cell that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion expend agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT medium ) that supports hybrid cell growing but conquer the growing of parent cells .
5. Screening the resulting cell clones for antibody product against the object antigen .
6. Selecting and perpetually culturing the clones that give rise the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies posed challenge for therapeutic use in man . Accordingly , advancements led to the evolution of human monoclonal antibodies , include chimeric antibodies . These chimeric antibodies , composed of human constant regions and mouse varying regions , are being search for leukemia discussion . Moreover , they can be employed to target tumor cells either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibody

Antibody , also known as immunoglobulins , run a pivotal office in the immune system ’ s defense mechanisms against pathogens and their associated products . These Y-shaped proteins are specifically tailor to recognize and knock off alien invaders , see to it the host ’ sec security against several infection . Herein , we dig into the multifaceted functions of antibodies :

1. Neutralization: One of the principal function of antibody is neutralization . By binding directly to pathogens or their toxins , antibodies can suppress their power to attach to and infect host cells . For example , antibodies specific to bacterial toxins can block the toxin ’ s interaction with host cells , thereby knock off its harmful result . Similarly , antibody can forestall virus or bacteria from initiate infections by hinder their attachment to direct cells .
2. Opsonization: Opsonization is a process where antibody coat pathogens , enhance their realization and intake by phagocytic cell , such as macrophages and neutrophils . When antibodies tie to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can too activate the complement system , a series of protein that operate in tandem to destroy pathogens . Upon binding to pathogens , sure antibodies can trigger the complement cascade , leading to the formation of the membrane approach complex ( MAC ) that at once lyses certain bacteria and viruses . Additionally , some by-product of the complement cascade , like C3b , can opsonize pathogens , further enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological part , antibodies service as crucial tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insight into the individual ’ s humoral immunity status . Technique like radial immunodiffusion and immunoelectrophoresis are commonly employed to assess these antibodies , help in the diagnosis and monitoring of several disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the product of antibodies by B cell in reply to foreign antigen . This mechanism has live instrumental in defending against various pathogens throughout account . Here , we elucidate two discrete instance of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical records , include the discovery of smallpox wound on the mama of Pharaoh Ramses V , hint the ancient prevalence of this deadly disease . Smallpox have catastrophic impacts , especially decimating indigenous population in the Americas and Australia . Still , by the end of 1979 , a global vaccination campaign successfully eradicated the , marking a massive accomplishment in the annals of medicine .

The ancestry of vaccination can exist follow back to Edward Jenner ’ s sharp observation regarding the resistor of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ sec study , variolation , a practice call for the intentional introduction of pus from smallpox victims into sound individuals , was employed as a fundamental shape of inoculation . While the underlying mechanism of the secondary humoral immune response cost not yet understood , the principle of cause a mild infection to confer next protection cost recognized .

Jenner ’ s groundbreaking experiment call for the inoculation of a youthful boy with pus derive from cowpox sores of a milkmaid . Unusually , the boy demonstrate immunity to subsequent smallpox photograph , put the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing undermine or inactivated pathogens , innovative approach exist necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector scheme . Employ a genetically modified chimpanzee cold virus , know to evoke robust immune reception , the vaccine introduce the SARS-CoV-2 spike protein into the human torso . This foreign protein set off the primary humoral response , culminating in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines deliver the genetic design for the COVID-19 spike protein instantly into cells . The cells then synthesize the spike protein , initiating the humoral immune response . Contrary to some misconception , mRNA vaccines cause not alter human DNA . Rather , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and directly initiating translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system is a complex network of cell and proteins that defend the torso against pathogens . It can exist broadly categorized into two chief type : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and function . Here , we define the differences between these two branch of the immune reception .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies raise	Yes	No
Set off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ suffer for membranous .	TCR receptors
Accessory receptors involve	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigens equal make out . )	Yes ( Antigens live first work on and then presented by MHC of antigen-presenting cell )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cells	No	Yes

Quiz

Which cells equal primarily responsible for producing antibodies in the humoral immune response ?
a ) T cells
b ) Macrophages
100 ) B cells
d ) Dendritic cell

Show answer

Which type of immunity equal bestow by the production of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

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Which of the following is NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

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The primary immune reception is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

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Which of the pursuit is a characteristic of the secondary humoral immune reception ?
a ) Slower onset than the primary response
b ) Abject antibody concentration than the primary response
100 ) Product of memory B cell
d ) Absence of IgG product

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Which type of cells present antigen to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cell
d ) Memory cells

Show reply

Which antibody is primarily found in mucosal surface and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

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Which of the following be NOT a characteristic of monoclonal antibody ?
a ) Produced by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic applications

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The procedure by which antibody enhance the phagocytosis of pathogens cost called :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the pursuit is the primary function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
c ) Facilitate phagocytosis by bind to Fc receptors on phagocytic cells
d ) Inducing direct cell lysis

Show response

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA mode : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

• In the helper T cell-independent pathway , B cell proliferation occurs without the need for IL-4 and IL-6 stimulation . This solution in the production of plasma B cells but not memory B cell .
• In the assistant T cell-dependent pathway , IL-4 and IL-6 are essential for B cell proliferation . This process produces both plasma B cell and memory B cells , which can final up to 10-20 years . Upon re-infection with the same antigen , these memory B cells swiftly induce antibody product .

Antibody-Antigen Interaction: The interaction between an antibody and its specific antigen is term the antibody-antigen response . This highly specific chemical interaction was first detailed by Richard J. Goldberg in 1952 , take some to refer to it as “ Goldberg ’ s theory. ” Follow this interaction , an agglutination procedure can pass , where cross-linking of antigen by antibodies result in a clumping appearance .

Implication of the Antibody-Antigen Reaction :The antibody-antigen reaction is cardinal to humoral immunity . By consistently initiate this reaction against foreign agents , the torso strengthen its immune defense , ensuring robust security against potential threats .

Element of Humoral immunity

Humoral immunity , a vital weapon of the adaptive immune system , is mainly mediated by antibodies . To full hold on the intricacies of humoral immune responses , it ’ s essential to delve into its key components .

1. Pathogens :Pathogens are harmful microorganism distinct from the body ’ s normal plant . While many bacteria coexist harmoniously within us , pathogens equal alien entity that can induce disease . It ’ s essential to distinguish between these harmful invaders and the benign microorganisms that typically reside in our system .
2. Antigens :Antigen are specific protein or molecule deliver on the surface of pathogens . They can cost proteins , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acids , or lipids . Not every antigen triggers an immune reception . Those that do are termed immunogens , with protein and polysaccharides cost the nearly mutual . The fighting region of an antigen , responsible for bind to immune cell and antibody receptors , cost know as the epitope .
3. Haptens :Haptens cost smaller molecules that , on their own , don ’ t present as utter antigen . However , when merge with bearer proteins , they can elicit an immune answer . A classical lesson is urushiol from poison ivy , which turn immunogenic when bound to clamber proteins .
4. Lymphoid Organs :These are specialized structure where immune cells spring up , mature , and get trigger . Primary lymphoid organ , like the red bone center and thymus gland , facilitate the formation and maturation of lymphocytes . Secondary lymphoid organs , including lymph nodes , spleen , and tonsils , are sites where lymphocytes be set off .
5. Antigen-Presenting Cells ( APCs ) :APCs play a pivotal role in the immune reaction by capture pathogens , work on them , and introduce their antigens on their surface to T cell . This demonstration be crucial for the activation of T cell , bridging innate and adaptive immunity .
6. T Cell :T lymphocytes , or T cells , are cardinal actor in both innate and adaptive immunity . While directly objective and destroy infected cells , helper T cell act as intermediaries , releasing cytokines to pull in B cell and bridge the gap between the two immune systems .
7. B Cells :B cell , or B lymphocytes , serve multiple use . They can play as APCs , secrete cytokines , and most importantly , produce antibodies . Upon activation , B cells can distinguish into plasma cells , which produce antibody , or memory cells , which provide long-term immunity against specific pathogens .
8. Antibody :Antibody , or immunoglobulins , are the principal effectors of humoral immunity . They discern and neutralize pathogens in respective ways , such as direct binding , neutralization , or promoting phagocytosis . There are five main types of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific role in the immune reaction .

In conclusion , humoral immunity is a multifaceted system represent respective components , each playing a unique role in defending the torso against foreign invaders . Understand these components and their interactions exist essential for appreciating the complexity and efficiency of our immune system .

Phases/Humoral Immune response step

Main Phase/Primary humoral immune response

The humoral immune response , a pivotal portion of the adaptive immune system , operates in distinct phases to insure an effective defense against alien pathogens . The principal phase , also known as the initial response , is characterize by a series of systematic and coordinated case that go on upon the body ’ s first skirmish with an antigen .

1. Antigen Encounter and Processing :Upon the initial impinging with a alien pathogen , antigen-presenting cells ( APCs ) capture and internalize the antigen . These APCs then digest the antigen , convince specific fragments into major histocompatibility complex class II ( ) surface proteins .
2. T Helper Cell Activation :The MHC II surface protein , now presenting the antigen fragment , are recognize by T helper cells . This realization cost a crucial step , as it see to it that the immune system responds specifically to the foreign antigen .
3. Cytokine Product :Upon recognizing the MHC II-antigen composite , T helper cell make cytokines , signal molecules that play a vital purpose in regulate the immune answer .
4. B Cell Activation and Differentiation :Influenced by the cytokines let go by T help cell , naïve B cell become activated . Once activated , these B cell undergo differentiation , giving raise to two primary cell types : plasma cell and memory B cells .
5. Antibody Product :The newly take form plasma cell venture on their primary function : the product and secretion of antibody . Initially , IgM antibodies are raise . Still , if the pathogen hang on still after crest IgM secretion , the immune system may too produce IgG or IgA antibodies to bolster the defense .
6. Temporal Dynamics :The principal phase equal not instantaneous . Following the initial exposure to an antigen , there ’ sec a lag period , typically wander from 7 to 10 day , before peak antibody levels exist reached in the serum . This lag can vary base on the nature of the antigen ; for instance , sure antigen might make a answer within hours , while others might take weeks . Factors influence this period include the antigen ’ s dosage , its mode of rescue ( oral or parenteral ) , and its integral properties .
7. Antibody Dynamics :During this primary answer , the concentration of antibody in the serum rises for several weeks before gradually go down . While IgM degree lean to wane more quickly , IgG degree persist for a more extensive period , extend support protection .

In summary , the principal stage of the humoral immune reply is a meticulously orchestrated series of events that assure the torso mounts an effective defense against new pathogens . This stage set the foundation for subsequent immune responses , ensuring that the torso equal good prepare for next encounters with the same antigen .

Secondary Phase/Secondary humoral immune response

The secondary humoral immune answer , too referred to as the anamnestic or memory response , represents the immune system ’ sec enhance reaction to a previously run into pathogen . This heightened response exist facilitate by memory B cell , which are generated during the primary exposure to the antigen and can hang on for extended durations , rate from week to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly recognize the antigenic determinants of the microorganism . Their previous skirmish with the antigen equip them with a heightened state of readiness , enable a rapid and efficient response .
2. Clonal Expansion and Differentiation :Upon antigen recognition , memory B cells undergo clonal expansion , producing a big number of highly-specific plasma cells . These plasma cell are tailor to produce antibody that specifically direct the encountered antigen .
3. Enhanced Antibody Product :In the secondary response , there is a marked growth in the production of antibodies , pass by the point watch during the main answer by over a thousand-fold . While IgG cost the predominant immunoglobulin produced , there equal also a noted product of IgM , IgA , and IgE .
4. Rapid Peak Response :One of the hallmarks of the secondary humoral immune response equal the swift attainment of peak antibody levels , typically within a simple 3 to 5 day post-exposure . This contrast with the longer lag period observed during the primary reply .
5. Persistency of Memory Cells :The enhanced and rapid secondary response can equal attributed to the presence of antigen-specific memory cell , which persist post the initial antigen skirmish . These cells undergo extensive proliferation , generate a vast array of specific B cell and plasma cell that mediate the secondary response .
6. Qualitative Differences in Antibody Product :While the measure of IgM develop during the secondary reception cost like to that of the primary answer , there is a significant growth in the product of IgG . Furthermore , the produce IgG persists for a more extensive period during the secondary reception .
7. Enhanced Antibody Affinity :Antibodies develop during the secondary reply exhibit a high affinity for the antigen , meaning they tie more tightly and exist less likely to dissociate . This increase binding strength arises from somatic hypermutation , a procedure where changes go on in the DNA encoding the antigen-binding site , optimizing antibody-antigen interaction .

Destiny of Antigen in Tissues

The lot of an antigen within the body is mostly find out by its mode of introduction . This trajectory and eventual localization of the antigen act a pivotal part in form the immune reception .

1. Subcutaneous Establishment :When antigen are introduce subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which run out the interstitial fluid from , catch these antigen and transports them to the lymph nodes . Here , specialize immune cell can distinguish , procedure , and start an immune answer against these antigens . Merely a minuscule fraction of the antigen reaches the spleen , a secondary lymphoid organ , when introduced via this route .
2. Intravenous Establishment :Intravenous pitch of antigens paints a different painting . Such antigens live chiefly base in systemic organs like the spleen , liver , bone center , kidneys , and lung . The direct entry into the bloodstream let these antigens to circulate widely and interact with several tissues . Interestingly , despite the extensive vascular network connecting them , lymph nodes exhibit minimum presence of these intravenously introduce antigen .
3. Antigen Clearance :A significant percentage of the antigens , no matter of their route of entry , undergo degradation . Reticuloepithelial cell , which form part of the torso ’ s mononuclear phagocyte system , bring a essential part in this procedure . They engulf and pause down these antigen , see to it that the torso is not overcome . Post degradation , around three-quarters of these antigens are excreted via the urine , effectively eliminating them from the torso .

Product of Antibodies

The intricate procedure of antibody synthesis cost a testament to the body ’ s organize defense mechanism . This synthesis is orchestrated through the collaborative effort of three chief cell types : macrophages , T helper cell , and B cells .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cell , sort out as APCs , cost pivotal in presenting antigens to immunocompetent cell . For many T-cell-dependent antigens , including protein and erythrocytes , macrophages be essential for work on the antigen before antibody production can start out . However , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cells expose the antigen on their surface , either in its native figure or as processed fragment .
2. Macrophages and Optimal Antigen Exposure :Macrophages play a nuanced role in regulate the antigen dosage exposed to lymphocytes , insure the optimum activation of immunological response . Following macrophage processing , antigen fragments , in conjunction with grade II MHC proteins , surface on the macrophages . This complex then employ specific receptors on help T cell .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein complex , helper T cells release cytokines . These cytokines , including Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cells to produce antigen-specific antibody . The B cells , once trigger , undergo clonal proliferation , differentiate into plasma cell . These plasma cells are the factory produce specific immunoglobulins or antibody , which bring roles such as knock off toxins and viruses and facilitate pathogen uptake by phagocytic cells .
4. T-cell-independent Antigen :While helper T cells are indispensable for most antibody production , certain chemicals , like polysaccharides , can activate B cell without T cell assistance . These live term T-cell-independent antigen . Still , these antigens prompt B cell to produce just IgM antibodies . The synthesis of early antibody type , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which are exclusively give rise by T helper cells .
5. B Cell Antigen Recognition :B cells hire their surface IgM as an antigen receptor , enable them to recognize a plethora of antigen , from proteins to lipids and nucleic acid . This broad recognition spectrum empowers B cell to yield antibodies against a huge array of molecule . However , for protein fragments to cost introduce to helper T cells , they must live associated with class II MHC protein .

Theories of antibody formation

The genesis of antibody , essential components of the immune system , has live a subject of scientific wonder and debate . Over time , two primary theory make come out to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory posits that an immunocompetent cell inherently possesses the capacity to develop a myriad of antibodies . The antigen , upon introduction , instruct these cells to yield specific antibody complementary to itself . Two sub-theories further elucidate this conception :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , guiding the formation of the antibody . The resulting antibody molecule adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cells , get a hereditary change . This change involves the integration of the antigenic determinant ’ s genocopy into the genome , which cost then passed on to progeny cell . Still , this explanation get lost favor over time .

B . Selective Theories

These theories advise that the body already possess a repertoire of possible antibody , and the introduction of an antigen merely choose the appropriate one . Three sub-theories further item this concept :

1. Slope Chain Theory:
   • Presented by Ehrlich in 1898 .
   • Argues that immunocompetent cells have come out receptors that can interact with antigens possessing complementary side chains . Upon antigen introduction , these receptors bind with the antigen , become inactive . To compensate , the cell overproduces similar receptors , which are then relinquish as antibodies .
2. Theory:
   • Suggest by Jerne in 1955 .
   • Suggests that during fetal development , the torso produce globulin particle against all conceivable antigens . Upon antigen introduction , the antigen selectively tie to the almost complementary globulin particle , stimulating the product of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduced by Burnet in 1957 .
   • Proposes that during fetal evolution , a huge array of immunologically competent cell clones , each with a unique antibody pattern , is produced . Each of these cells convey membrane receptors specific to a peculiar antigen , determined before the cell ’ s photo to the antigen . Upon antigen introduction , the cell with the matching receptor equal trigger , proliferates , and produce the corresponding antibody . This theory , widely accepted today , offers insights into immunological specificity , memory , and the ability to distinguish between self and non-self .

Factors regard product of antibody

The production of antibodies , a pivotal aspect of the immune response , cost influence by a myriad of factor . Understanding these determinants is crucial for both basic immunology and clinical application . Herein , we delve into the significant component that modulate antibody product :

1. Genetic Factors:
   • The genetic makeup of an dictates its response to antigens . Some equal responders , producing antibody upon exposure , while others , term nonresponders , do not .
   • The immune response ( Ir ) gene , place on the short weapon of chromosome six , governs these variations .
2. Age:
   • Neonates and embryos exhibit an underdeveloped immune competence .
   • Full immunological competence , marked by the development of lymphoid organs , is achieved by ages 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acids and vitamin , can restrict antibody production .
4. Road of Antigen Administration:
   • The mode of antigen delivery act a pivotal role in eliciting an immune reaction . Parenteral administration typically induces a more robust reply equate to oral or nasal route .
5. Dose of Antigen:
   • An optimum dose of antigen live essential for a maximum immune response . Extremely high or low dosage can lead to immunological paralysis , a state of dilute immune responsiveness .
6. Multiple Antigen:
   • Simultaneous establishment of multiple antigen can lead to vary antibody reception due to antigenic competitor . The precise formulation and proportion of these antigen are essential for achieve hope effect .
7. Adjuvants:
   • Adjuvants be meaning that enhance the immunogenicity of antigen by prolonging antigenic stimulation . Examples include Freund ’ s incomplete and all over adjuvants , aluminum salt , and early substances like silica particle .
8. Immunosuppressive Agents:
   • These agent moisten the immune reception and live utilize in scenarios like transplantation surgeries . Examples include :
     • X-irradiation: Impedes antibody product place 24 hr of photo .
     • Radiometric Drugs: Specifically target B cells , inhibiting their replication .
     • Corticosteroids: Decrease the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets circulating lymphocytes , sparing those in lymphoid organ .

Monoclonal Antibody

Monoclonal antibodies ( mAbs ) are a grade of antibody derived from a single cell ancestry , assure their homogeneity . Unlike polyclonal antibodies , which are develop by multiple plasma cell clones and live heterologous in nature , monoclonal antibodies live specific to a single antigenic determinant .

Origin and Distinction: Monoclonal antibodies develop from condition like multiple myeloma , where a singular plasma cell clone produces antibodies against a specific antigenic determinant . This specificity contrasts with polyclonal antibody , which arise from respective plasma cell clones in reply to an antigen .

Production Methodology: The pioneering method for monoclonal antibody production exist introduced by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique involved the creation of hybridomas , which be make by fusing myeloma cell with antibody-producing cells . These hybridomas , once established , can indefinitely produce monoclonal antibodies , prove priceless for research and diagnostic intention .

The process involves :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ sec spleen with mouse myeloma cell that miss the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion employ agents like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT medium ) that supports hybrid cell increase but inhibits the growth of parent cell .
5. Shield the result cell clones for antibody product against the target antigen .
6. Choose and perpetually culturing the clones that produce the desire antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies posed challenge for therapeutic role in humans . Accordingly , advancements result to the evolution of human monoclonal antibodies , include chimeric antibodies . These chimeric antibodies , compose of human constant regions and mouse variable regions , equal be search for leukemia treatment . Furthermore , they can be employed to target tumor cells either by present toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Affair of Antibodies

Antibodies , too known as immunoglobulins , run a pivotal role in the immune system ’ s defense mechanism against pathogens and their associated production . These Y-shaped proteins are specifically tailored to recognize and knock off alien invaders , insure the host ’ s security against various infection . Herein , we dig into the multifaceted office of antibody :

1. Neutralization: One of the chief purpose of antibody is neutralization . By stick to straight to pathogens or their toxins , antibodies can suppress their ability to attach to and infect horde cells . For instance , antibodies specific to bacterial toxins can block the toxin ’ s interaction with horde cells , thereby neutralize its harmful effects . Likewise , antibody can prevent virus or bacteria from lead up infection by hinder their attachment to target cells .
2. Opsonization: Opsonization is a process where antibodies coat pathogens , enhancing their realization and intake by phagocytic cell , such as macrophages and neutrophil . When antibody bind to pathogens , the Fc area of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can too activate the complement system , a series of protein that operate in tandem to ruin pathogens . Upon binding to pathogens , certain antibodies can touch off the complement cascade , head to the formation of the membrane approach complex ( MAC ) that straight lyses certain bacteria and viruses . Additionally , some by-product of the complement cascade , like C3b , can opsonize pathogens , further enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological role , antibody suffice as crucial tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can leave insights into the individual ’ sec humoral immunity status . Technique like radial immunodiffusion and immunoelectrophoresis are ordinarily utilize to evaluate these antibody , assist in the diagnosis and monitoring of various disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , be characterized by the production of antibody by B cells in response to foreign antigens . This mechanism has been instrumental in oppose against several pathogens throughout account . Here , we clear up two discrete examples of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox wound on the mummy of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox get catastrophic impacts , peculiarly decimating indigenous population in the Americas and Australia . However , by the goal of 1979 , a global vaccination campaign successfully eradicated the , marking a monumental achievement in the annals of medicine .

The origins of vaccination can exist trace back to Edward Jenner ’ s sharp observation involve the resistor of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ sec work , variolation , a pattern involving the intentional introduction of pus from smallpox victim into sound individual , equal employed as a fundamental kind of inoculation . While the underlying mechanisms of the secondary humoral immune response live not yet understood , the rationale of inducing a meek infection to bestow next security equal recognized .

Jenner ’ s groundbreaking experiment involved the inoculation of a young boy with pus descend from cowpox sores of a milkmaid . Remarkably , the son exhibited immunity to subsequent smallpox photo , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employ weakened or inactivated pathogens , innovative approach were necessitated due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine hire a viral vector strategy . Employ a genetically modified chimpanzee cold virus , known to elicit robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human torso . This alien protein touch off the chief humoral reaction , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines have the genetic design for the COVID-19 spike protein directly into cells . The cells then synthesize the spike protein , lead up the humoral immune reply . Contrary to some misconception , mRNA vaccines do not change human DNA . Rather , they harness the cellular machinery for protein synthesis , bypassing the transcription stage and directly initiating translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system be a complex network of cells and protein that defend the body against pathogens . It can cost broadly categorized into two primary types : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and purpose . Hither , we specify the differences between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody develop	Yes	No
Trigger by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is need	No ( Unprocessed antigen are recognized . )	Yes ( Antigens are first processed and then deliver by MHC of antigen-presenting cell )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cells	No	Yes

Quiz

Which cells are primarily responsible for give rise antibody in the humoral immune response ?
a ) T cell
b ) Macrophages
c ) B cell
d ) Dendritic cell

Show answer

Which type of immunity is conferred by the production of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show reply

Which of the pursuit equal NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show solution

The principal immune response is characterize by the production of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show response

Which of the pursuit is a characteristic of the secondary humoral immune response ?
a ) Slower onset than the main response
b ) Abject antibody concentration than the primary response
100 ) Product of memory B cell
d ) Absence of IgG product

Show reply

Which type of cell present antigens to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cells ( APCs )
100 ) Plasma cell
d ) Memory cell

Show answer

Which antibody is primarily get in mucosal surface and secretion ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the pursuit is NOT a characteristic of monoclonal antibody ?
a ) Raise by a single clone of cells
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Use in diagnostic and therapeutic applications

Show answer

The process by which antibodies enhance the phagocytosis of pathogens cost called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the pursuit exist the main function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Significance of the Antibody-Antigen Response :The antibody-antigen response cost cardinal to humoral immunity . By consistently initiating this reaction against foreign agents , the torso fortify its immune defense , ensure robust security against potential menace .

Constituent of Humoral immunity

Humoral immunity , a vital weapon of the adaptive immune system , exist chiefly mediated by antibodies . To full hold on the intricacies of humoral immune reaction , it ’ s essential to dig into its key components .

1. Pathogens :Pathogens are harmful microorganism distinct from the body ’ s normal plant . While many bacteria coexist harmoniously within us , pathogens live alien entities that can cause disease . It ’ s essential to differentiate between these harmful invaders and the benign microorganisms that typically occupy in our system .
2. Antigens :Antigens be specific protein or molecule introduce on the surface of pathogens . They can be protein , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acid , or lipids . Not every antigen triggers an immune reaction . Those that serve be termed immunogens , with proteins and polysaccharides exist the most common . The active region of an antigen , responsible for binding to immune cell and antibody receptors , is know as the epitope .
3. Haptens :Haptens are smaller molecules that , on their own , don ’ t present as utter antigen . However , when merge with bearer proteins , they can elicit an immune reception . A classic example equal urushiol from poison ivy , which becomes immunogenic when bound to skin protein .
4. Lymphoid Organs :These are specialized structure where immune cell train , mature , and make activated . Principal lymphoid organs , like the red bone center and thymus gland , facilitate the formation and maturation of lymphocytes . Secondary lymphoid organ , including lymph nodes , spleen , and tonsils , are sites where lymphocytes be activated .
5. Antigen-Presenting Cells ( APCs ) :APCs act a pivotal purpose in the immune reaction by capture pathogens , work on them , and deliver their antigens on their surface to T cells . This demonstration equal essential for the activation of T cell , bridge innate and adaptive immunity .
6. T Cells :T lymphocytes , or T cells , are central players in both innate and adaptive immunity . While immediately target and destroy septic cells , helper T cells act as intermediaries , releasing cytokines to pull in B cells and bridge the gap between the two immune systems .
7. B Cells :B cells , or B lymphocytes , do multiple purpose . They can behave as APCs , secrete cytokines , and most importantly , develop antibodies . Upon activation , B cell can distinguish into plasma cells , which produce antibody , or memory cell , which supply long-run immunity against specific pathogens .
8. Antibodies :Antibodies , or immunoglobulins , equal the main effectors of humoral immunity . They distinguish and knock off pathogens in respective means , such as direct binding , neutralization , or advance phagocytosis . There live five main types of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific role in the immune response .

In decision , humoral immunity is a multifaceted system make up several element , each meet a unique role in oppose the body against foreign invaders . Understanding these components and their interaction is crucial for appreciate the complexity and efficiency of our immune system .

Phases/Humoral Immune reply step

Chief Phase/Primary humoral immune reaction

The humoral immune response , a pivotal element of the adaptive immune system , operates in distinct phases to assure an efficient defense against alien pathogens . The chief stage , also known as the initial response , live characterized by a series of systematic and coordinated events that occur upon the torso ’ s first skirmish with an antigen .

1. Antigen Encounter and Processing :Upon the initial contact with a foreign pathogen , antigen-presenting cell ( APCs ) capture and internalize the antigen . These APCs then stand the antigen , converting specific fragments into major histocompatibility complex grade II ( ) surface protein .
2. T Helper Cell Activation :The MHC II surface protein , now presenting the antigen fragment , are recognized by T helper cell . This recognition exist a essential step , as it ensures that the immune system react specifically to the alien antigen .
3. Cytokine Product :Upon recognize the MHC II-antigen complex , T assistant cell produce cytokines , signal molecule that work a critical role in regulate the immune response .
4. B Cell Activation and Differentiation :Influenced by the cytokines release by T helper cell , naïve B cells become activated . Once activated , these B cell undergo differentiation , pay raise to two main cell types : plasma cells and memory B cells .
5. Antibody Production :The newly organize plasma cells embark on their principal function : the product and secretion of antibodies . Initially , IgM antibody are develop . However , if the pathogen remain even after top IgM secretion , the immune system may too grow IgG or IgA antibody to bolster the defense .
6. Temporal Dynamics :The primary stage is not instantaneous . Following the initial exposure to an antigen , there ’ sec a lag period , typically wander from 7 to 10 day , before peak antibody levels exist reached in the serum . This lag can change base on the nature of the antigen ; for example , sure antigen might cause a reaction within hr , while others might take weeks . Factors influence this period include the antigen ’ sec dose , its mode of delivery ( oral or parenteral ) , and its underlying property .
7. Antibody Dynamics :During this main reception , the concentration of antibodies in the serum rises for various weeks before step by step refuse . While IgM point run to wane more rapidly , IgG levels persist for a more extended period , offering maintain security .

In summary , the primary stage of the humoral immune response cost a meticulously orchestrated series of events that ensure the body mounts an effective defense against novel pathogens . This phase lay the foundation for subsequent immune responses , ensuring that the body cost good educate for future encounter with the same antigen .

Secondary Phase/Secondary humoral immune answer

The secondary humoral immune response , also relate to as the anamnestic or memory response , represents the immune system ’ s enhance reaction to a previously run into pathogen . This heightened response is facilitated by memory B cells , which be generated during the main exposure to the antigen and can hang on for extended durations , range from week to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cells swiftly discern the antigenic determinants of the microorganism . Their former encounter with the antigen equips them with a heightened state of readiness , enabling a rapid and effective response .
2. Clonal Expansion and Differentiation :Upon antigen realization , memory B cells undergo clonal expansion , producing a large number of highly-specific plasma cell . These plasma cell are tailored to produce antibody that specifically target the encountered antigen .
3. Enhanced Antibody Product :In the secondary response , there exist a marked increase in the production of antibodies , transcend the levels observe during the chief reply by over a thousand-fold . While IgG is the predominant immunoglobulin produced , there is too a notable product of IgM , IgA , and IgE .
4. Rapid Peak Answer :One of the trademark of the secondary humoral immune reception is the swift attainment of peak antibody levels , typically within a mere 3 to 5 day post-exposure . This contrast with the longer lag period observed during the main response .
5. Persistence of Memory Cells :The enhanced and rapid secondary reaction can live attribute to the presence of antigen-specific memory cells , which persist post the initial antigen skirmish . These cells undergo extensive proliferation , generating a vast array of specific B cells and plasma cell that mediate the secondary reply .
6. Qualitative Differences in Antibody Production :While the amount of IgM produced during the secondary response live like to that of the principal response , there is a substantial growth in the production of IgG . Furthermore , the produced IgG persists for a more extensive period during the secondary reply .
7. Enhanced Antibody Affinity :Antibodies produced during the secondary reply display a high affinity for the antigen , meaning they tie more tightly and are less probable to dissociate . This increased binding strength arises from somatic hypermutation , a process where alteration pass in the DNA encoding the antigen-binding site , optimizing antibody-antigen interactions .

Destiny of Antigen in Tissues

The luck of an antigen within the torso equal mostly determine by its style of introduction . This trajectory and eventual localization of the antigen play a pivotal use in determine the immune reception .

1. Subcutaneous Organization :When antigens cost introduced subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which run out the interstitial fluid from , catch these antigen and transport them to the lymph nodes . Hither , specialize immune cells can recognize , process , and start an immune answer against these antigen . Solely a minuscule fraction of the antigen achieve the spleen , a secondary lymphoid organ , when introduce via this route .
2. Intravenous Establishment :Intravenous pitch of antigens paint a different picture . Such antigens are chiefly found in systemic organs like the spleen , liver , bone marrow , kidneys , and lungs . The direct entry into the bloodstream let these antigen to circulate widely and interact with respective tissue . Interestingly , despite the extensive vascular network connect them , lymph nodes display minimal presence of these intravenously bring in antigen .
3. Antigen Clearance :A significant component of the antigens , regardless of their route of entry , undergo degradation . Reticuloepithelial cells , which spring part of the torso ’ s mononuclear phagocyte system , run a essential role in this process . They engulf and break down these antigen , ensuring that the body live not overwhelmed . Post degradation , around three-quarters of these antigen exist excreted via the urine , in effect get rid of them from the torso .

Production of Antibodies

The intricate procedure of antibody synthesis is a testament to the torso ’ sec coordinated defense mechanism . This synthesis be orchestrated through the collaborative efforts of three main cell type : macrophages , T helper cells , and B cell .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , separate as APCs , be pivotal in deliver antigens to immunocompetent cells . For many T-cell-dependent antigen , including protein and erythrocytes , macrophages live essential for work on the antigen before antibody production can begin . However , T-cell-independent antigen bypass this macrophage processing . Post-processing , macrophages and dendritic cells exhibit the antigen on their surface , either in its native form or as processed fragments .
2. Macrophages and Optimal Antigen Exposure :Macrophages play a nuanced office in regulate the antigen dosage disclose to lymphocytes , see to it the optimum activation of immunological responses . Follow macrophage processing , antigen fragment , in conjunction with class II MHC protein , surface on the macrophages . This complex then engages specific receptors on helper T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein complex , helper T cells release cytokines . These cytokines , including Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cell to produce antigen-specific antibodies . The B cells , once trigger , undergo clonal proliferation , differentiate into plasma cells . These plasma cell cost the factory produce specific immunoglobulins or antibody , which play purpose such as neutralizing toxins and viruses and facilitating pathogen uptake by phagocytic cells .
4. T-cell-independent Antigens :While helper T cell are indispensable for most antibody production , sure chemicals , like polysaccharides , can activate B cells without T cell assistance . These equal termed T-cell-independent antigen . Even so , these antigen prompt B cells to grow simply IgM antibody . The synthesis of early antibody types , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which be exclusively give rise by T help cells .
5. B Cell Antigen Recognition :B cell use their surface IgM as an antigen receptor , enable them to recognize a plethora of antigen , from protein to lipids and nucleic acid . This broad recognition spectrum empowers B cell to generate antibody against a vast array of molecules . Even so , for protein fragments to live demonstrate to helper T cells , they must be associated with class II MHC protein .

Theories of antibody formation

The genesis of antibodies , essential element of the immune system , have cost a subject of scientific curiosity and debate . Over time , two primary theories get issue to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory state that an immunocompetent cell inherently possesses the capability to give rise a myriad of antibodies . The antigen , upon introduction , instruct these cells to generate specific antibodies complementary to itself . Two sub-theories further elucidate this conception :

1. Direct Template Theory:
   • Advise by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants act as a template , direct the formation of the antibody . The result antibody molecule adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cells , have a hereditary change . This change involves the integration of the antigenic determinant ’ sec genocopy into the genome , which is then passed on to progeny cell . Still , this explanation own lost favor over time .

B . Selective Theory

These theories propose that the torso already possesses a repertoire of potential antibodies , and the introduction of an antigen merely selects the appropriate one . Three sub-theories further detail this conception :

1. Slope Chain Theory:
   • Present by Ehrlich in 1898 .
   • Argues that immunocompetent cell get surface receptors that can interact with antigens possessing complementary side chains . Upon antigen introduction , these receptors tie with the antigen , become passive . To compensate , the cell overproduces like receptors , which be then released as antibody .
2. Theory:
   • Proposed by Jerne in 1955 .
   • Suggests that during fetal development , the body produce globulin molecules against all conceivable antigen . Upon antigen introduction , the antigen selectively binds to the almost complementary globulin molecule , stimulating the production of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduced by Burnet in 1957 .
   • Proposes that during fetal development , a immense array of immunologically competent cell clones , each with a unique antibody practice , is produce . Each of these cells express membrane receptors specific to a special antigen , determined before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the match receptor is activated , proliferates , and produces the corresponding antibody . This theory , widely accepted today , extend insight into immunological specificity , memory , and the power to distinguish between self and non-self .

Factors affect product of antibody

The product of antibodies , a pivotal scene of the immune reaction , equal influenced by a myriad of factors . Understanding these determinants cost essential for both basic immunology and clinical application . Herein , we dig into the significant factors that regulate antibody product :

1. Genetic Element:
   • The genetic makeup of an dictates its answer to antigens . Some exist responders , give rise antibodies upon exposure , while others , term nonresponders , do not .
   • The immune reply ( Ir ) gene , settle on the short arm of chromosome six , governs these version .
2. Age:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , notice by the maturation of lymphoid organ , is achieved by years 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acid and vitamins , can restrict antibody production .
4. Road of Antigen Administration:
   • The way of antigen delivery meet a pivotal part in eliciting an immune response . Parenteral organization typically have a more robust reception compare to oral or nasal route .
5. Dose of Antigen:
   • An optimum dosage of antigen is essential for a maximum immune answer . Extremely high or humble doses can result to immunological paralysis , a state of reduce immune responsiveness .
6. Multiple Antigen:
   • Concurrent administration of multiple antigens can lead to change antibody answer due to antigenic competitor . The precise expression and proportion of these antigens are crucial for achieve want outcomes .
7. Adjuvants:
   • Adjuvants are substance that enhance the immunogenicity of antigens by prolong antigenic stimulus . Examples include Freund ’ s incomplete and all over adjuvants , aluminum salts , and early meaning like silica particle .
8. Immunosuppressive Agents:
   • These agents moisten the immune response and are apply in scenarios like transplantation surgeries . Examples include :
     • X-irradiation: Impedes antibody product place 24 hours of photograph .
     • Radiometric Drugs: Specifically target B cells , suppress their replication .
     • Corticosteroids: Lessen the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets circulating lymphocytes , sparing those in lymphoid organs .

Monoclonal Antibodies

Monoclonal antibody ( mAbs ) live a course of antibodies derived from a single cell lineage , ensuring their homogeneity . Unlike polyclonal antibodies , which be give rise by multiple plasma cell clones and are heterologous in nature , monoclonal antibodies live specific to a single antigenic determinant .

Source and Distinction: Monoclonal antibody spring up from conditions like multiple myeloma , where a funny plasma cell clone produces antibody against a specific antigenic determinant . This specificity contrasts with polyclonal antibody , which arise from respective plasma cell clones in response to an antigen .

Product Methodology: The pioneering method for monoclonal antibody product exist bring in by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique demand the creation of hybridomas , which are form by fusing myeloma cell with antibody-producing cell . These hybridomas , once lay down , can indefinitely raise monoclonal antibodies , prove priceless for inquiry and diagnostic purposes .

The procedure involves :

1. Inoculating an beast , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ s spleen with mouse myeloma cells that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion using agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT media ) that defend hybrid cell growth but inhibits the increase of parent cell .
5. Screening the result cell clones for antibody production against the aim antigen .
6. Select and perpetually culturing the clones that produce the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies set challenges for therapeutic usage in human . Consequently , advancements led to the development of human monoclonal antibodies , including chimeric antibodies . These chimeric antibodies , composed of human constant regions and mouse variable regions , be being search for leukemia treatment . Furthermore , they can cost employed to direct tumor cells either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibodies

Antibodies , also know as immunoglobulins , work a pivotal office in the immune system ’ s defense mechanisms against pathogens and their associated production . These Y-shaped proteins are specifically tailored to recognize and neutralize foreign invaders , see to it the horde ’ s security against respective infection . Herein , we dig into the multifaceted affair of antibody :

1. Neutralization: One of the primary part of antibody be neutralization . By binding directly to pathogens or their toxins , antibodies can inhibit their power to bind to and infect host cell . For instance , antibodies specific to bacterial toxins can block the toxin ’ s interaction with host cells , thereby knock off its harmful effects . Likewise , antibodies can forestall viruses or bacteria from initiating infections by hinder their attachment to target cells .
2. Opsonization: Opsonization is a procedure where antibodies coat pathogens , enhance their recognition and intake by phagocytic cell , such as macrophages and neutrophils . When antibody bind to pathogens , the Fc part of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can also activate the complement system , a series of protein that operate in tandem to ruin pathogens . Upon bind to pathogens , certain antibody can trigger the complement cascade , result to the formation of the membrane approach composite ( MAC ) that directly lyses sure bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , further enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological roles , antibodies serve as crucial tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can supply insight into the individual ’ s humoral immunity status . Technique like radial immunodiffusion and immunoelectrophoresis live ordinarily utilize to evaluate these antibody , aiding in the diagnosis and monitoring of various disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , cost characterize by the product of antibody by B cells in reply to alien antigens . This mechanism hold been instrumental in defending against various pathogens throughout story . Here , we elucidate two discrete instance of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical disc , include the discovery of smallpox lesions on the mummy of Pharaoh Ramses V , indicate the ancient prevalence of this deadly disease . Smallpox had catastrophic impact , in particular decimating indigenous populations in the Americas and Australia . Still , by the end of 1979 , a global vaccination campaign successfully eradicated the , marking a monumental achievement in the annals of medicine .

The origin of vaccination can live traced back to Edward Jenner ’ s sharp observation regard the opposition of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ s work , variolation , a practice involving the intentional introduction of pus from smallpox victim into sound individuals , cost utilize as a fundamental pattern of inoculation . While the underlying mechanism of the secondary humoral immune answer live not yet understood , the principle of inducing a mild infection to confer future security equal recognized .

Jenner ’ s groundbreaking experiment call for the inoculation of a young boy with pus derived from cowpox sores of a milkmaid . Unusually , the son exhibited immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing weaken or inactivated pathogens , innovative approaches live necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector strategy . Utilizing a genetically modified chimpanzee cold virus , known to elicit robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human body . This foreign protein set off the chief humoral response , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines redeem the genetic design for the COVID-19 spike protein right away into cells . The cells then synthesize the spike protein , initiate the humoral immune response . Contrary to some misconception , mRNA vaccines do not alter human DNA . Or else , they harness the cellular machinery for protein synthesis , bypass the transcription phase and immediately initiating translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system is a complex network of cell and protein that oppose the torso against pathogens . It can be broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and functions . Hither , we delineate the differences between these two branch of the immune reply .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies develop	Yes	No
Set off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cell , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors demand	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigens are discern . )	Yes ( Antigen live first processed and then presented by MHC of antigen-presenting cell )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cells	No	Yes

Quiz

Which cells cost chiefly responsible for produce antibodies in the humoral immune reply ?
a ) T cell
b ) Macrophages
100 ) B cell
d ) Dendritic cells

Show result

Which type of immunity live bestow by the product of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show answer

Which of the following cost NOT a purpose of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

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The chief immune reply is characterized by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show solution

Which of the following be a characteristic of the secondary humoral immune response ?
a ) Dumb onset than the principal reaction
b ) Lower antibody concentration than the primary reply
100 ) Product of memory B cell
d ) Absence of IgG production

Show result

Which type of cell present antigens to immunocompetent cell ?
a ) T cells
b ) Antigen-presenting cell ( APCs )
c ) Plasma cell
d ) Memory cells

Show answer

Which antibody is chiefly see in mucosal surfaces and secretion ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show result

Which of the pursuit is NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cell
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Apply in diagnostic and therapeutic applications

Show response

The process by which antibody enhance the phagocytosis of pathogens exist called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the following is the principal occasion of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by bind to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show answer

FAQ

Reference

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Components of Humoral immunity

Humoral immunity , a critical sleeve of the adaptive immune system , be mainly mediated by antibody . To full hold on the intricacies of humoral immune responses , it ’ s essential to dig into its key components .

1. Pathogens :Pathogens are harmful microorganisms distinct from the torso ’ s normal plant . While many bacteria coexist harmoniously within us , pathogens exist foreign entity that can cause disease . It ’ s essential to distinguish between these harmful invaders and the benign microorganisms that typically reside in our system .
2. Antigens :Antigen equal specific proteins or molecules present on the surface of pathogens . They can cost proteins , glycoproteins , lipoproteins , polysaccharides , lipopolysaccharides , nucleic acid , or lipids . Not every antigen trigger an immune reply . Those that do cost term immunogens , with proteins and polysaccharides make up the most mutual . The fighting region of an antigen , responsible for binding to immune cell and antibody receptors , equal know as the epitope .
3. Haptens :Haptens be smaller particle that , on their own , don ’ t present as all over antigen . Still , when combined with carrier protein , they can arouse an immune response . A classical model is urushiol from poison ivy , which becomes immunogenic when bound to clamber proteins .
4. Lymphoid Organ :These are specialized structures where immune cell formulate , mature , and come activated . Principal lymphoid organs , like the red bone marrow and thymus gland , facilitate the formation and maturation of lymphocytes . Secondary lymphoid organ , including lymph nodes , spleen , and tonsils , are pose where lymphocytes live activated .
5. Antigen-Presenting Cells ( APCs ) :APCs play a pivotal part in the immune answer by capturing pathogens , work on them , and deliver their antigen on their surface to T cells . This presentation equal crucial for the activation of T cell , bridging innate and adaptive immunity .
6. T Cell :T lymphocytes , or T cells , equal central players in both innate and adaptive immunity . While right away mark and destroy infected cell , helper T cells act as intermediaries , release cytokines to attract B cells and bridging the spread between the two immune system .
7. B Cell :B cell , or B lymphocytes , serve multiple roles . They can play as APCs , secrete cytokines , and most importantly , give rise antibody . Upon activation , B cells can distinguish into plasma cell , which develop antibody , or memory cells , which provide long-term immunity against specific pathogens .
8. Antibodies :Antibody , or immunoglobulins , live the primary effectors of humoral immunity . They distinguish and neutralize pathogens in respective ways , such as direct binding , neutralization , or advance phagocytosis . There exist five main type of immunoglobulins : IgM , IgA , IgD , IgG , and IgE , each with a specific use in the immune reception .

In conclusion , humoral immunity exist a multifaceted system represent various components , each playing a unique use in oppose the torso against foreign invaders . Understanding these constituent and their interaction cost crucial for appreciate the complexity and efficiency of our immune system .

Phases/Humoral Immune reply measure

Primary Phase/Primary humoral immune response

The humoral immune response , a pivotal constituent of the adaptive immune system , operates in distinct phases to insure an effective defense against foreign pathogens . The primary phase , also known as the initial answer , is characterize by a series of systematic and coordinated events that go on upon the torso ’ s first encounter with an antigen .

1. Antigen Encounter and Processing :Upon the initial impinging with a foreign pathogen , antigen-presenting cells ( APCs ) capture and internalize the antigen . These APCs then digest the antigen , convince specific fragments into major histocompatibility complex class II ( ) surface proteins .
2. T Helper Cell Activation :The MHC II surface proteins , now presenting the antigen fragment , are recognized by T helper cell . This realization is a crucial pace , as it ensures that the immune system responds specifically to the alien antigen .
3. Cytokine Production :Upon recognizing the MHC II-antigen complex , T helper cell produce cytokines , signal particle that play a vital part in regulate the immune answer .
4. B Cell Activation and Differentiation :Influence by the cytokines released by T helper cell , naïve B cells become activated . Once activated , these B cell undergo differentiation , giving rise to two principal cell type : plasma cells and memory B cells .
5. Antibody Product :The newly formed plasma cells venture on their principal office : the product and secretion of antibody . Initially , IgM antibody live produced . Still , if the pathogen persists still after peak IgM secretion , the immune system may also grow IgG or IgA antibodies to bolster the defense .
6. Temporal Dynamics :The chief stage cost not instantaneous . Following the initial photograph to an antigen , there ’ s a lag period , typically range from 7 to 10 day , before peak antibody floor are reached in the serum . This lag can change base on the nature of the antigen ; for example , certain antigens might make a answer within hours , while others might take weeks . Factors influence this period include the antigen ’ s dosage , its style of delivery ( oral or parenteral ) , and its inherent properties .
7. Antibody Dynamics :During this chief reception , the concentration of antibody in the serum arise for various week before step by step go down . While IgM levels tend to go down more rapidly , IgG levels persist for a more extensive period , offering support protection .

In summary , the primary stage of the humoral immune reception is a meticulously orchestrated series of event that see the body mounts an efficient defense against new pathogens . This phase place the foundation for subsequent immune responses , ensuring that the torso equal good educate for future skirmish with the same antigen .

Secondary Phase/Secondary humoral immune answer

The secondary humoral immune response , also pertain to as the anamnestic or memory reply , represents the immune system ’ sec enhance reaction to a previously encounter pathogen . This heightened answer is facilitate by memory B cell , which cost generate during the main exposure to the antigen and can persist for lengthy duration , place from week to years .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly recognize the antigenic determinants of the microorganism . Their former skirmish with the antigen equip them with a heightened state of readiness , enable a rapid and efficient reply .
2. Clonal Expansion and Differentiation :Upon antigen recognition , memory B cell undergo clonal expansion , producing a big number of highly-specific plasma cells . These plasma cell equal tailored to give rise antibody that specifically target the encountered antigen .
3. Enhanced Antibody Production :In the secondary response , there exist a marked increase in the product of antibody , transcend the levels observed during the primary reaction by over a thousand-fold . While IgG cost the predominant immunoglobulin produced , there be also a famed production of IgM , IgA , and IgE .
4. Rapid Peak Response :One of the hallmarks of the secondary humoral immune response live the swift attainment of peak antibody levels , typically within a mere 3 to 5 days post-exposure . This contrasts with the longer lag period observe during the primary reaction .
5. Persistence of Memory Cells :The enhanced and rapid secondary response can be ascribe to the presence of antigen-specific memory cells , which prevail post the initial antigen encounter . These cells undergo extensive proliferation , generating a immense array of specific B cell and plasma cells that mediate the secondary response .
6. Qualitative Difference in Antibody Product :While the measure of IgM produced during the secondary response live like to that of the primary reception , there is a substantial growth in the product of IgG . Moreover , the give rise IgG persists for a more extended period during the secondary response .
7. Enhanced Antibody Affinity :Antibody produced during the secondary response display a higher affinity for the antigen , think of they bind more tightly and be less potential to divorce . This increase binding force arises from somatic hypermutation , a procedure where change go on in the DNA encoding the antigen-binding site , optimizing antibody-antigen interaction .

Lot of Antigen in Tissues

The destiny of an antigen within the torso be mostly determined by its way of introduction . This trajectory and eventual localization of the antigen play a pivotal role in shaping the immune reception .

1. Subcutaneous Administration :When antigen live bring in subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which drains the interstitial fluid from , captures these antigen and transports them to the lymph nodes . Hither , specialize immune cell can recognize , procedure , and initiate an immune response against these antigen . Merely a minuscule fraction of the antigen reaches the spleen , a secondary lymphoid organ , when introduce via this path .
2. Intravenous Organization :Intravenous rescue of antigens paints a different image . Such antigen are primarily found in systemic organs like the spleen , liver , bone marrow , kidney , and lung . The direct entrance into the bloodstream allows these antigens to circle widely and interact with several tissue . Interestingly , despite the extensive vascular network connecting them , lymph nodes exhibit minimal presence of these intravenously introduced antigens .
3. Antigen Clearance :A significant portion of the antigen , no matter of their route of entrance , undergo degradation . Reticuloepithelial cell , which form role of the body ’ s mononuclear phagocyte system , bring a crucial role in this process . They engulf and collapse down these antigen , ensuring that the torso is not overwhelmed . Post degradation , around three-quarters of these antigen exist excreted via the urine , in effect get rid of them from the body .

Production of Antibodies

The intricate process of antibody synthesis is a testament to the torso ’ s coordinated defense mechanism . This synthesis equal orchestrated through the collaborative efforts of three primary cell type : macrophages , T assistant cell , and B cell .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cell , classified as APCs , are pivotal in demonstrate antigen to immunocompetent cell . For many T-cell-dependent antigen , include proteins and red blood cell , macrophages exist essential for processing the antigen before antibody production can begin . However , T-cell-independent antigen bypass this macrophage processing . Post-processing , macrophages and dendritic cell exhibit the antigen on their surface , either in its native form or as processed fragments .
2. Macrophages and Optimal Antigen Photograph :Macrophages act a nuanced purpose in regulate the antigen dosage exposed to lymphocytes , check the optimum activation of immunological reception . Follow macrophage processing , antigen fragments , in conjunction with class II MHC proteins , surface on the macrophages . This complex then pursue specific receptors on helper T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein complex , helper T cells release cytokines . These cytokines , including Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cell to produce antigen-specific antibodies . The B cell , once activated , undergo clonal proliferation , differentiating into plasma cell . These plasma cell live the factories develop specific immunoglobulins or antibodies , which run roles such as neutralizing toxins and virus and facilitating pathogen uptake by phagocytic cells .
4. T-cell-independent Antigen :While helper T cells are indispensable for most antibody production , sure chemical , like polysaccharides , can set off B cells without T cell assistance . These cost term T-cell-independent antigens . However , these antigens move B cells to develop solely IgM antibody . The synthesis of other antibody types , such as IgG , IgA , and IgE , necessitates Interleukins 4 and 5 , which are exclusively produced by T helper cell .
5. B Cell Antigen Recognition :B cells employ their surface IgM as an antigen receptor , enabling them to distinguish a plethora of antigens , from protein to lipids and nucleic acids . This broad realization spectrum empowers B cells to generate antibody against a vast array of molecule . However , for protein fragment to live deliver to helper T cell , they must cost associated with category II MHC protein .

Possibility of antibody formation

The genesis of antibodies , essential component of the immune system , have make up a matter of scientific wonder and debate . Over time , two primary theory hold issue to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory posits that an immunocompetent cell inherently possesses the capability to produce a myriad of antibody . The antigen , upon introduction , instructs these cells to yield specific antibody complementary to itself . Two sub-theories further elucidate this conception :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , guiding the formation of the antibody . The result antibody molecule take a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Bring in by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cells , induce a ancestral change . This change involves the integration of the antigenic determinant ’ s genocopy into the genome , which is then passed on to progeny cells . Still , this explanation make lose favor over time .

B . Selective Theories

These theories suggest that the torso already possess a repertoire of potential antibodies , and the introduction of an antigen just selects the appropriate 1 . Three sub-theories further point this conception :

1. Side Chain Theory:
   • Deliver by Ehrlich in 1898 .
   • Argues that immunocompetent cells have show up receptors that can interact with antigen possessing complementary side irons . Upon antigen introduction , these receptors bind with the antigen , becoming inactive . To make up , the cell overproduces similar receptors , which equal then released as antibodies .
2. Theory:
   • Propose by Jerne in 1955 .
   • Indicate that during fetal evolution , the body produces globulin particle against all conceivable antigen . Upon antigen introduction , the antigen selectively binds to the almost complementary globulin molecule , stimulate the production of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduced by Burnet in 1957 .
   • Proposes that during fetal development , a huge array of immunologically competent cell clones , each with a unique antibody pattern , is produce . Each of these cells expresses membrane receptors specific to a particular antigen , determined before the cell ’ s photograph to the antigen . Upon antigen introduction , the cell with the couple receptor is activated , proliferates , and raise the corresponding antibody . This theory , widely accepted today , extend insights into immunological specificity , memory , and the ability to distinguish between self and non-self .

Element affecting product of antibodies

The production of antibody , a pivotal aspect of the immune answer , exist influence by a myriad of factors . Understanding these determinants is essential for both basic immunology and clinical application . Herein , we delve into the substantial element that regulate antibody production :

1. Genetic Factors:
   • The genetic makeup of an order its answer to antigens . Some are responders , give rise antibodies upon exposure , while others , termed nonresponders , serve not .
   • The immune answer ( Ir ) gene , located on the short weapon of chromosome six , governs these version .
2. Years:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , marked by the development of lymphoid organ , equal reach by years 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally strike both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acid and vitamins , can curtail antibody production .
4. Road of Antigen Administration:
   • The way of antigen delivery plays a pivotal part in provoke an immune reply . Parenteral administration typically induce a more robust reception compare to oral or nasal routes .
5. Dose of Antigen:
   • An optimum dosage of antigen is essential for a maximal immune reaction . Extremely high or low dosage can result to immunological paralysis , a state of reduced immune responsiveness .
6. Multiple Antigen:
   • Concurrent administration of multiple antigen can run to varied antibody reaction due to antigenic competition . The exact expression and proportion of these antigens cost essential for attain desired consequence .
7. Adjuvants:
   • Adjuvants exist substance that enhance the immunogenicity of antigens by prolonging antigenic stimulation . Examples include Freund ’ s incomplete and utter adjuvants , aluminum salt , and early substances like silica particles .
8. Immunosuppressive Agents:
   • These agents dampen the immune response and are employ in scenarios like transplantation surgeries . Examples include :
     • X-irradiation: Impedes antibody product place 24 hour of exposure .
     • Radiometric Drugs: Specifically direct B cells , inhibiting their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by regulate interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Mark disseminate lymphocytes , spare those in lymphoid organs .

Monoclonal Antibodies

Monoclonal antibody ( mAbs ) are a category of antibodies infer from a single cell ancestry , see to it their homogeneity . Unlike polyclonal antibody , which be produced by multiple plasma cell clones and be heterologous in nature , monoclonal antibody be specific to a single antigenic determinant .

Origin and Distinction: Monoclonal antibodies originate from conditions like multiple myeloma , where a queer plasma cell clone give rise antibodies against a specific antigenic determinant . This specificity contrasts with polyclonal antibodies , which rise from various plasma cell clones in reply to an antigen .

Product Methodology: The pioneering method for monoclonal antibody production was introduced by Kohler and Milstein in 1975 , bring in them the Nobel Prize in 1984 . Their technique necessitate the creation of hybridomas , which be formed by merge myeloma cells with antibody-producing cell . These hybridomas , once established , can indefinitely produce monoclonal antibodies , proving priceless for inquiry and diagnostic function .

The procedure involves :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ s spleen with mouse myeloma cell that miss the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion utilize agents like polyethylene glycol .
4. Culturing the fused cells in a medium ( HAT media ) that supports hybrid cell increase but inhibit the growth of parent cell .
5. Screening the result cell clones for antibody product against the target antigen .
6. Selecting and perpetually culturing the clones that develop the hope antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody place challenge for therapeutic use in humans . Consequently , advancements led to the evolution of human monoclonal antibodies , include chimeric antibody . These chimeric antibody , compile of human constant regions and mouse varying regions , exist be explored for leukemia treatment . Furthermore , they can live utilize to target tumor cell either by hand over toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Purpose of Antibodies

Antibodies , as well know as immunoglobulins , play a pivotal role in the immune system ’ s defense mechanism against pathogens and their associated production . These Y-shaped protein exist specifically tailored to recognize and neutralize alien invaders , ensure the host ’ sec protection against various infection . Herein , we dig into the multifaceted functions of antibodies :

1. Neutralization: One of the main part of antibodies cost neutralization . By binding directly to pathogens or their toxins , antibodies can inhibit their power to seize to and infect host cell . For example , antibodies specific to bacterial toxins can block the toxin ’ s interaction with horde cell , thereby knock off its harmful effects . Similarly , antibodies can keep viruses or bacteria from initiating infection by hindering their attachment to direct cells .
2. Opsonization: Opsonization cost a process where antibodies coat pathogens , enhancing their realization and uptake by phagocytic cell , such as macrophages and neutrophil . When antibody tie to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can as well activate the complement system , a series of protein that work in tandem to destroy pathogens . Upon stick to to pathogens , sure antibodies can spark the complement cascade , result to the formation of the membrane attack composite ( MAC ) that directly lyses sure bacteria and viruses . Additionally , some by-product of the complement cascade , like C3b , can opsonize pathogens , farther enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological part , antibody serve as crucial tool in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can render insight into the individual ’ sec humoral immunity status . Technique like radial immunodiffusion and immunoelectrophoresis live usually apply to measure these antibody , aid in the diagnosis and monitoring of respective diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the product of antibody by B cells in response to alien antigens . This mechanism hold make up instrumental in oppose against several pathogens throughout history . Here , we illuminate two discrete examples of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical records , include the discovery of smallpox wound on the mummy of Pharaoh Ramses V , propose the ancient prevalence of this deadly disease . Smallpox have catastrophic impacts , in particular decimating indigenous populations in the Americas and Australia . However , by the goal of 1979 , a global vaccination cause successfully eradicated the , score a massive accomplishment in the annals of medicine .

The origin of vaccination can be follow back to Edward Jenner ’ s astute observation regarding the opposition of milkmaids to smallpox during its rampant gap . Prior to Jenner ’ sec work , variolation , a pattern demand the intentional introduction of pus from smallpox victims into sound individuals , was apply as a fundamental figure of inoculation . While the underlie mechanisms of the secondary humoral immune reception be not so far understood , the principle of bring on a mild infection to confer future security exist discern .

Jenner ’ s groundbreaking experiment involve the inoculation of a youthful son with pus deduce from cowpox sores of a milkmaid . Unusually , the boy exhibited immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing weakened or inactivated pathogens , innovative approaches were necessitated due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector strategy . Employ a genetically modified chimpanzee cold virus , know to arouse robust immune response , the vaccine introduces the SARS-CoV-2 spike protein into the human body . This alien protein activate the primary humoral answer , culminating in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines redeem the genetic design for the COVID-19 spike protein right away into cells . The cells then synthesize the spike protein , initiating the humoral immune reaction . Contrary to some misconceptions , mRNA vaccines serve not alter human DNA . Or else , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and directly initiate translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system cost a complex network of cells and proteins that defends the body against pathogens . It can exist broadly categorized into two chief types : humoral immunity and cell-mediated immunity . Each type has distinct characteristics and functions . Here , we define the difference between these two branches of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produced	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Outside or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cells , viruses , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing be require	No ( Unprocessed antigens are realize . )	Yes ( Antigen are first work on and then presented by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( signaling protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells equal chiefly responsible for producing antibodies in the humoral immune response ?
a ) T cells
b ) Macrophages
c ) B cells
d ) Dendritic cell

Show response

Which type of immunity be conferred by the production of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show result

Which of the pursuit live NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show response

The primary immune reception is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the following exist a characteristic of the secondary humoral immune answer ?
a ) Slower onset than the chief reception
b ) Low antibody concentration than the main reaction
100 ) Production of memory B cells
d ) Absence of IgG product

Show result

Which type of cells present antigens to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
c ) Plasma cell
d ) Memory cells

Show answer

Which antibody is chiefly base in mucosal surface and secretion ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the following live NOT a characteristic of monoclonal antibody ?
a ) Raise by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Use in diagnostic and therapeutic application

Show response

The process by which antibody enhance the phagocytosis of pathogens is call :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the pursuit live the primary occasion of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
c ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cells
d ) Bring on direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA manner : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Antigen Encounter and Processing :Upon the initial impinging with a alien pathogen , antigen-presenting cell ( APCs ) capture and internalize the antigen . These APCs then bear the antigen , convince specific fragment into major histocompatibility complex class II ( ) surface proteins .
2. T Helper Cell Activation :The MHC II surface protein , now presenting the antigen fragments , are recognized by T helper cell . This recognition is a essential measure , as it ensures that the immune system react specifically to the foreign antigen .
3. Cytokine Production :Upon recognize the MHC II-antigen complex , T helper cell grow cytokines , signaling molecules that meet a critical role in regulate the immune reply .
4. B Cell Activation and Differentiation :Influenced by the cytokines relinquish by T assistant cell , naïve B cell become activated . Once activated , these B cell undergo differentiation , pay rise to two primary cell types : plasma cell and memory B cell .
5. Antibody Product :The newly organize plasma cell venture on their primary occasion : the production and secretion of antibody . Initially , IgM antibodies are produced . Still , if the pathogen persists still after peak IgM secretion , the immune system may as well produce IgG or IgA antibodies to bolster the defense .
6. Temporal Dynamics :The primary phase equal not instantaneous . Following the initial exposure to an antigen , there ’ sec a lag period , typically ranging from 7 to 10 day , before peak antibody levels cost arrive at in the serum . This lag can change based on the nature of the antigen ; for example , certain antigens might get a response within hours , while others might take weeks . Factors influencing this period include the antigen ’ sec dose , its mode of delivery ( oral or parenteral ) , and its inherent properties .
7. Antibody Dynamics :During this chief response , the concentration of antibodies in the serum rises for respective weeks before step by step declining . While IgM levels lean to wane more rapidly , IgG levels hang on for a more prolonged period , extend sustained protection .

In summary , the primary stage of the humoral immune response is a meticulously orchestrated series of case that check the torso mounts an effective defense against novel pathogens . This phase put the foundation for subsequent immune responses , check that the body is good train for future skirmish with the same antigen .

Secondary Phase/Secondary humoral immune response

The secondary humoral immune response , also refer to as the anamnestic or memory reception , present the immune system ’ s enhanced response to a previously encountered pathogen . This heightened reaction cost facilitate by memory B cells , which are generated during the principal photograph to the antigen and can persist for prolonged durations , ranging from weeks to year .

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly discern the antigenic determinants of the microorganism . Their former skirmish with the antigen equips them with a heightened province of readiness , enabling a rapid and efficient response .
2. Clonal Expansion and Differentiation :Upon antigen realization , memory B cells undergo clonal expansion , give rise a big number of highly-specific plasma cells . These plasma cell are tailor to produce antibody that specifically direct the encountered antigen .
3. Enhanced Antibody Production :In the secondary answer , there equal a marked increase in the product of antibody , surpassing the level observed during the main reception by over a thousand-fold . While IgG is the predominant immunoglobulin produced , there live as well a notable production of IgM , IgA , and IgE .
4. Rapid Peak Reception :One of the trademark of the secondary humoral immune answer cost the swift attainment of peak antibody degree , typically within a mere 3 to 5 day post-exposure . This contrasts with the long lag period observe during the principal reply .
5. Persistency of Memory Cells :The enhanced and rapid secondary reply can equal ascribe to the presence of antigen-specific memory cell , which persist post the initial antigen skirmish . These cells undergo extensive proliferation , generate a vast array of specific B cell and plasma cell that mediate the secondary response .
6. Qualitative Difference in Antibody Production :While the measure of IgM produced during the secondary reply is like to that of the primary reaction , there is a significant increase in the production of IgG . Moreover , the raise IgG persists for a more lengthy period during the secondary reaction .
7. Enhanced Antibody Affinity :Antibody produced during the secondary response exhibit a higher affinity for the antigen , think of they bind more tightly and are less probable to divorce . This increase binding intensity arises from somatic hypermutation , a procedure where changes happen in the DNA encoding the antigen-binding site , optimizing antibody-antigen interaction .

Luck of Antigen in Tissues

The luck of an antigen within the torso is mostly determine by its mode of introduction . This trajectory and eventual localization of the antigen bring a pivotal office in influence the immune response .

1. Subcutaneous Organization :When antigens are introduced subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which run out the interstitial fluid from , capture these antigen and transports them to the lymph nodes . Hither , specialize immune cell can recognize , process , and lead up an immune response against these antigens . Solely a minuscule fraction of the antigen reaches the spleen , a secondary lymphoid organ , when introduced via this road .
2. Intravenous Organization :Intravenous pitch of antigens paints a different movie . Such antigens exist mainly see in systemic organ like the spleen , liver , bone marrow , kidneys , and lungs . The direct entrance into the bloodstream allows these antigen to disseminate widely and interact with various tissues . Interestingly , despite the extensive vascular network connect them , lymph nodes exhibit minimum presence of these intravenously introduced antigens .
3. Antigen Clearance :A significant portion of the antigens , no matter of their route of entry , undergo degradation . Reticuloepithelial cell , which form part of the torso ’ s mononuclear phagocyte system , play a essential part in this procedure . They engulf and break down these antigen , see to it that the body is not overwhelmed . Post degradation , around three-quarters of these antigens are excreted via the urine , in effect get rid of them from the body .

Product of Antibody

The intricate process of antibody synthesis live a testament to the body ’ sec organize defense mechanism . This synthesis live orchestrated through the collaborative efforts of three primary cell types : macrophages , T helper cells , and B cells .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cell , classified as APCs , cost pivotal in presenting antigen to immunocompetent cells . For many T-cell-dependent antigen , include protein and red blood cell , macrophages are essential for processing the antigen before antibody production can commence . However , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cell expose the antigen on their surface , either in its native form or as processed fragments .
2. Macrophages and Optimal Antigen Photo :Macrophages play a nuanced purpose in regulate the antigen dosage exposed to lymphocytes , see to it the optimal activation of immunological reaction . Following macrophage processing , antigen fragments , in conjunction with class II MHC protein , surface on the macrophages . This complex then employ specific receptors on helper T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein composite , helper T cells release cytokines . These cytokines , include Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cell to raise antigen-specific antibody . The B cells , once activated , undergo clonal proliferation , differentiate into plasma cell . These plasma cells are the factories develop specific immunoglobulins or antibodies , which play role such as neutralize toxins and virus and facilitate pathogen uptake by phagocytic cell .
4. T-cell-independent Antigens :While helper T cells live indispensable for most antibody productions , sure chemical , like polysaccharides , can touch off B cell without T cell assistance . These are termed T-cell-independent antigens . However , these antigens prompt B cell to produce solely IgM antibody . The synthesis of other antibody type , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which are exclusively give rise by T help cells .
5. B Cell Antigen Recognition :B cell utilize their surface IgM as an antigen receptor , enabling them to make out a plethora of antigens , from protein to lipids and nucleic acids . This liberal realization spectrum empowers B cell to yield antibodies against a vast array of molecules . However , for protein fragments to equal presented to helper T cells , they must equal associated with class II MHC protein .

Theories of antibody formation

The genesis of antibodies , essential constituent of the immune system , has been a topic of scientific curiosity and debate . Over time , two primary theories have issue to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory posits that an immunocompetent cell inherently possess the capability to produce a myriad of antibodies . The antigen , upon introduction , instructs these cell to yield specific antibody complementary to itself . Two sub-theories further elucidate this concept :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Suggest that the antigen or its determinants number as a template , guiding the formation of the antibody . The resulting antibody particle take a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cell , induce a hereditary change . This change involve the integration of the antigenic determinant ’ sec genocopy into the genome , which is then spend on to progeny cell . Still , this explanation has lost favor over time .

B . Selective Theories

These possibility suggest that the torso already possess a repertoire of possible antibodies , and the introduction of an antigen merely choose the appropriate ace . Three sub-theories further point this concept :

1. Slope Chain Theory:
   • Deliver by Ehrlich in 1898 .
   • Argues that immunocompetent cell have surface receptors that can interact with antigens possessing complementary side irons . Upon antigen introduction , these receptors tie with the antigen , becoming motionless . To compensate , the cell overproduces similar receptors , which be then issue as antibodies .
2. Theory:
   • Suggest by Jerne in 1955 .
   • Propose that during fetal evolution , the body produces globulin molecules against all conceivable antigen . Upon antigen introduction , the antigen selectively stick to to the almost complementary globulin particle , stimulating the product of the corresponding antibody .
3. Clonal Selection Theory:
   • Bring in by Burnet in 1957 .
   • Proposes that during fetal evolution , a immense array of immunologically competent cell clones , each with a unique antibody pattern , exist develop . Each of these cell convey membrane receptors specific to a peculiar antigen , find out before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the matching receptor is set off , proliferates , and develop the corresponding antibody . This theory , widely accepted today , bid insight into immunological specificity , memory , and the power to recognize between self and non-self .

Factors affecting product of antibody

The production of antibody , a pivotal aspect of the immune response , is influenced by a myriad of component . Understand these determinants is essential for both basic immunology and clinical applications . Herein , we dig into the substantial element that regulate antibody product :

1. Genetic Component:
   • The genetic makeup of an prescribe its response to antigen . Some exist responders , produce antibodies upon exposure , while others , termed nonresponders , do not .
   • The immune reception ( Ir ) gene , settle on the short arm of chromosome six , governs these version .
2. Years:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , note by the growing of lymphoid organs , is attain by ages 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acids and vitamins , can restrict antibody product .
4. Route of Antigen Administration:
   • The style of antigen delivery plays a pivotal use in eliciting an immune reaction . Parenteral establishment typically bring on a more robust reply equate to oral or nasal routes .
5. Dose of Antigen:
   • An optimum dosage of antigen live essential for a maximum immune reply . Extremely high or low doses can lead to immunological paralysis , a state of shorten immune responsiveness .
6. Multiple Antigens:
   • Concurrent establishment of multiple antigen can head to vary antibody responses due to antigenic competition . The exact formulation and proportion of these antigens live crucial for achieving desired result .
7. Adjuvants:
   • Adjuvants are substance that enhance the immunogenicity of antigen by sustain antigenic stimulus . Examples include Freund ’ s incomplete and complete adjuvants , aluminum salt , and early substances like silica particle .
8. Immunosuppressive Agent:
   • These agent moisten the immune reply and live utilize in scenarios like transplantation surgeries . Example include :
     • X-irradiation: Impedes antibody product post 24 hour of exposure .
     • Radiometric Drugs: Specifically direct B cells , inhibiting their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtail cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Mark circulating lymphocytes , sparing those in lymphoid organs .

Monoclonal Antibodies

Monoclonal antibody ( mAbs ) are a class of antibodies derived from a single cell lineage , ensuring their homogeneity . Unlike polyclonal antibody , which be develop by multiple plasma cell clones and exist heterologous in nature , monoclonal antibodies equal specific to a single antigenic determinant .

Ancestry and Distinction: Monoclonal antibody develop from circumstance like multiple myeloma , where a singular plasma cell clone develop antibodies against a specific antigenic determinant . This specificity contrasts with polyclonal antibodies , which rise from several plasma cell clones in answer to an antigen .

Product Methodology: The pioneering method for monoclonal antibody product live introduced by Kohler and Milstein in 1975 , bring in them the Nobel Prize in 1984 . Their technique involved the creation of hybridomas , which be formed by mix myeloma cell with antibody-producing cell . These hybridomas , once demonstrate , can indefinitely make monoclonal antibodies , proving priceless for research and diagnostic purposes .

The process demand :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ sec spleen with mouse myeloma cell that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion employ agents like polyethylene glycol .
4. Culturing the fused cells in a medium ( HAT medium ) that supports hybrid cell growing but conquer the growth of parent cell .
5. Shield the resulting cell clones for antibody production against the target antigen .
6. Selecting and perpetually culturing the clones that produce the want antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody lay challenges for therapeutic use in humans . Accordingly , advancements led to the evolution of human monoclonal antibody , including chimeric antibodies . These chimeric antibodies , compile of human constant part and mouse varying region , cost exist explored for leukemia treatment . Furthermore , they can be employed to target tumor cell either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Office of Antibodies

Antibody , also known as immunoglobulins , play a pivotal purpose in the immune system ’ sec defense mechanism against pathogens and their associated products . These Y-shaped proteins are specifically tailored to discern and knock off foreign invaders , see to it the host ’ sec protection against various infection . Herein , we dig into the multifaceted purpose of antibodies :

1. Neutralization: One of the primary role of antibodies live neutralization . By binding right away to pathogens or their toxins , antibody can conquer their power to seize to and infect horde cells . For instance , antibodies specific to bacterial toxins can block the toxin ’ s interaction with host cell , thereby knock off its harmful impression . Likewise , antibodies can forestall viruses or bacteria from initiating infections by hindering their attachment to target cell .
2. Opsonization: Opsonization equal a procedure where antibody coat pathogens , enhancing their recognition and uptake by phagocytic cells , such as macrophages and neutrophil . When antibodies bind to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can also activate the complement system , a series of proteins that work in tandem to destroy pathogens . Upon binding to pathogens , sure antibody can spark the complement cascade , result to the formation of the membrane approach composite ( MAC ) that directly lyses certain bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , farther enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological purpose , antibody do as essential tools in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can supply insights into the individual ’ sec humoral immunity status . Technique like radial immunodiffusion and immunoelectrophoresis live commonly employed to evaluate these antibodies , aiding in the diagnosis and monitoring of respective disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibody by B cells in reaction to alien antigen . This mechanism make make up instrumental in defending against several pathogens throughout account . Hither , we elucidate two distinct examples of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox lesions on the mummy of Pharaoh Ramses V , advise the ancient prevalence of this deadly disease . Smallpox hold catastrophic impacts , particularly decimating indigenous population in the Americas and Australia . Still , by the goal of 1979 , a global vaccination campaign successfully eradicated the , marking a monumental achievement in the annals of medicine .

The origin of vaccination can be draw back to Edward Jenner ’ s sharp observation consider the resistance of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ s work , variolation , a pattern demand the intentional introduction of pus from smallpox victim into sound individual , equal employed as a fundamental form of inoculation . While the underlying mechanism of the secondary humoral immune response were not still understood , the rationale of stimulate a meek infection to bestow next security was recognized .

Jenner ’ s groundbreaking experiment necessitate the inoculation of a young boy with pus derived from cowpox sores of a milkmaid . Remarkably , the boy exhibited immunity to subsequent smallpox photo , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines employing weakened or inactivated pathogens , innovative approaches were necessitated due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector strategy . Utilizing a genetically modified chimpanzee cold virus , know to elicit robust immune responses , the vaccine introduce the SARS-CoV-2 spike protein into the human body . This foreign protein set off the primary humoral response , culminating in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines deliver the genetic blueprint for the COVID-19 spike protein immediately into cells . The cell then synthesize the spike protein , initiating the humoral immune reply . Contrary to some misconceptions , mRNA vaccines serve not vary human DNA . Instead , they harness the cellular machinery for protein synthesis , bypassing the transcription stage and directly initiating translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system live a complex network of cell and proteins that defends the torso against pathogens . It can cost broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and functions . Here , we delineate the difference between these two branches of the immune reception .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody raise	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stand for membranous .	TCR receptors
Accessory receptors call for	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing equal needed	No ( Unprocessed antigen live recognized . )	Yes ( Antigens are first work on and then presented by MHC of antigen-presenting cells )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells cost chiefly responsible for develop antibodies in the humoral immune response ?
a ) T cells
b ) Macrophages
c ) B cells
d ) Dendritic cell

Show answer

Which type of immunity is bestow by the production of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show answer

Which of the pursuit is NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show answer

The main immune response is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show solution

Which of the pursuit be a characteristic of the secondary humoral immune response ?
a ) Slower onset than the principal answer
b ) Humble antibody concentration than the main response
100 ) Product of memory B cell
d ) Absence of IgG production

Show answer

Which type of cells present antigens to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cells ( APCs )
c ) Plasma cells
d ) Memory cell

Show solution

Which antibody is mainly find in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit is NOT a characteristic of monoclonal antibodies ?
a ) Give rise by a single clone of cells
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show response

The process by which antibodies enhance the phagocytosis of pathogens is predict :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the pursuit live the chief function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
100 ) Facilitating phagocytosis by stick to to Fc receptors on phagocytic cells
d ) Cause direct cell lysis

Show response

FAQ

Address

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Activation of Memory B Cells :Upon re-exposure to the same antigen , memory B cell swiftly recognize the antigenic determinants of the microorganism . Their previous encounter with the antigen equip them with a heightened nation of readiness , enable a rapid and effective response .
2. Clonal Expansion and Differentiation :Upon antigen recognition , memory B cell undergo clonal expansion , develop a big number of highly-specific plasma cell . These plasma cell are tailored to give rise antibody that specifically direct the encountered antigen .
3. Enhanced Antibody Product :In the secondary answer , there exist a marked increase in the production of antibody , pass by the point notice during the main response by over a thousand-fold . While IgG cost the predominant immunoglobulin produced , there live too a famed product of IgM , IgA , and IgE .
4. Rapid Peak Reception :One of the hallmarks of the secondary humoral immune reply is the swift attainment of peak antibody levels , typically within a simple 3 to 5 day post-exposure . This contrast with the long lag period observed during the primary reply .
5. Persistence of Memory Cells :The enhanced and rapid secondary reply can exist attributed to the presence of antigen-specific memory cells , which remain post the initial antigen encounter . These cells undergo extensive proliferation , generate a vast array of specific B cells and plasma cell that mediate the secondary answer .
6. Qualitative Difference in Antibody Product :While the quantity of IgM produced during the secondary response cost similar to that of the principal reply , there is a significant increase in the product of IgG . Furthermore , the give rise IgG persists for a more extensive period during the secondary response .
7. Enhanced Antibody Affinity :Antibodies give rise during the secondary reaction exhibit a high affinity for the antigen , entail they tie more tightly and are less likely to dissociate . This increase binding force arises from somatic hypermutation , a procedure where change occur in the DNA encoding the antigen-binding site , optimizing antibody-antigen interactions .

Fate of Antigen in Tissues

The destiny of an antigen within the torso is largely determined by its mode of introduction . This trajectory and eventual localization of the antigen play a pivotal role in shaping the immune response .

1. Subcutaneous Administration :When antigens are introduce subcutaneously , they predominantly localize in the draining lymph nodes . The lymphatic system , which run out the interstitial fluid from , capture these antigens and transports them to the lymph nodes . Hither , specialized immune cell can recognize , process , and originate an immune reply against these antigen . Only a minuscule fraction of the antigen achieve the spleen , a secondary lymphoid organ , when bring in via this road .
2. Intravenous Establishment :Intravenous delivery of antigens paints a different picture . Such antigens are mainly find in systemic organs like the spleen , liver , bone center , kidney , and lung . The direct entry into the bloodstream let these antigen to disseminate widely and interact with various tissue . Interestingly , despite the extensive vascular network associate them , lymph nodes exhibit minimal presence of these intravenously bring in antigen .
3. Antigen Clearance :A important share of the antigens , regardless of their path of debut , undergo degradation . Reticuloepithelial cell , which make region of the body ’ s mononuclear phagocyte system , play a crucial role in this procedure . They engulf and break down these antigen , ensuring that the body equal not overwhelmed . Post degradation , around three-quarters of these antigen are excreted via the urine , effectively eliminating them from the body .

Production of Antibodies

The intricate procedure of antibody synthesis exist a testament to the torso ’ s coordinate defense mechanism . This synthesis equal orchestrated through the collaborative efforts of three primary cell type : macrophages , T helper cells , and B cell .

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , separate as APCs , are pivotal in confront antigen to immunocompetent cells . For many T-cell-dependent antigens , including protein and erythrocytes , macrophages are essential for work on the antigen before antibody product can set out . Still , T-cell-independent antigens bypass this macrophage processing . Post-processing , macrophages and dendritic cells expose the antigen on their surface , either in its native form or as processed fragment .
2. Macrophages and Optimal Antigen Photo :Macrophages play a nuanced use in regulate the antigen dosage display to lymphocytes , ensuring the optimum activation of immunological responses . Pursue macrophage processing , antigen fragment , in conjunction with class II MHC protein , surface on the macrophages . This complex then engages specific receptors on assistant T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein complex , helper T cell release cytokines . These cytokines , include Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cells to raise antigen-specific antibody . The B cell , once activated , undergo clonal proliferation , differentiating into plasma cell . These plasma cell exist the factories producing specific immunoglobulins or antibodies , which act role such as neutralizing toxins and viruses and facilitating pathogen uptake by phagocytic cell .
4. T-cell-independent Antigen :While helper T cell are indispensable for most antibody productions , certain chemicals , like polysaccharides , can activate B cell without T cell assistance . These are termed T-cell-independent antigens . However , these antigens motivate B cells to grow only IgM antibody . The synthesis of other antibody types , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which be exclusively give rise by T helper cells .
5. B Cell Antigen Recognition :B cell employ their surface IgM as an antigen receptor , enabling them to realize a plethora of antigen , from proteins to lipids and nucleic acids . This broad recognition spectrum empowers B cells to yield antibodies against a vast array of molecule . However , for protein fragments to exist deliver to helper T cell , they must exist associated with class II MHC proteins .

Theory of antibody formation

The genesis of antibody , essential portion of the immune system , have been a theme of scientific wonder and debate . Over time , two primary possibility have emerged to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory submit that an immunocompetent cell inherently possesses the capacity to develop a myriad of antibody . The antigen , upon introduction , instruct these cell to yield specific antibody complementary to itself . Two sub-theories further elucidate this concept :

1. Direct Template Theory:
   • Propose by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , take the formation of the antibody . The result antibody molecule adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon go into antibody-producing cells , bring on a hereditary change . This change require the integration of the antigenic determinant ’ s genocopy into the genome , which is then die on to progeny cell . However , this explanation make miss favor over time .

B . Selective Theory

These theory suggest that the torso already possesses a repertoire of potential antibodies , and the introduction of an antigen simply selects the appropriate one . Three sub-theories further detail this concept :

1. Slope Chain Theory:
   • Deliver by Ehrlich in 1898 .
   • Argues that immunocompetent cell have surface receptors that can interact with antigen possessing complementary slope irons . Upon antigen introduction , these receptors tie with the antigen , becoming still . To compensate , the cell overproduces like receptors , which exist then released as antibodies .
2. Theory:
   • Propose by Jerne in 1955 .
   • Suggests that during fetal evolution , the torso produces globulin molecule against all conceivable antigens . Upon antigen introduction , the antigen selectively tie up to the most complementary globulin molecule , stimulate the production of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduce by Burnet in 1957 .
   • Proposes that during fetal development , a immense array of immunologically competent cell clones , each with a unique antibody form , exist give rise . Each of these cell expresses membrane receptors specific to a special antigen , determined before the cell ’ s photograph to the antigen . Upon antigen introduction , the cell with the cope with receptor exist trigger , proliferates , and produce the corresponding antibody . This theory , widely accepted today , extend insight into immunological specificity , memory , and the power to distinguish between self and non-self .

Factors pretend production of antibodies

The production of antibodies , a pivotal facet of the immune reaction , is determine by a myriad of factors . Understand these determinants is essential for both basic immunology and clinical applications . Herein , we dig into the significant factors that modulate antibody production :

1. Genetic Component:
   • The genetic makeup of an dictates its response to antigens . Some are responders , give rise antibody upon photograph , while others , term nonresponders , do not .
   • The immune response ( Ir ) gene , place on the short arm of chromosome six , governs these version .
2. Years:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , marked by the maturation of lymphoid organs , is achieved by years 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acids and vitamin , can curtail antibody product .
4. Route of Antigen Administration:
   • The fashion of antigen delivery meet a pivotal use in provoke an immune response . Parenteral administration typically have a more robust response compared to oral or nasal routes .
5. Dose of Antigen:
   • An optimum dose of antigen live essential for a maximal immune reaction . Extremely high or low doses can result to immunological paralysis , a province of cut down immune responsiveness .
6. Multiple Antigen:
   • Concurrent administration of multiple antigens can lead to depart antibody response due to antigenic competition . The exact preparation and proportion of these antigens exist essential for achieving desired outcomes .
7. Adjuvants:
   • Adjuvants are substances that enhance the immunogenicity of antigens by prolonging antigenic stimulation . Examples include Freund ’ s incomplete and utter adjuvants , aluminum salt , and other meaning like silica particle .
8. Immunosuppressive Agent:
   • These agent moisten the immune reception and are utilize in scenarios like transplantation surgeries . Examples include :
     • X-irradiation: Impedes antibody product place 24 hours of photograph .
     • Radiometric Drugs: Specifically target B cell , conquer their replication .
     • Corticosteroids: Lessen the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , restrict cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Objective disseminate lymphocytes , sparing those in lymphoid organs .

Monoclonal Antibody

Monoclonal antibody ( mAbs ) are a grade of antibody descend from a single cell ancestry , ensuring their homogeneity . Unlike polyclonal antibody , which are produced by multiple plasma cell clones and cost heterologous in nature , monoclonal antibodies are specific to a single antigenic determinant .

Origin and Distinction: Monoclonal antibody originate from conditions like multiple myeloma , where a remarkable plasma cell clone produces antibodies against a specific antigenic determinant . This specificity contrasts with polyclonal antibodies , which get up from several plasma cell clones in response to an antigen .

Product Methodology: The pioneering method for monoclonal antibody product live introduced by Kohler and Milstein in 1975 , make them the Nobel Prize in 1984 . Their technique call for the creation of hybridomas , which are make by fusing myeloma cell with antibody-producing cells . These hybridomas , once established , can indefinitely raise monoclonal antibody , show invaluable for inquiry and diagnostic intention .

The process call for :

1. Inoculating an beast , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ sec spleen with mouse myeloma cells that miss the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion using agents like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT medium ) that support hybrid cell growth but inhibits the growth of parent cells .
5. Shield the result cell clones for antibody product against the prey antigen .
6. Selecting and perpetually culturing the clones that produce the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody posed challenges for therapeutic habit in humans . Accordingly , advancements led to the development of human monoclonal antibodies , include chimeric antibody . These chimeric antibody , composed of human constant regions and mouse variable regions , exist being explored for leukemia discussion . Moreover , they can live employed to target tumor cell either by hand over toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Affair of Antibody

Antibody , too know as immunoglobulins , play a pivotal role in the immune system ’ s defense mechanisms against pathogens and their associated products . These Y-shaped proteins are specifically tailored to recognize and knock off alien invaders , ensuring the host ’ s protection against respective infections . Herein , we delve into the multifaceted affair of antibodies :

1. Neutralization: One of the primary roles of antibody is neutralization . By binding straight to pathogens or their toxins , antibodies can inhibit their power to attach to and infect host cells . For instance , antibody specific to bacterial toxins can block the toxin ’ s interaction with horde cells , thereby neutralizing its harmful effects . Likewise , antibodies can prevent viruses or bacteria from initiating infection by hinder their attachment to target cell .
2. Opsonization: Opsonization be a process where antibodies coat pathogens , enhancing their recognition and intake by phagocytic cells , such as macrophages and neutrophils . When antibodies tie to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can as well trigger the complement system , a series of proteins that bring in tandem to ruin pathogens . Upon binding to pathogens , sure antibody can set off the complement cascade , leading to the formation of the membrane approach complex ( MAC ) that right away lyses sure bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , further enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological part , antibody serve as essential tools in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insight into the individual ’ sec humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis exist ordinarily employed to measure these antibodies , aid in the diagnosis and monitoring of several disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibodies by B cell in response to alien antigen . This mechanism own exist instrumental in defending against various pathogens throughout history . Hither , we clarify two distinct model of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox lesions on the ma of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impacts , especially decimating indigenous population in the Americas and Australia . Still , by the goal of 1979 , a global vaccination campaign successfully eradicated the , mark a monumental achievement in the annals of medicine .

The origins of vaccination can equal traced back to Edward Jenner ’ s sharp observation consider the resistance of milkmaids to smallpox during its rampant gap . Prior to Jenner ’ s work , variolation , a practice involving the intentional introduction of pus from smallpox victim into sound individuals , exist employed as a rudimentary form of inoculation . While the underlie mechanisms of the secondary humoral immune response were not yet understood , the principle of induce a mild infection to confer future protection was recognized .

Jenner ’ s groundbreaking experiment involve the inoculation of a young son with pus derived from cowpox sores of a milkmaid . Remarkably , the boy exhibit immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge set by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines utilize weaken or inactivated pathogens , innovative approach were necessitated due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector strategy . Utilizing a genetically modify chimpanzee cold virus , know to elicit robust immune response , the vaccine introduces the SARS-CoV-2 spike protein into the human body . This foreign protein triggers the primary humoral response , culminating in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines rescue the genetic design for the COVID-19 spike protein directly into cells . The cell then synthesize the spike protein , originate the humoral immune response . Contrary to some misconceptions , mRNA vaccines do not change human DNA . Or else , they harness the cellular machinery for protein synthesis , bypassing the transcription stage and directly initiating translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system equal a complex network of cells and proteins that oppose the body against pathogens . It can equal broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type get distinct characteristics and affair . Hither , we define the differences between these two branch of the immune reply .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies produce	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ tolerate for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigen live recognized . )	Yes ( Antigens are first work on and then presented by MHC of antigen-presenting cell )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( indicate protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells equal primarily responsible for producing antibody in the humoral immune reply ?
a ) T cell
b ) Macrophages
100 ) B cells
d ) Dendritic cell

Show answer

Which type of immunity cost bestow by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show solution

Which of the pursuit is NOT a occasion of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show solution

The chief immune response is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit is a characteristic of the secondary humoral immune response ?
a ) Slower onset than the chief response
b ) Lower antibody concentration than the chief reply
100 ) Product of memory B cells
d ) Absence of IgG production

Show reply

Which type of cells present antigens to immunocompetent cells ?
a ) T cells
b ) Antigen-presenting cells ( APCs )
c ) Plasma cell
d ) Memory cell

Show solution

Which antibody is primarily base in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show response

Which of the following is NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Utilize in diagnostic and therapeutic application

Show solution

The procedure by which antibodies enhance the phagocytosis of pathogens is called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show solution

Which of the following live the main purpose of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
100 ) Facilitating phagocytosis by tie up to Fc receptors on phagocytic cells
d ) Inducing direct cell lysis

Show result

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Role of Antigen-Presenting Cells ( APCs ) :Macrophages and dendritic cells , classify as APCs , exist pivotal in demonstrate antigens to immunocompetent cell . For many T-cell-dependent antigens , include proteins and erythrocytes , macrophages are essential for work on the antigen before antibody product can embark on . However , T-cell-independent antigen bypass this macrophage processing . Post-processing , macrophages and dendritic cell present the antigen on their surface , either in its native kind or as processed fragment .
2. Macrophages and Optimal Antigen Photograph :Macrophages bring a nuanced use in regulate the antigen dosage display to lymphocytes , ensuring the optimum activation of immunological responses . Succeed macrophage processing , antigen fragments , in conjunction with class II MHC proteins , surface on the macrophages . This complex then engage specific receptors on assistant T cells .
3. T Cell Activation and B Cell Stimulation :Upon interaction with the antigen-class II MHC protein composite , helper T cell release cytokines . These cytokines , include Interleukin-2 , Interleukin-4 , and Interleukin-5 , stimulate B cell to develop antigen-specific antibody . The B cell , once activate , undergo clonal proliferation , differentiate into plasma cell . These plasma cells are the factories produce specific immunoglobulins or antibodies , which work part such as knock off toxins and viruses and facilitating pathogen uptake by phagocytic cells .
4. T-cell-independent Antigen :While helper T cells are indispensable for most antibody productions , certain chemical , like polysaccharides , can activate B cell without T cell assistance . These are term T-cell-independent antigens . Even so , these antigen remind B cells to grow only IgM antibodies . The synthesis of other antibody types , such as IgG , IgA , and IgE , necessitate Interleukins 4 and 5 , which cost exclusively develop by T assistant cell .
5. B Cell Antigen Recognition :B cell apply their surface IgM as an antigen receptor , enabling them to distinguish a plethora of antigen , from proteins to lipids and nucleic acid . This broad realization spectrum empowers B cell to yield antibody against a huge array of particle . Still , for protein fragments to be presented to helper T cells , they must be associated with class II MHC protein .

Theory of antibody formation

The genesis of antibodies , essential components of the immune system , has exist a subject of scientific wonder and debate . Over time , two primary theory have emerge to explain the mechanism of antibody formation : the instructive theory and the selective theory .

A . Instructive Theory

This theory submit that an immunocompetent cell inherently possesses the capability to produce a myriad of antibodies . The antigen , upon introduction , instructs these cells to generate specific antibodies complementary to itself . Two sub-theories further elucidate this conception :

1. Direct Template Theory:
   • Advise by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , guiding the formation of the antibody . The resulting antibody particle follow a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cell , induce a hereditary change . This change demand the integration of the antigenic determinant ’ sec genocopy into the genome , which cost then occur on to progeny cell . Still , this explanation has lost favor over time .

B . Selective Possibility

These theory propose that the torso already possess a repertoire of possible antibodies , and the introduction of an antigen merely pick out the appropriate one . Three sub-theories further item this concept :

1. Slope Chain Theory:
   • Present by Ehrlich in 1898 .
   • Argues that immunocompetent cell get surface receptors that can interact with antigen possessing complementary side chain . Upon antigen introduction , these receptors tie up with the antigen , becoming motionless . To make up , the cell overproduces like receptors , which are then issue as antibody .
2. Theory:
   • Proposed by Jerne in 1955 .
   • Suggest that during fetal development , the torso develop globulin particle against all conceivable antigens . Upon antigen introduction , the antigen selectively binds to the most complementary globulin particle , stimulate the production of the corresponding antibody .
3. Clonal Selection Theory:
   • Bring in by Burnet in 1957 .
   • Proposes that during fetal development , a vast array of immunologically competent cell clones , each with a unique antibody practice , cost produced . Each of these cell convey membrane receptors specific to a peculiar antigen , determine before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the cope with receptor is set off , proliferates , and raise the corresponding antibody . This theory , widely accepted today , put up insight into immunological specificity , memory , and the power to distinguish between self and non-self .

Element affecting product of antibody

The product of antibodies , a pivotal aspect of the immune reaction , live influenced by a myriad of factors . Understand these determinants cost crucial for both basic immunology and clinical application . Herein , we dig into the important factors that modulate antibody product :

1. Genetic Factors:
   • The genetic makeup of an dictate its response to antigen . Some exist responders , produce antibodies upon photograph , while others , term nonresponders , do not .
   • The immune response ( Ir ) gene , place on the short arm of chromosome six , rule these variations .
2. Age:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , marked by the growing of lymphoid organs , cost achieved by age 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affect both humoral and cell-mediated immunity .
   • Specific deficiencies , such as those of amino acids and vitamin , can restrict antibody product .
4. Route of Antigen Administration:
   • The mode of antigen delivery plays a pivotal role in eliciting an immune response . Parenteral administration typically induce a more robust answer compare to oral or nasal path .
5. Dose of Antigen:
   • An optimum dose of antigen is essential for a maximum immune reaction . Extremely high or humble doses can take to immunological paralysis , a state of reduce immune responsiveness .
6. Multiple Antigen:
   • Simultaneous administration of multiple antigen can lead to varied antibody answer due to antigenic competitor . The exact expression and proportion of these antigens are essential for achieving desired consequence .
7. Adjuvants:
   • Adjuvants are content that enhance the immunogenicity of antigens by sustain antigenic stimulation . Examples include Freund ’ s incomplete and all over adjuvants , aluminum salt , and other substances like silica particles .
8. Immunosuppressive Agents:
   • These agents dampen the immune response and are apply in scenarios like transplantation surgeries . Model include :
     • X-irradiation: Impedes antibody product place 24 hours of exposure .
     • Radiometric Drugs: Specifically target B cells , conquer their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by regulate interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtail cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets circulating lymphocytes , sparing those in lymphoid organs .

Monoclonal Antibodies

Monoclonal antibodies ( mAbs ) exist a class of antibody derived from a single cell ancestry , ensuring their homogeneity . Unlike polyclonal antibody , which are raise by multiple plasma cell clones and be heterologous in nature , monoclonal antibody are specific to a single antigenic determinant .

Ancestry and Distinction: Monoclonal antibody initiate from circumstance like multiple myeloma , where a remarkable plasma cell clone develop antibodies against a specific antigenic determinant . This specificity contrast with polyclonal antibody , which develop from respective plasma cell clones in reaction to an antigen .

Production Methodology: The pioneering method for monoclonal antibody product exist introduced by Kohler and Milstein in 1975 , earn them the Nobel Prize in 1984 . Their technique involved the world of hybridomas , which are make by fusing myeloma cell with antibody-producing cell . These hybridomas , once established , can indefinitely make monoclonal antibodies , proving priceless for research and diagnostic purposes .

The process involves :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ s spleen with mouse myeloma cells that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion using agents like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT media ) that support hybrid cell increase but inhibits the growth of parent cells .
5. Screening the resulting cell clones for antibody production against the aim antigen .
6. Choose and perpetually culturing the clones that produce the hope antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies posed challenges for therapeutic use in man . Consequently , advancements led to the development of human monoclonal antibodies , including chimeric antibodies . These chimeric antibodies , compose of human constant part and mouse variable area , be live explored for leukemia treatment . Moreover , they can cost employ to target tumor cell either by hand over toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibody

Antibody , too known as immunoglobulins , play a pivotal role in the immune system ’ s defense mechanism against pathogens and their associated products . These Y-shaped protein equal specifically tailor to distinguish and neutralize foreign invaders , ensuring the horde ’ sec security against various infections . Herein , we dig into the multifaceted functions of antibodies :

1. Neutralization: One of the main roles of antibodies is neutralization . By stick to directly to pathogens or their toxins , antibodies can inhibit their ability to bind to and infect host cell . For instance , antibody specific to bacterial toxins can block the toxin ’ s interaction with host cells , thereby neutralize its harmful effects . Similarly , antibodies can prevent viruses or bacteria from initiating infection by hindering their attachment to target cell .
2. Opsonization: Opsonization is a procedure where antibody coat pathogens , enhance their recognition and uptake by phagocytic cells , such as macrophages and neutrophils . When antibody bind to pathogens , the Fc part of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can as well activate the complement system , a series of protein that work in tandem to destroy pathogens . Upon stick to to pathogens , sure antibody can trigger the complement cascade , leading to the formation of the membrane attack complex ( MAC ) that directly lyses sure bacteria and viruses . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , farther enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological roles , antibodies serve as essential tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insight into the individual ’ s humoral immunity condition . Techniques like radial immunodiffusion and immunoelectrophoresis exist commonly utilize to evaluate these antibodies , aiding in the diagnosis and monitoring of respective disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibodies by B cell in reception to foreign antigens . This mechanism has been instrumental in defending against various pathogens throughout history . Hither , we illuminate two discrete examples of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical records , include the discovery of smallpox wound on the mummy of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impact , particularly decimating indigenous population in the Americas and Australia . However , by the end of 1979 , a global vaccination campaign successfully eradicated the , marking a massive accomplishment in the annals of medicine .

The origins of vaccination can exist trace back to Edward Jenner ’ s sharp observation regarding the opposition of milkmaids to smallpox during its rampant gap . Prior to Jenner ’ s study , variolation , a pattern involving the intentional introduction of pus from smallpox victim into healthy individual , was apply as a fundamental shape of inoculation . While the underlie mechanisms of the secondary humoral immune reaction were not yet understood , the principle of induce a mild infection to bestow future security was recognized .

Jenner ’ s groundbreaking experiment involve the inoculation of a young son with pus derive from cowpox sores of a milkmaid . Remarkably , the boy demonstrate immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing undermine or inactivated pathogens , innovative approaches were necessitate due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector scheme . Utilize a genetically modified chimpanzee cold virus , known to evoke robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human body . This alien protein triggers the chief humoral reply , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines deliver the genetic blueprint for the COVID-19 spike protein directly into cells . The cell then synthesize the spike protein , initiating the humoral immune answer . Contrary to some misconceptions , mRNA vaccines do not vary human DNA . Instead , they harness the cellular machinery for protein synthesis , bypass the transcription phase and directly lead up translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system live a complex network of cell and protein that defends the torso against pathogens . It can equal broadly categorized into two chief types : humoral immunity and cell-mediated immunity . Each type hold distinct characteristic and functions . Here , we specify the differences between these two branches of the immune reception .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produced	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cell , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ stand for membranous .	TCR receptors
Accessory receptors require	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing cost need	No ( Unprocessed antigen live realize . )	Yes ( Antigen are first work on and then introduce by MHC of antigen-presenting cell )
Major secretory cells	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cell	No	Yes

Quiz

Which cell are primarily responsible for producing antibody in the humoral immune response ?
a ) T cells
b ) Macrophages
c ) B cell
d ) Dendritic cell

Show reply

Which type of immunity cost bestow by the product of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show reply

Which of the following is NOT a office of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show answer

The chief immune answer is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit equal a characteristic of the secondary humoral immune answer ?
a ) Slower onset than the principal response
b ) Abject antibody concentration than the primary reception
100 ) Product of memory B cells
d ) Absence of IgG production

Show answer

Which type of cell present antigen to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cell
d ) Memory cell

Show response

Which antibody cost primarily found in mucosal surface and secretions ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show result

Which of the following equal NOT a characteristic of monoclonal antibody ?
a ) Develop by a single clone of cells
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Apply in diagnostic and therapeutic applications

Show answer

The procedure by which antibodies enhance the phagocytosis of pathogens equal called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show result

Which of the pursuit exist the primary office of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
c ) Facilitate phagocytosis by tie up to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

A . Instructive Theory

This theory state that an immunocompetent cell inherently possess the capability to produce a myriad of antibodies . The antigen , upon introduction , instructs these cells to yield specific antibody complementary to itself . Two sub-theories further elucidate this concept :

1. Direct Template Theory:
   • Proposed by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , direct the formation of the antibody . The resulting antibody molecule follow a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Introduced by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon entering antibody-producing cell , induce a hereditary change . This change involves the integration of the antigenic determinant ’ sec genocopy into the genome , which be then passed on to progeny cell . However , this explanation get lost favor over time .

B . Selective Possibility

These theory propose that the body already possess a repertoire of possible antibody , and the introduction of an antigen merely selects the appropriate unity . Three sub-theories further item this conception :

1. Slope Chain Theory:
   • Demonstrate by Ehrlich in 1898 .
   • Argues that immunocompetent cells have rise receptors that can interact with antigen possessing complementary side chains . Upon antigen introduction , these receptors tie up with the antigen , becoming inactive . To compensate , the cell overproduces like receptors , which are then released as antibodies .
2. Theory:
   • Proposed by Jerne in 1955 .
   • Advise that during fetal evolution , the body produces globulin molecules against all conceivable antigens . Upon antigen introduction , the antigen selectively tie up to the most complementary globulin molecule , stimulate the product of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduced by Burnet in 1957 .
   • Proposes that during fetal development , a immense array of immunologically competent cell clones , each with a unique antibody convention , is produce . Each of these cells expresses membrane receptors specific to a special antigen , determined before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the couple receptor exist touch off , proliferates , and raise the corresponding antibody . This theory , widely assume today , bid insights into immunological specificity , memory , and the ability to recognize between self and non-self .

Factors affecting production of antibody

The production of antibodies , a pivotal aspect of the immune reception , be influenced by a myriad of component . Understanding these determinants live essential for both basic immunology and clinical applications . Herein , we dig into the significant factor that modulate antibody production :

1. Genetic Factors:
   • The genetic makeup of an prescribe its response to antigen . Some are responders , give rise antibody upon exposure , while others , termed nonresponders , do not .
   • The immune reaction ( Ir ) gene , located on the short arm of chromosome six , regulate these variation .
2. Years:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , marked by the growing of lymphoid organs , exist reach by age 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiencies , such as those of amino acid and vitamin , can curtail antibody product .
4. Route of Antigen Administration:
   • The style of antigen delivery act a pivotal office in eliciting an immune response . Parenteral administration typically induces a more robust response compared to oral or nasal route .
5. Dose of Antigen:
   • An optimum dosage of antigen exist essential for a maximal immune response . Extremely high or abject dosage can run to immunological paralysis , a state of reduced immune responsiveness .
6. Multiple Antigens:
   • Concurrent establishment of multiple antigen can result to vary antibody answer due to antigenic competitor . The precise preparation and proportion of these antigens be crucial for achieving hope outcomes .
7. Adjuvants:
   • Adjuvants are content that enhance the immunogenicity of antigens by prolonging antigenic stimulus . Examples include Freund ’ s incomplete and utter adjuvants , aluminum salts , and other substances like silica particles .
8. Immunosuppressive Agents:
   • These agent dampen the immune reply and live apply in scenarios like transplantation surgeries . Lesson include :
     • X-irradiation: Impedes antibody production post 24 hours of exposure .
     • Radiometric Drugs: Specifically direct B cell , inhibit their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets disseminate lymphocytes , give up those in lymphoid organ .

Monoclonal Antibodies

Monoclonal antibody ( mAbs ) are a grade of antibody derived from a single cell lineage , ensuring their homogeneity . Unlike polyclonal antibody , which live produced by multiple plasma cell clones and exist heterologous in nature , monoclonal antibodies are specific to a single antigenic determinant .

Ancestry and Distinction: Monoclonal antibodies originate from circumstance like multiple myeloma , where a singular plasma cell clone raise antibody against a specific antigenic determinant . This specificity contrast with polyclonal antibody , which arise from various plasma cell clones in response to an antigen .

Product Methodology: The pioneering method for monoclonal antibody production be introduced by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique call for the universe of hybridomas , which equal take form by mix myeloma cells with antibody-producing cell . These hybridomas , once institute , can indefinitely grow monoclonal antibody , proving invaluable for research and diagnostic function .

The process involves :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ sec spleen with mouse myeloma cell that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion using agent like polyethylene glycol .
4. Culturing the fused cells in a medium ( HAT medium ) that confirm hybrid cell growth but inhibits the growth of parent cell .
5. Screening the resulting cell clones for antibody production against the prey antigen .
6. Choose and perpetually culturing the clones that produce the desire antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody place challenge for therapeutic use in man . Consequently , advancements led to the evolution of human monoclonal antibody , including chimeric antibodies . These chimeric antibodies , compile of human constant region and mouse varying area , live make up explore for leukemia treatment . Moreover , they can exist employ to direct tumor cell either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibody

Antibody , as well know as immunoglobulins , bring a pivotal role in the immune system ’ sec defense mechanisms against pathogens and their associated production . These Y-shaped protein are specifically tailored to distinguish and knock off foreign invaders , ensuring the host ’ s protection against various infection . Herein , we delve into the multifaceted functions of antibodies :

1. Neutralization: One of the main function of antibodies live neutralization . By binding immediately to pathogens or their toxins , antibodies can inhibit their ability to attach to and infect horde cells . For instance , antibody specific to bacterial toxins can block the toxin ’ s interaction with host cell , thereby neutralizing its harmful effects . Likewise , antibodies can prevent virus or bacteria from initiating infection by hinder their attachment to direct cell .
2. Opsonization: Opsonization exist a process where antibody coat pathogens , enhance their recognition and intake by phagocytic cells , such as macrophages and neutrophils . When antibody bind to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can also set off the complement system , a series of proteins that form in tandem to destroy pathogens . Upon binding to pathogens , sure antibodies can trigger the complement cascade , head to the formation of the membrane attack complex ( MAC ) that at once lyses sure bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , further enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological use , antibodies serve as essential tools in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insights into the individual ’ sec humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis are usually employed to evaluate these antibody , assist in the diagnosis and monitoring of various disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibodies by B cells in reception to alien antigen . This mechanism hold live instrumental in defending against various pathogens throughout story . Here , we clarify two distinct lesson of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical records , include the discovery of smallpox lesions on the mamma of Pharaoh Ramses V , hint the ancient prevalence of this deadly disease . Smallpox had catastrophic impact , peculiarly decimating indigenous populations in the Americas and Australia . Still , by the goal of 1979 , a global vaccination campaign successfully eradicated the , marking a massive achievement in the annals of medicine .

The ancestry of vaccination can be retrace back to Edward Jenner ’ s sharp observation regarding the opposition of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ s study , variolation , a practice require the intentional introduction of pus from smallpox victim into healthy individuals , exist apply as a fundamental kind of inoculation . While the underlying mechanisms of the secondary humoral immune response were not yet understood , the principle of inducing a mild infection to bestow future security live distinguish .

Jenner ’ s groundbreaking experiment involved the inoculation of a youthful son with pus descend from cowpox sores of a milkmaid . Remarkably , the son exhibited immunity to subsequent smallpox exposure , set the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge pose by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employ weakened or inactivated pathogens , innovative approaches were necessitated due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector strategy . Utilizing a genetically modified chimpanzee cold virus , known to evoke robust immune answer , the vaccine introduces the SARS-CoV-2 spike protein into the human body . This foreign protein trigger the main humoral response , culminate in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines redeem the genetic blueprint for the COVID-19 spike protein instantly into cells . The cells then synthesize the spike protein , lead up the humoral immune reply . Contrary to some misconception , mRNA vaccines do not alter human DNA . Instead , they harness the cellular machinery for protein synthesis , bypassing the transcription stage and immediately initiating translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity five cell mediated immunity

The immune system is a complex network of cells and proteins that oppose the body against pathogens . It can be broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type own distinct characteristic and functions . Here , we delineate the differences between these two branches of the immune reaction .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody raise	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cell , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ tolerate for membranous .	TCR receptors
Accessory receptors require	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is call for	No ( Unprocessed antigens equal make out . )	Yes ( Antigens are first work on and then presented by MHC of antigen-presenting cell )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( signal proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cells	No	Yes

Quiz

Which cell exist primarily responsible for producing antibody in the humoral immune reception ?
a ) T cells
b ) Macrophages
100 ) B cell
d ) Dendritic cell

Show response

Which type of immunity is conferred by the production of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show result

Which of the pursuit is NOT a affair of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show answer

The principal immune reception is characterize by the production of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit is a characteristic of the secondary humoral immune response ?
a ) Slower onset than the primary response
b ) Low antibody concentration than the chief response
c ) Production of memory B cells
d ) Absence of IgG production

Show answer

Which type of cells present antigen to immunocompetent cells ?
a ) T cells
b ) Antigen-presenting cells ( APCs )
c ) Plasma cells
d ) Memory cells

Show result

Which antibody is mainly found in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit exist NOT a characteristic of monoclonal antibody ?
a ) Develop by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Employ in diagnostic and therapeutic application

Show answer

The process by which antibodies enhance the phagocytosis of pathogens is called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show result

Which of the following cost the primary function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
c ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Direct Template Theory:
   • Propose by Breinl and Haurowitz in 1930 .
   • Suggests that the antigen or its determinants number as a template , guiding the formation of the antibody . The resulting antibody particle adopts a structure complementary to the antigenic template .
2. Indirect Template Theory:
   • Bring in by Burnet and Fenner in 1949 .
   • Proposes that antigenic determinants , upon go into antibody-producing cells , get a ancestral change . This change involves the integration of the antigenic determinant ’ sec genocopy into the genome , which be then passed on to progeny cell . Still , this explanation make lost favor over time .

• Propose by Breinl and Haurowitz in 1930 .
• Advise that the antigen or its determinants act as a template , guiding the formation of the antibody . The resulting antibody particle adopt a structure complementary to the antigenic template .

• Bring in by Burnet and Fenner in 1949 .
• Proposes that antigenic determinants , upon go into antibody-producing cells , induce a hereditary change . This change involves the integration of the antigenic determinant ’ sec genocopy into the genome , which be then pass on to progeny cell . However , this explanation has lost favor over time .

B . Selective Theory

These theory suggest that the body already possess a repertoire of potential antibodies , and the introduction of an antigen only selects the appropriate ace . Three sub-theories further detail this conception :

1. Slope Chain Theory:
   • Introduce by Ehrlich in 1898 .
   • Argues that immunocompetent cells have surface receptors that can interact with antigen possessing complementary side irons . Upon antigen introduction , these receptors bind with the antigen , become inactive . To compensate , the cell overproduces like receptors , which exist then released as antibody .
2. Theory:
   • Proposed by Jerne in 1955 .
   • Suggests that during fetal evolution , the torso produces globulin molecule against all conceivable antigens . Upon antigen introduction , the antigen selectively bind to the most complementary globulin particle , stimulate the product of the corresponding antibody .
3. Clonal Selection Theory:
   • Introduced by Burnet in 1957 .
   • Proposes that during fetal evolution , a huge array of immunologically competent cell clones , each with a unique antibody rule , is produced . Each of these cell expresses membrane receptors specific to a particular antigen , determined before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the agree receptor is trigger , proliferates , and produces the corresponding antibody . This theory , widely assume today , put up insights into immunological specificity , memory , and the power to separate between self and non-self .

• Presented by Ehrlich in 1898 .
• Argues that immunocompetent cell make come out receptors that can interact with antigens possess complementary side chains . Upon antigen introduction , these receptors tie up with the antigen , become still . To compensate , the cell overproduces like receptors , which are then released as antibodies .

• Suggest by Jerne in 1955 .
• Suggests that during fetal evolution , the torso raise globulin molecules against all conceivable antigen . Upon antigen introduction , the antigen selectively stick to to the most complementary globulin particle , stimulate the product of the corresponding antibody .

• Introduce by Burnet in 1957 .
• Proposes that during fetal development , a vast array of immunologically competent cell clones , each with a unique antibody pattern , is produced . Each of these cell express membrane receptors specific to a peculiar antigen , determined before the cell ’ s exposure to the antigen . Upon antigen introduction , the cell with the correspond receptor live activate , proliferates , and produce the corresponding antibody . This theory , widely consent today , offers insight into immunological specificity , memory , and the ability to differentiate between self and non-self .

Component affecting product of antibody

The product of antibody , a pivotal aspect of the immune reception , is determine by a myriad of factor . Understand these determinants live essential for both basic immunology and clinical application . Herein , we delve into the significant factors that modulate antibody production :

1. Genetic Component:
   • The genetic makeup of an order its response to antigens . Some equal responders , produce antibodies upon exposure , while others , termed nonresponders , do not .
   • The immune reaction ( Ir ) gene , place on the short branch of chromosome six , regulate these variations .
2. Age:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , set by the maturation of lymphoid organ , equal achieved by ages 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally strike both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acids and vitamin , can restrict antibody product .
4. Route of Antigen Administration:
   • The mode of antigen delivery plays a pivotal use in eliciting an immune answer . Parenteral administration typically have a more robust response compare to oral or nasal routes .
5. Dose of Antigen:
   • An optimal dose of antigen cost essential for a maximum immune reaction . Extremely high or low doses can lead to immunological paralysis , a state of reduce immune responsiveness .
6. Multiple Antigens:
   • Simultaneous administration of multiple antigen can head to depart antibody reaction due to antigenic competitor . The exact preparation and proportion of these antigens are crucial for attain desired outcomes .
7. Adjuvants:
   • Adjuvants exist meaning that enhance the immunogenicity of antigens by prolonging antigenic stimulus . Examples include Freund ’ s incomplete and complete adjuvants , aluminum salt , and other message like silica particles .
8. Immunosuppressive Agent:
   • These agents moisten the immune reply and exist employed in scenarios like transplantation surgeries . Instance include :
     • X-irradiation: Impedes antibody product post 24 hour of exposure .
     • Radiometric Drugs: Specifically direct B cells , conquer their replication .
     • Corticosteroids: Diminish the reactivity of B and T lymphocytes by regulate interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Object circulating lymphocytes , spare those in lymphoid organs .

Monoclonal Antibodies

Monoclonal antibodies ( mAbs ) are a category of antibody infer from a single cell lineage , see to it their homogeneity . Unlike polyclonal antibodies , which are give rise by multiple plasma cell clones and equal heterologous in nature , monoclonal antibodies are specific to a single antigenic determinant .

Source and Distinction: Monoclonal antibody originate from conditions like multiple myeloma , where a singular plasma cell clone produce antibody against a specific antigenic determinant . This specificity contrasts with polyclonal antibody , which develop from various plasma cell clones in answer to an antigen .

Product Methodology: The pioneering method for monoclonal antibody production was introduce by Kohler and Milstein in 1975 , bring in them the Nobel Prize in 1984 . Their technique require the creation of hybridomas , which cost formed by fuse myeloma cells with antibody-producing cell . These hybridomas , once establish , can indefinitely produce monoclonal antibody , proving invaluable for inquiry and diagnostic purposes .

The process demand :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ sec spleen with mouse myeloma cell that miss the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion employ agents like polyethylene glycol .
4. Culturing the fused cells in a medium ( HAT medium ) that affirm hybrid cell growth but inhibits the increase of parent cells .
5. Shield the resulting cell clones for antibody production against the aim antigen .
6. Selecting and perpetually culturing the clones that give rise the desire antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody lay challenge for therapeutic usage in humans . Accordingly , advancements led to the development of human monoclonal antibodies , including chimeric antibody . These chimeric antibody , composed of human constant part and mouse varying part , are live explored for leukemia discussion . Furthermore , they can be employed to target tumor cell either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibody

Antibodies , also know as immunoglobulins , meet a pivotal role in the immune system ’ s defense mechanisms against pathogens and their associated merchandise . These Y-shaped protein are specifically tailored to recognize and knock off alien invaders , ensuring the horde ’ s protection against respective infection . Herein , we delve into the multifaceted functions of antibody :

1. Neutralization: One of the chief part of antibody is neutralization . By bind directly to pathogens or their toxins , antibody can conquer their power to attach to and infect host cells . For instance , antibodies specific to bacterial toxins can obstruct the toxin ’ s interaction with horde cell , thereby neutralize its harmful effects . Similarly , antibodies can forestall virus or bacteria from initiating infection by hinder their attachment to target cell .
2. Opsonization: Opsonization is a procedure where antibodies coat pathogens , enhance their recognition and intake by phagocytic cell , such as macrophages and neutrophils . When antibody tie up to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can too touch off the complement system , a series of proteins that solve in tandem to destroy pathogens . Upon tie up to pathogens , certain antibody can spark the complement cascade , leading to the formation of the membrane attack complex ( MAC ) that instantly lyses sure bacteria and viruses . Additionally , some by-product of the complement cascade , like C3b , can opsonize pathogens , further enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological use , antibody suffice as crucial tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can supply insights into the individual ’ sec humoral immunity status . Technique like radial immunodiffusion and immunoelectrophoresis are usually employed to evaluate these antibodies , aiding in the diagnosis and monitoring of various disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibodies by B cells in reaction to foreign antigens . This mechanism has be instrumental in oppose against respective pathogens throughout history . Here , we clear up two distinct lesson of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical disc , including the discovery of smallpox lesions on the mama of Pharaoh Ramses V , hint the ancient prevalence of this deadly disease . Smallpox had catastrophic impacts , particularly decimating indigenous population in the Americas and Australia . Still , by the end of 1979 , a global vaccination campaign successfully eradicated the , marking a monumental achievement in the annals of medicine .

The origins of vaccination can be traced back to Edward Jenner ’ s astute observation consider the opposition of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ s study , variolation , a practice call for the intentional introduction of pus from smallpox victims into sound individuals , was apply as a fundamental form of inoculation . While the underlying mechanisms of the secondary humoral immune response were not yet understood , the principle of inducing a meek infection to confer future security exist realize .

Jenner ’ s groundbreaking experiment involved the inoculation of a young boy with pus derived from cowpox sores of a milkmaid . Remarkably , the boy exhibited immunity to subsequent smallpox exposure , lay the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines employ weakened or inactivated pathogens , innovative approaches were necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector scheme . Utilizing a genetically modified chimpanzee cold virus , know to elicit robust immune reception , the vaccine introduces the SARS-CoV-2 spike protein into the human torso . This foreign protein triggers the primary humoral answer , culminating in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines deliver the genetic blueprint for the COVID-19 spike protein straight into cell . The cells then synthesize the spike protein , initiating the humoral immune reply . Contrary to some misconception , mRNA vaccines do not change human DNA . Instead , they harness the cellular machinery for protein synthesis , bypass the transcription phase and directly originate translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity five cell mediated immunity

The immune system is a complex network of cells and proteins that defends the torso against pathogens . It can equal broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type own distinct characteristic and functions . Hither , we delineate the difference between these two branches of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody give rise	Yes	No
Set off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cell , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ bear for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing cost needed	No ( Unprocessed antigen be recognized . )	Yes ( Antigens are first processed and then presented by MHC of antigen-presenting cell )
Major secretory cells	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( indicate proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells are primarily responsible for producing antibody in the humoral immune answer ?
a ) T cell
b ) Macrophages
100 ) B cells
d ) Dendritic cells

Show solution

Which type of immunity equal bestow by the production of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show response

Which of the following is NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show solution

The primary immune reply live characterized by the production of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show solution

Which of the following is a characteristic of the secondary humoral immune response ?
a ) Slower onset than the main reception
b ) Lower antibody concentration than the main reply
100 ) Production of memory B cells
d ) Absence of IgG production

Show answer

Which type of cell present antigen to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cells ( APCs )
c ) Plasma cells
d ) Memory cell

Show response

Which antibody cost chiefly found in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit cost NOT a characteristic of monoclonal antibodies ?
a ) Give rise by a single clone of cell
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show answer

The procedure by which antibody enhance the phagocytosis of pathogens exist called :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show response

Which of the pursuit is the chief function of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cell
d ) Cause direct cell lysis

Show reply

FAQ

Reference

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Genetic Component:
   • The genetic makeup of an dictates its response to antigen . Some are responders , produce antibodies upon photograph , while others , termed nonresponders , act not .
   • The immune reply ( Ir ) gene , place on the short arm of chromosome six , governs these variations .
2. Years:
   • Neonates and embryos display an underdeveloped immune competence .
   • Full immunological competence , set by the growing of lymphoid organs , is attain by age 5-7 for IgG and 10-15 for IgA .
3. Nutritional Status:
   • Malnutrition detrimentally affects both humoral and cell-mediated immunity .
   • Specific deficiency , such as those of amino acids and vitamins , can curtail antibody production .
4. Route of Antigen Administration:
   • The mode of antigen rescue plays a pivotal role in elicit an immune answer . Parenteral administration typically make a more robust answer compared to oral or nasal road .
5. Dose of Antigen:
   • An optimal dose of antigen is essential for a maximal immune reply . Extremely high or low doses can result to immunological paralysis , a state of reduced immune responsiveness .
6. Multiple Antigen:
   • Concurrent administration of multiple antigens can take to change antibody reaction due to antigenic competitor . The exact expression and proportion of these antigens are crucial for attain want effect .
7. Adjuvants:
   • Adjuvants are substances that enhance the immunogenicity of antigen by prolonging antigenic stimulation . Examples include Freund ’ s incomplete and utter adjuvants , aluminum salts , and early content like silica particles .
8. Immunosuppressive Agents:
   • These agents dampen the immune answer and live utilize in scenarios like transplantation surgeries . Examples include :
     • X-irradiation: Impedes antibody product place 24 hour of exposure .
     • Radiometric Drugs: Specifically target B cell , inhibiting their replication .
     • Corticosteroids: Lessen the reactivity of B and T lymphocytes by modulating interleukin synthesis .
     • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
     • Antilymphocyte Serum ( ALS ): Targets disseminate lymphocytes , sparing those in lymphoid organs .

• The genetic makeup of an prescribe its answer to antigen . Some are responders , develop antibodies upon photograph , while others , termed nonresponders , cause not .
• The immune answer ( Ir ) gene , locate on the short arm of chromosome six , regulate these version .

• Neonates and embryos display an underdeveloped immune competence .
• Full immunological competence , mark by the growing of lymphoid organ , is achieved by ages 5-7 for IgG and 10-15 for IgA .

• Malnutrition detrimentally affects both humoral and cell-mediated immunity .
• Specific deficiency , such as those of amino acid and vitamins , can restrict antibody production .

• The fashion of antigen delivery meet a pivotal use in elicit an immune response . Parenteral organization typically induces a more robust reception compared to oral or nasal routes .

• An optimum dose of antigen is essential for a maximum immune response . Extremely high or abject dose can lead to immunological paralysis , a province of reduced immune responsiveness .

• Concurrent administration of multiple antigen can result to vary antibody responses due to antigenic competitor . The exact expression and proportion of these antigen are crucial for achieving desired outcomes .

• Adjuvants exist substances that enhance the immunogenicity of antigens by prolong antigenic stimulation . Examples include Freund ’ s incomplete and all over adjuvants , aluminum salt , and other substances like silica particle .

• These agents moisten the immune response and are apply in scenarios like transplantation surgeries . Lesson include :
  • X-irradiation: Impedes antibody production post 24 hours of photograph .
  • Radiometric Drugs: Specifically direct B cells , inhibiting their replication .
  • Corticosteroids: Lessen the reactivity of B and T lymphocytes by regulate interleukin synthesis .
  • Antimetabolites: Hinder DNA and RNA synthesis , curtailing cell proliferation and differentiation .
  • Antilymphocyte Serum ( ALS ): Targets circulating lymphocytes , sparing those in lymphoid organs .

• X-irradiation: Impedes antibody product place 24 hour of photo .
• Radiometric Drugs: Specifically target B cells , inhibit their replication .
• Corticosteroids: Lessen the reactivity of B and T lymphocytes by regulate interleukin synthesis .
• Antimetabolites: Hinder DNA and RNA synthesis , restrict cell proliferation and differentiation .
• Antilymphocyte Serum ( ALS ): Targets disseminate lymphocytes , sparing those in lymphoid organ .

Monoclonal Antibodies

Monoclonal antibodies ( mAbs ) are a grade of antibodies derived from a single cell lineage , ensuring their homogeneity . Unlike polyclonal antibody , which exist produced by multiple plasma cell clones and exist heterologous in nature , monoclonal antibodies exist specific to a single antigenic determinant .

Ancestry and Distinction: Monoclonal antibodies initiate from condition like multiple myeloma , where a singular plasma cell clone produces antibody against a specific antigenic determinant . This specificity contrasts with polyclonal antibodies , which develop from respective plasma cell clones in reply to an antigen .

Production Methodology: The pioneering method for monoclonal antibody production was bring in by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique demand the universe of hybridomas , which equal formed by fusing myeloma cells with antibody-producing cells . These hybridomas , once institute , can indefinitely raise monoclonal antibody , test priceless for inquiry and diagnostic purposes .

The process call for :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ sec spleen with mouse myeloma cell that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion employ agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT medium ) that stand hybrid cell growth but inhibit the growth of parent cells .
5. Screening the resulting cell clones for antibody production against the prey antigen .
6. Selecting and perpetually culturing the clones that make the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody posed challenges for therapeutic role in man . Accordingly , advancements led to the evolution of human monoclonal antibodies , including chimeric antibodies . These chimeric antibody , write of human constant regions and mouse varying region , are make up explored for leukemia discussion . Moreover , they can be employed to direct tumor cells either by deliver toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibody

Antibody , as well know as immunoglobulins , play a pivotal role in the immune system ’ sec defense mechanism against pathogens and their associated products . These Y-shaped protein exist specifically tailored to recognize and knock off foreign invaders , ensuring the horde ’ sec protection against various infections . Herein , we delve into the multifaceted functions of antibodies :

1. Neutralization: One of the primary roles of antibody equal neutralization . By tie up immediately to pathogens or their toxins , antibodies can inhibit their power to bind to and infect host cell . For instance , antibody specific to bacterial toxins can obstruct the toxin ’ s interaction with horde cells , thereby neutralizing its harmful effects . Similarly , antibody can prevent viruses or bacteria from initiating infection by hindering their attachment to direct cell .
2. Opsonization: Opsonization be a process where antibody coat pathogens , enhancing their realization and intake by phagocytic cell , such as macrophages and neutrophils . When antibodies tie up to pathogens , the Fc area of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can as well trigger the complement system , a series of proteins that work in tandem to ruin pathogens . Upon binding to pathogens , certain antibody can trigger the complement cascade , head to the formation of the membrane attack complex ( MAC ) that instantly lyses sure bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , farther enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological role , antibodies suffice as crucial tool in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can leave insights into the individual ’ sec humoral immunity position . Technique like radial immunodiffusion and immunoelectrophoresis be commonly utilize to measure these antibody , aid in the diagnosis and monitoring of various diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , be characterized by the product of antibodies by B cell in reception to foreign antigen . This mechanism has be instrumental in defending against various pathogens throughout history . Here , we elucidate two discrete lesson of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox wound on the mummy of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impact , particularly decimating indigenous populations in the Americas and Australia . Still , by the end of 1979 , a global vaccination movement successfully eradicated the , marking a monumental accomplishment in the annals of medicine .

The origins of vaccination can be retrace back to Edward Jenner ’ s sharp observation regarding the resistance of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ s study , variolation , a practice involve the intentional introduction of pus from smallpox victims into healthy individual , live employed as a fundamental form of inoculation . While the underlie mechanism of the secondary humoral immune answer were not yet understood , the principle of induce a mild infection to confer next protection equal recognized .

Jenner ’ s groundbreaking experiment involved the inoculation of a young son with pus descend from cowpox sores of a milkmaid . Remarkably , the boy exhibited immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing undermine or inactivated pathogens , innovative approaches were necessitated due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine apply a viral vector strategy . Utilize a genetically change chimpanzee cold virus , know to arouse robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human torso . This alien protein triggers the primary humoral response , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines bear the genetic blueprint for the COVID-19 spike protein instantly into cell . The cells then synthesize the spike protein , initiating the humoral immune response . Contrary to some misconceptions , mRNA vaccines cause not change human DNA . Instead , they harness the cellular machinery for protein synthesis , bypass the transcription stage and right away lead up translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system is a complex network of cell and proteins that defends the body against pathogens . It can be broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type has distinct characteristics and functions . Hither , we define the differences between these two branches of the immune answer .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies produced	Yes	No
Set off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , viruses , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors require	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing exist require	No ( Unprocessed antigens are recognized . )	Yes ( Antigens are first processed and then confront by MHC of antigen-presenting cell )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( signal proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cells	No	Yes

Quiz

Which cell are mainly responsible for produce antibodies in the humoral immune reply ?
a ) T cell
b ) Macrophages
c ) B cell
d ) Dendritic cells

Show answer

Which type of immunity be conferred by the production of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show solution

Which of the pursuit be NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show answer

The main immune reaction is characterized by the product of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the pursuit be a characteristic of the secondary humoral immune reception ?
a ) Slow onset than the principal answer
b ) Lower antibody concentration than the primary reply
c ) Product of memory B cells
d ) Absence of IgG production

Show response

Which type of cells present antigen to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cells ( APCs )
c ) Plasma cells
d ) Memory cells

Show answer

Which antibody is mainly get in mucosal surface and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit equal NOT a characteristic of monoclonal antibody ?
a ) Give rise by a single clone of cell
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic applications

Show result

The procedure by which antibodies enhance the phagocytosis of pathogens is called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the following be the primary affair of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
100 ) Facilitate phagocytosis by binding to Fc receptors on phagocytic cells
d ) Inducing direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Ancestry and Distinction: Monoclonal antibody spring up from circumstance like multiple myeloma , where a funny plasma cell clone produce antibodies against a specific antigenic determinant . This specificity contrast with polyclonal antibodies , which stand up from several plasma cell clones in response to an antigen .

Product Methodology: The pioneering method for monoclonal antibody production was introduced by Kohler and Milstein in 1975 , earning them the Nobel Prize in 1984 . Their technique involved the universe of hybridomas , which live form by fusing myeloma cells with antibody-producing cell . These hybridomas , once establish , can indefinitely raise monoclonal antibodies , proving priceless for research and diagnostic purposes .

The procedure involves :

1. Inoculating an beast , typically a mouse , with the desired antigen .
2. Fuse the lymphocytes from the animal ’ s spleen with mouse myeloma cells that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion using agents like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT media ) that supports hybrid cell increase but inhibits the increase of parent cell .
5. Shield the resulting cell clones for antibody production against the prey antigen .
6. Selecting and perpetually culturing the clones that raise the desire antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody posed challenge for therapeutic use in humans . Consequently , advancements result to the development of human monoclonal antibody , include chimeric antibodies . These chimeric antibody , compile of human constant region and mouse variable region , be be explored for leukemia treatment . Moreover , they can exist employ to direct tumor cell either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Office of Antibody

Antibody , as well known as immunoglobulins , play a pivotal purpose in the immune system ’ sec defense mechanism against pathogens and their associated product . These Y-shaped proteins are specifically tailored to recognize and neutralize alien invaders , insure the horde ’ s security against various infection . Herein , we delve into the multifaceted office of antibodies :

1. Neutralization: One of the primary part of antibody equal neutralization . By binding directly to pathogens or their toxins , antibody can suppress their ability to bind to and infect horde cells . For instance , antibody specific to bacterial toxins can obstruct the toxin ’ s interaction with horde cells , thereby neutralizing its harmful impression . Likewise , antibodies can prevent virus or bacteria from originate infections by hindering their attachment to target cell .
2. Opsonization: Opsonization is a procedure where antibodies coat pathogens , enhancing their recognition and intake by phagocytic cell , such as macrophages and neutrophil . When antibodies tie to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can too activate the complement system , a series of proteins that operate in tandem to ruin pathogens . Upon tie up to pathogens , certain antibody can trigger the complement cascade , conduct to the formation of the membrane attack complex ( MAC ) that directly lyses sure bacteria and viruses . Additionally , some by-product of the complement cascade , like C3b , can opsonize pathogens , farther enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological roles , antibody serve as essential tool in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can allow for insight into the individual ’ sec humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis are usually employ to assess these antibody , aiding in the diagnosis and monitoring of various diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , cost characterized by the product of antibodies by B cell in reception to foreign antigen . This mechanism has been instrumental in defending against several pathogens throughout story . Hither , we illuminate two distinct example of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical records , include the discovery of smallpox lesions on the mummy of Pharaoh Ramses V , indicate the ancient prevalence of this deadly disease . Smallpox hold catastrophic impacts , particularly decimating indigenous population in the Americas and Australia . However , by the goal of 1979 , a global vaccination cause successfully eradicated the , note a monumental achievement in the annals of medicine .

The ancestry of vaccination can be trace back to Edward Jenner ’ s astute observation involve the resistor of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ s work , variolation , a practice involve the intentional introduction of pus from smallpox victims into sound individuals , cost employed as a fundamental form of inoculation . While the underlie mechanisms of the secondary humoral immune reaction make up not as yet understood , the principle of stimulate a meek infection to confer future security be realize .

Jenner ’ s groundbreaking experiment necessitate the inoculation of a young boy with pus derive from cowpox sores of a milkmaid . Unusually , the son exhibited immunity to subsequent smallpox exposure , place the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing weakened or inactivated pathogens , innovative approaches were necessitate due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector scheme . Utilizing a genetically change chimpanzee cold virus , know to provoke robust immune reaction , the vaccine bring in the SARS-CoV-2 spike protein into the human body . This alien protein triggers the principal humoral response , culminating in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines bear the genetic design for the COVID-19 spike protein directly into cell . The cells then synthesize the spike protein , initiating the humoral immune response . Contrary to some misconception , mRNA vaccines do not vary human DNA . Instead , they harness the cellular machinery for protein synthesis , bypass the transcription phase and directly initiating translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system is a complex network of cell and protein that defend the body against pathogens . It can exist broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type have distinct characteristics and functions . Hither , we specify the differences between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies produced	Yes	No
Trigger by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cells , viruses , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stand for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigens are realize . )	Yes ( Antigen cost first work on and then demonstrate by MHC of antigen-presenting cells )
Major secretory cell	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( indicate protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cell are chiefly responsible for produce antibodies in the humoral immune response ?
a ) T cell
b ) Macrophages
100 ) B cells
d ) Dendritic cells

Show reply

Which type of immunity is conferred by the product of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show result

Which of the pursuit live NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show answer

The primary immune reply be characterized by the production of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show solution

Which of the following cost a characteristic of the secondary humoral immune response ?
a ) Slow onset than the principal response
b ) Humble antibody concentration than the main reply
c ) Production of memory B cell
d ) Absence of IgG production

Show solution

Which type of cells present antigens to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cell
d ) Memory cell

Show reply

Which antibody cost chiefly base in mucosal surfaces and secretion ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the following cost NOT a characteristic of monoclonal antibody ?
a ) Give rise by a single clone of cells
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Utilize in diagnostic and therapeutic application

Show answer

The process by which antibodies enhance the phagocytosis of pathogens is called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show result

Which of the following exist the primary occasion of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
100 ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cell
d ) Induce direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Production Methodology: The pioneering method for monoclonal antibody production live introduce by Kohler and Milstein in 1975 , bring in them the Nobel Prize in 1984 . Their technique demand the universe of hybridomas , which are organize by fusing myeloma cell with antibody-producing cell . These hybridomas , once established , can indefinitely produce monoclonal antibody , proving priceless for inquiry and diagnostic purpose .

The process require :

1. Inoculating an animal , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ s spleen with mouse myeloma cell that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion using agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT media ) that supports hybrid cell increase but inhibit the increase of parent cells .
5. Screening the result cell clones for antibody production against the object antigen .
6. Selecting and perpetually culturing the clones that raise the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody posed challenge for therapeutic habit in humans . Consequently , advancements result to the evolution of human monoclonal antibodies , include chimeric antibody . These chimeric antibodies , composed of human constant regions and mouse varying regions , live be explore for leukemia treatment . Furthermore , they can be apply to target tumor cells either by present toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibodies

Antibodies , also known as immunoglobulins , play a pivotal part in the immune system ’ sec defense mechanisms against pathogens and their associated product . These Y-shaped proteins cost specifically tailor to recognize and neutralize alien invaders , assure the host ’ sec security against respective infection . Herein , we dig into the multifaceted functions of antibodies :

1. Neutralization: One of the primary purpose of antibodies is neutralization . By tie up directly to pathogens or their toxins , antibodies can conquer their power to seize to and infect horde cells . For example , antibodies specific to bacterial toxins can block the toxin ’ s interaction with host cells , thereby neutralize its harmful effect . Likewise , antibodies can keep viruses or bacteria from initiating infection by hinder their attachment to direct cells .
2. Opsonization: Opsonization is a process where antibodies coat pathogens , enhancing their realization and uptake by phagocytic cell , such as macrophages and neutrophils . When antibodies bind to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can also trigger the complement system , a series of protein that bring in tandem to ruin pathogens . Upon binding to pathogens , sure antibodies can trigger the complement cascade , leading to the formation of the membrane approach complex ( MAC ) that straight lyses certain bacteria and viruses . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , farther enhancing their phagocytosis .
4. Diagnostic Utility: Beyond their physiological part , antibodies do as crucial tools in diagnostic medicine . The presence and concentration of specific antibodies , such as IgG , IgM , and IgA , in a patient ’ s serum can furnish insights into the individual ’ sec humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis are usually employed to measure these antibody , aiding in the diagnosis and monitoring of respective diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibodies by B cells in response to alien antigen . This mechanism has be instrumental in defending against several pathogens throughout account . Here , we clear up two discrete examples of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical record , include the discovery of smallpox wound on the mamma of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox have catastrophic impacts , particularly decimating indigenous populations in the Americas and Australia . Still , by the end of 1979 , a global vaccination cause successfully eradicated the , mark a monumental accomplishment in the annals of medicine .

The source of vaccination can exist traced back to Edward Jenner ’ s sharp observation regard the resistance of milkmaids to smallpox during its rampant gap . Prior to Jenner ’ sec study , variolation , a pattern necessitate the intentional introduction of pus from smallpox victim into healthy individual , was employed as a fundamental form of inoculation . While the underlie mechanisms of the secondary humoral immune reply live not yet understood , the principle of stimulate a meek infection to bestow future security exist realize .

Jenner ’ s groundbreaking experiment involved the inoculation of a youthful son with pus deduce from cowpox sores of a milkmaid . Remarkably , the son exhibited immunity to subsequent smallpox exposure , put the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employ weakened or inactivated pathogens , innovative approaches were necessitated due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine hire a viral vector scheme . Utilizing a genetically modified chimpanzee cold virus , know to elicit robust immune answer , the vaccine introduce the SARS-CoV-2 spike protein into the human torso . This alien protein trigger the main humoral response , culminating in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines redeem the genetic design for the COVID-19 spike protein directly into cells . The cell then synthesize the spike protein , initiating the humoral immune response . Contrary to some misconceptions , mRNA vaccines cause not change human DNA . Or else , they harness the cellular machinery for protein synthesis , bypass the transcription phase and immediately initiating translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system is a complex network of cells and protein that defend the torso against pathogens . It can be broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type get distinct characteristic and occasion . Here , we delineate the differences between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies give rise	Yes	No
Touch off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cell , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ endure for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is take	No ( Unprocessed antigen cost discern . )	Yes ( Antigens are first work on and then presented by MHC of antigen-presenting cells )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cells	No	Yes

Quiz

Which cells live chiefly responsible for develop antibody in the humoral immune reply ?
a ) T cell
b ) Macrophages
100 ) B cell
d ) Dendritic cell

Show response

Which type of immunity exist bestow by the production of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show response

Which of the pursuit is NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show answer

The primary immune response is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit is a characteristic of the secondary humoral immune reception ?
a ) Slow onset than the principal response
b ) Humble antibody concentration than the main reaction
100 ) Production of memory B cell
d ) Absence of IgG production

Show answer

Which type of cell present antigen to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cells
d ) Memory cells

Show answer

Which antibody is mainly find in mucosal surface and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the following is NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cells
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic applications

Show answer

The procedure by which antibodies enhance the phagocytosis of pathogens is call :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the following is the primary function of the Fc area of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
c ) Facilitating phagocytosis by bind to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show answer

FAQ

Address

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

The process involves :

1. Inoculating an creature , typically a mouse , with the desired antigen .
2. Merge the lymphocytes from the animal ’ s spleen with mouse myeloma cell that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitate cell fusion apply agent like polyethylene glycol .
4. Culturing the fused cells in a medium ( HAT media ) that supports hybrid cell growth but inhibits the growing of parent cells .
5. Screening the result cell clones for antibody production against the prey antigen .
6. Selecting and perpetually culturing the clones that produce the desired antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibody put challenges for therapeutic use in human . Accordingly , advancements led to the development of human monoclonal antibodies , including chimeric antibody . These chimeric antibody , composed of human constant part and mouse varying part , are being search for leukemia treatment . Furthermore , they can be utilize to direct tumor cells either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Affair of Antibodies

Antibody , also known as immunoglobulins , bring a pivotal role in the immune system ’ sec defense mechanism against pathogens and their associated products . These Y-shaped proteins are specifically tailor to realize and knock off alien invaders , ensuring the host ’ s security against respective infections . Herein , we dig into the multifaceted functions of antibody :

1. Neutralization: One of the primary roles of antibodies be neutralization . By binding directly to pathogens or their toxins , antibodies can inhibit their ability to seize to and infect host cells . For instance , antibodies specific to bacterial toxins can block the toxin ’ s interaction with horde cells , thereby knock off its harmful result . Likewise , antibodies can forestall viruses or bacteria from initiating infection by hindering their attachment to direct cell .
2. Opsonization: Opsonization exist a procedure where antibodies coat pathogens , enhance their recognition and intake by phagocytic cell , such as macrophages and neutrophils . When antibody bind to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can also spark the complement system , a series of protein that work in tandem to destroy pathogens . Upon binding to pathogens , certain antibodies can trigger the complement cascade , leading to the formation of the membrane approach composite ( MAC ) that right away lyses sure bacteria and virus . Additionally , some by-product of the complement cascade , like C3b , can opsonize pathogens , further enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological roles , antibody serve as essential tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insight into the individual ’ s humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis equal commonly apply to evaluate these antibodies , assist in the diagnosis and monitoring of various diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , exist characterize by the product of antibodies by B cell in reception to foreign antigens . This mechanism has been instrumental in defending against several pathogens throughout account . Hither , we clarify two discrete examples of humoral immunity , spanning ancient and modern times .

1 . Smallpox and the Advent of Vaccination

Historical disc , including the discovery of smallpox wound on the mamma of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impact , in particular decimating indigenous population in the Americas and Australia . Even so , by the goal of 1979 , a global vaccination campaign successfully eradicated the , score a massive accomplishment in the annals of medicine .

The origins of vaccination can equal follow back to Edward Jenner ’ s sharp observation consider the resistor of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ sec study , variolation , a practice involving the intentional introduction of pus from smallpox victims into healthy individuals , was utilize as a fundamental form of inoculation . While the underlying mechanism of the secondary humoral immune reply exist not still understood , the rationale of bring on a mild infection to confer next protection equal discern .

Jenner ’ s groundbreaking experiment involved the inoculation of a young son with pus derived from cowpox sores of a milkmaid . Unusually , the boy exhibit immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employing undermine or inactivated pathogens , innovative approaches cost necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employ a viral vector strategy . Utilize a genetically alter chimpanzee cold virus , know to elicit robust immune reception , the vaccine introduce the SARS-CoV-2 spike protein into the human torso . This foreign protein touch off the primary humoral reception , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines hand over the genetic blueprint for the COVID-19 spike protein right away into cells . The cells then synthesize the spike protein , initiating the humoral immune reception . Contrary to some misconception , mRNA vaccines do not change human DNA . Rather , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and directly lead up translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity five cell mediated immunity

The immune system equal a complex network of cells and proteins that fight the torso against pathogens . It can equal broadly categorized into two main type : humoral immunity and cell-mediated immunity . Each type have distinct characteristic and functions . Here , we specify the difference between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produce	Yes	No
Touch off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing equal require	No ( Unprocessed antigen are recognized . )	Yes ( Antigens cost first processed and then presented by MHC of antigen-presenting cell )
Major secretory cell	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( signaling protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cells	No	Yes

Quiz

Which cell are primarily responsible for give rise antibodies in the humoral immune response ?
a ) T cells
b ) Macrophages
100 ) B cell
d ) Dendritic cell

Show reply

Which type of immunity equal conferred by the product of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show solution

Which of the pursuit equal NOT a affair of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show answer

The principal immune reaction is characterize by the production of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show response

Which of the pursuit be a characteristic of the secondary humoral immune answer ?
a ) Slow onset than the primary response
b ) Abject antibody concentration than the primary response
c ) Product of memory B cells
d ) Absence of IgG product

Show solution

Which type of cells present antigens to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
c ) Plasma cells
d ) Memory cell

Show answer

Which antibody is primarily find in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit is NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cells
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic applications

Show answer

The process by which antibody enhance the phagocytosis of pathogens is called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the following is the primary function of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitate phagocytosis by bind to Fc receptors on phagocytic cell
d ) Cause direct cell lysis

Show result

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA mode : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Inoculating an creature , typically a mouse , with the desired antigen .
2. Fusing the lymphocytes from the animal ’ s spleen with mouse myeloma cells that lack the enzyme hypoxanthine phosphoribosyl transferase ( HPRT ) .
3. Facilitating cell fusion employ agent like polyethylene glycol .
4. Culturing the fused cell in a medium ( HAT medium ) that supports hybrid cell growth but inhibits the increase of parent cell .
5. Screening the result cell clones for antibody product against the mark antigen .
6. Choose and perpetually culturing the clones that produce the want antibody .

Advancements and Therapeutic Applications: The original mouse-derived monoclonal antibodies posed challenge for therapeutic use in man . Consequently , advancements led to the development of human monoclonal antibody , include chimeric antibody . These chimeric antibodies , compose of human constant regions and mouse varying regions , are being explored for leukemia discussion . Furthermore , they can be employed to direct tumor cells either by delivering toxins , such as diphtheria , or through complement-mediated cytotoxicity .

Function of Antibodies

Antibody , also know as immunoglobulins , play a pivotal role in the immune system ’ sec defense mechanisms against pathogens and their associated products . These Y-shaped proteins exist specifically tailored to discern and neutralize alien invaders , insure the horde ’ s protection against various infection . Herein , we delve into the multifaceted functions of antibodies :

1. Neutralization: One of the main roles of antibody is neutralization . By stick to straight to pathogens or their toxins , antibody can inhibit their ability to attach to and infect horde cells . For instance , antibodies specific to bacterial toxins can obstruct the toxin ’ s interaction with horde cells , thereby neutralizing its harmful effects . Likewise , antibodies can prevent viruses or bacteria from initiating infection by hindering their attachment to target cell .
2. Opsonization: Opsonization live a process where antibody coat pathogens , enhancing their recognition and intake by phagocytic cells , such as macrophages and neutrophil . When antibody bind to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitate the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can too activate the complement system , a series of protein that work in tandem to destroy pathogens . Upon binding to pathogens , certain antibodies can activate the complement cascade , conduct to the formation of the membrane approach composite ( MAC ) that directly lyses certain bacteria and viruses . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , further enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological function , antibody function as crucial tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insights into the individual ’ s humoral immunity condition . Technique like radial immunodiffusion and immunoelectrophoresis are ordinarily employed to measure these antibodies , aiding in the diagnosis and monitoring of various diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , equal characterized by the production of antibodies by B cell in response to alien antigen . This mechanism has been instrumental in defending against respective pathogens throughout history . Hither , we clarify two discrete examples of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox wound on the ma of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox have catastrophic impacts , in particular decimating indigenous populations in the Americas and Australia . Still , by the end of 1979 , a global vaccination movement successfully eradicated the , score a monumental achievement in the annals of medicine .

The source of vaccination can be trace back to Edward Jenner ’ s astute observation regarding the resistance of milkmaids to smallpox during its rampant gap . Prior to Jenner ’ s study , variolation , a pattern involving the intentional introduction of pus from smallpox victim into healthy individuals , live employed as a fundamental figure of inoculation . While the underlying mechanism of the secondary humoral immune reception were not still understood , the rationale of inducing a mild infection to bestow future protection be recognize .

Jenner ’ s groundbreaking experiment involved the inoculation of a young boy with pus derive from cowpox sores of a milkmaid . Unusually , the boy demonstrate immunity to subsequent smallpox exposure , set the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge set by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines employ weaken or inactivated pathogens , innovative approaches live necessitated due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employ a viral vector scheme . Utilize a genetically modify chimpanzee cold virus , known to elicit robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human torso . This alien protein triggers the primary humoral response , culminating in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) engineering . These vaccines hand over the genetic blueprint for the COVID-19 spike protein straight into cells . The cells then synthesize the spike protein , lead up the humoral immune answer . Contrary to some misconceptions , mRNA vaccines do not alter human DNA . Rather , they harness the cellular machinery for protein synthesis , bypass the transcription stage and directly initiating translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity five cell mediated immunity

The immune system is a complex network of cells and protein that defends the torso against pathogens . It can be broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type hold distinct characteristic and office . Hither , we delineate the differences between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies raise	Yes	No
Set off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cell , viruses , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ suffer for membranous .	TCR receptors
Accessory receptors call for	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing cost require	No ( Unprocessed antigens equal recognized . )	Yes ( Antigen are first work on and then presented by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( signal proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cells	No	Yes

Quiz

Which cells exist chiefly responsible for develop antibody in the humoral immune response ?
a ) T cell
b ) Macrophages
c ) B cell
d ) Dendritic cells

Show solution

Which type of immunity is conferred by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show solution

Which of the pursuit exist NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show answer

The primary immune response is characterized by the production of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show result

Which of the following is a characteristic of the secondary humoral immune response ?
a ) Dumb onset than the principal reply
b ) Lower antibody concentration than the primary response
100 ) Product of memory B cell
d ) Absence of IgG product

Show solution

Which type of cells present antigens to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cells ( APCs )
c ) Plasma cell
d ) Memory cells

Show answer

Which antibody is chiefly find in mucosal surface and secretion ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the following exist NOT a characteristic of monoclonal antibodies ?
a ) Give rise by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Utilize in diagnostic and therapeutic applications

Show reply

The procedure by which antibodies enhance the phagocytosis of pathogens is yell :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the pursuit is the main function of the Fc area of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
c ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cells
d ) Inducing direct cell lysis

Show answer

FAQ

Mention

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA fashion : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Function of Antibody

Antibodies , also known as immunoglobulins , act a pivotal use in the immune system ’ s defense mechanism against pathogens and their associated products . These Y-shaped proteins equal specifically tailor to recognize and neutralize foreign invaders , ensure the horde ’ sec security against various infections . Herein , we delve into the multifaceted functions of antibodies :

1. Neutralization: One of the principal part of antibodies is neutralization . By binding directly to pathogens or their toxins , antibodies can inhibit their ability to bind to and infect horde cell . For instance , antibodies specific to bacterial toxins can obstruct the toxin ’ s interaction with host cells , thereby neutralize its harmful effects . Similarly , antibody can keep viruses or bacteria from initiate infection by hindering their attachment to target cell .
2. Opsonization: Opsonization cost a process where antibodies coat pathogens , enhancing their recognition and uptake by phagocytic cells , such as macrophages and neutrophil . When antibody bind to pathogens , the Fc region of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibodies can also activate the complement system , a series of protein that work in tandem to destroy pathogens . Upon stick to to pathogens , sure antibodies can touch off the complement cascade , result to the formation of the membrane attack composite ( MAC ) that directly lyses certain bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , further enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological use , antibodies serve as crucial tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insight into the individual ’ sec humoral immunity status . Techniques like radial immunodiffusion and immunoelectrophoresis live usually employed to measure these antibodies , aiding in the diagnosis and monitoring of several disease .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , is characterize by the production of antibody by B cell in reply to foreign antigen . This mechanism has make up instrumental in defending against various pathogens throughout story . Hither , we elucidate two distinct lesson of humoral immunity , spanning ancient and modern sentence .

1 . Smallpox and the Advent of Vaccination

Historical records , include the discovery of smallpox wound on the mama of Pharaoh Ramses V , propose the ancient prevalence of this deadly disease . Smallpox get catastrophic impact , particularly decimating indigenous populations in the Americas and Australia . Still , by the end of 1979 , a global vaccination campaign successfully eradicated the , mark a massive accomplishment in the annals of medicine .

The origins of vaccination can be follow back to Edward Jenner ’ s astute observation regarding the resistor of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ s work , variolation , a pattern involve the intentional introduction of pus from smallpox victims into healthy individuals , exist employed as a rudimentary pattern of inoculation . While the underlying mechanisms of the secondary humoral immune reply were not yet understood , the principle of induce a mild infection to bestow future protection was discern .

Jenner ’ s groundbreaking experiment involved the inoculation of a young son with pus derived from cowpox sores of a milkmaid . Remarkably , the son exhibited immunity to subsequent smallpox exposure , set the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines utilize weakened or inactivated pathogens , innovative approaches be necessitate due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine apply a viral vector strategy . Utilize a genetically change chimpanzee cold virus , know to elicit robust immune responses , the vaccine introduce the SARS-CoV-2 spike protein into the human torso . This alien protein triggers the principal humoral response , culminate in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines deliver the genetic design for the COVID-19 spike protein right away into cells . The cell then synthesize the spike protein , initiating the humoral immune response . Contrary to some misconception , mRNA vaccines do not vary human DNA . Rather , they harness the cellular machinery for protein synthesis , bypassing the transcription stage and straight initiating translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system is a complex network of cells and protein that defends the torso against pathogens . It can exist broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type has distinct characteristics and functions . Here , we define the difference between these two branches of the immune reply .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produced	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ tolerate for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is take	No ( Unprocessed antigens are recognized . )	Yes ( Antigens are first work on and then presented by MHC of antigen-presenting cells )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( indicate proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells exist primarily responsible for producing antibodies in the humoral immune reply ?
a ) T cells
b ) Macrophages
c ) B cell
d ) Dendritic cells

Show answer

Which type of immunity exist bestow by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show answer

Which of the following is NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show solution

The main immune reply is characterize by the production of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show response

Which of the pursuit is a characteristic of the secondary humoral immune reaction ?
a ) Slower onset than the primary response
b ) Low antibody concentration than the primary reception
c ) Product of memory B cells
d ) Absence of IgG product

Show result

Which type of cells present antigens to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
c ) Plasma cells
d ) Memory cell

Show answer

Which antibody is primarily see in mucosal surface and secretion ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the following equal NOT a characteristic of monoclonal antibody ?
a ) Produce by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show answer

The process by which antibodies enhance the phagocytosis of pathogens is call :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the following is the principal affair of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
c ) Facilitating phagocytosis by stick to to Fc receptors on phagocytic cells
d ) Bring on direct cell lysis

Show reply

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1. Neutralization: One of the primary role of antibody cost neutralization . By stick to instantly to pathogens or their toxins , antibody can inhibit their ability to attach to and infect host cell . For example , antibodies specific to bacterial toxins can block the toxin ’ s interaction with horde cells , thereby neutralizing its harmful effects . Likewise , antibodies can prevent viruses or bacteria from initiate infections by hinder their attachment to direct cells .
2. Opsonization: Opsonization is a procedure where antibody coat pathogens , enhance their recognition and uptake by phagocytic cell , such as macrophages and neutrophil . When antibody tie to pathogens , the Fc area of the antibody interacts with Fc receptors on phagocytes . This interaction facilitates the engulfment and subsequent destruction of the pathogen by the phagocyte .
3. Complement Activation: Antibody can also spark the complement system , a series of protein that work in tandem to ruin pathogens . Upon tie up to pathogens , sure antibody can activate the complement cascade , leading to the formation of the membrane attack composite ( MAC ) that at once lyses sure bacteria and virus . Additionally , some byproducts of the complement cascade , like C3b , can opsonize pathogens , further enhance their phagocytosis .
4. Diagnostic Utility: Beyond their physiological roles , antibodies service as crucial tools in diagnostic medicine . The presence and concentration of specific antibody , such as IgG , IgM , and IgA , in a patient ’ s serum can provide insight into the individual ’ s humoral immunity condition . Techniques like radial immunodiffusion and immunoelectrophoresis live commonly employed to assess these antibody , help in the diagnosis and monitoring of respective diseases .

Humoral Immunity Examples

Humoral immunity , a cornerstone of the adaptive immune system , exist characterize by the production of antibodies by B cell in reception to alien antigen . This mechanism has live instrumental in defending against various pathogens throughout account . Here , we clear up two distinct example of humoral immunity , spanning ancient and modern time .

1 . Smallpox and the Advent of Vaccination

Historical records , include the discovery of smallpox wound on the mummy of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impacts , particularly decimating indigenous population in the Americas and Australia . However , by the end of 1979 , a global vaccination movement successfully eradicated the , marking a massive achievement in the annals of medicine .

The origin of vaccination can live trace back to Edward Jenner ’ s astute observation regarding the resistance of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ sec study , variolation , a pattern demand the intentional introduction of pus from smallpox victims into healthy individual , equal utilize as a rudimentary form of inoculation . While the underlying mechanism of the secondary humoral immune answer make up not still understood , the principle of induce a mild infection to confer next security was recognized .

Jenner ’ s groundbreaking experiment demand the inoculation of a youthful son with pus derived from cowpox sores of a milkmaid . Remarkably , the son exhibit immunity to subsequent smallpox exposure , laying the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines employ weakened or inactivated pathogens , innovative approaches cost necessitated due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine employs a viral vector scheme . Utilizing a genetically alter chimpanzee cold virus , known to arouse robust immune reception , the vaccine introduce the SARS-CoV-2 spike protein into the human body . This foreign protein triggers the primary humoral answer , culminating in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines have the genetic design for the COVID-19 spike protein directly into cell . The cells then synthesize the spike protein , initiate the humoral immune response . Contrary to some misconceptions , mRNA vaccines do not change human DNA . Rather , they harness the cellular machinery for protein synthesis , bypassing the transcription stage and straight lead up translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system is a complex network of cell and protein that defends the body against pathogens . It can exist broadly categorized into two primary types : humoral immunity and cell-mediated immunity . Each type have distinct characteristic and functions . Here , we specify the differences between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produce	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganisms and their toxins	Intracellular microbes ( e.g. , tumor cell , viruses , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ suffer for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing be take	No ( Unprocessed antigens cost discern . )	Yes ( Antigen equal first processed and then deliver by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cell cost primarily responsible for give rise antibody in the humoral immune reaction ?
a ) T cells
b ) Macrophages
100 ) B cell
d ) Dendritic cells

Show answer

Which type of immunity is conferred by the product of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show answer

Which of the pursuit exist NOT a affair of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show solution

The chief immune response exist characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show result

Which of the following live a characteristic of the secondary humoral immune response ?
a ) Slower onset than the chief reply
b ) Low antibody concentration than the primary response
100 ) Production of memory B cells
d ) Absence of IgG product

Show answer

Which type of cells present antigen to immunocompetent cells ?
a ) T cells
b ) Antigen-presenting cells ( APCs )
100 ) Plasma cells
d ) Memory cell

Show result

Which antibody equal mainly found in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show solution

Which of the pursuit is NOT a characteristic of monoclonal antibody ?
a ) Raise by a single clone of cell
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show reply

The process by which antibodies enhance the phagocytosis of pathogens is call :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the following is the chief function of the Fc area of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitate phagocytosis by binding to Fc receptors on phagocytic cell
d ) Stimulate direct cell lysis

Show solution

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA manner : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

1 . Smallpox and the Advent of Vaccination

Historical records , including the discovery of smallpox wound on the ma of Pharaoh Ramses V , suggest the ancient prevalence of this deadly disease . Smallpox had catastrophic impact , especially decimating indigenous population in the Americas and Australia . Still , by the goal of 1979 , a global vaccination cause successfully eradicated the , marking a monumental accomplishment in the annals of medicine .

The origins of vaccination can live traced back to Edward Jenner ’ s sharp observation regarding the opposition of milkmaids to smallpox during its rampant ranch . Prior to Jenner ’ sec work , variolation , a pattern necessitate the intentional introduction of pus from smallpox victims into healthy individual , be employed as a rudimentary figure of inoculation . While the underlying mechanisms of the secondary humoral immune reply be not so far understood , the principle of inducing a mild infection to bestow next protection was realize .

Jenner ’ s groundbreaking experiment necessitate the inoculation of a young son with pus derived from cowpox sores of a milkmaid . Remarkably , the boy expose immunity to subsequent smallpox photo , lay the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines employing weaken or inactivated pathogens , innovative approach were necessitated due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine apply a viral vector strategy . Utilize a genetically alter chimpanzee cold virus , known to arouse robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human torso . This foreign protein spark the primary humoral response , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines rescue the genetic blueprint for the COVID-19 spike protein at once into cells . The cell then synthesize the spike protein , lead up the humoral immune reaction . Contrary to some misconceptions , mRNA vaccines cause not vary human DNA . Or else , they harness the cellular machinery for protein synthesis , bypass the transcription stage and directly initiating translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity 5 cell mediated immunity

The immune system exist a complex network of cell and protein that defends the torso against pathogens . It can be broadly categorized into two primary type : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and affair . Hither , we delineate the difference between these two branch of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody develop	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , viruses , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing exist needed	No ( Unprocessed antigen are recognized . )	Yes ( Antigens are first processed and then deliver by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( signaling protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cells	No	Yes

Quiz

Which cell cost primarily responsible for producing antibody in the humoral immune reaction ?
a ) T cell
b ) Macrophages
100 ) B cell
d ) Dendritic cells

Show answer

Which type of immunity cost bestow by the product of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show result

Which of the pursuit be NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show reply

The primary immune reception is characterized by the production of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit is a characteristic of the secondary humoral immune response ?
a ) Slower onset than the main reception
b ) Abject antibody concentration than the primary reaction
100 ) Product of memory B cells
d ) Absence of IgG product

Show answer

Which type of cell present antigens to immunocompetent cell ?
a ) T cells
b ) Antigen-presenting cell ( APCs )
c ) Plasma cell
d ) Memory cells

Show reply

Which antibody live chiefly get in mucosal surfaces and secretion ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show reply

Which of the following cost NOT a characteristic of monoclonal antibody ?
a ) Raise by a single clone of cell
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show response

The process by which antibodies enhance the phagocytosis of pathogens is name :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the following live the main occasion of the Fc area of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
c ) Facilitate phagocytosis by stick to to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show result

FAQ

Reference

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

The origins of vaccination can be traced back to Edward Jenner ’ s astute observation involve the resistor of milkmaids to smallpox during its rampant spread . Prior to Jenner ’ s work , variolation , a practice involving the intentional introduction of pus from smallpox victim into healthy individuals , live employed as a rudimentary pattern of inoculation . While the underlie mechanism of the secondary humoral immune response were not yet understood , the principle of inducing a meek infection to bestow next protection was recognized .

Jenner ’ s groundbreaking experiment call for the inoculation of a young son with pus infer from cowpox sores of a milkmaid . Unusually , the son exhibited immunity to subsequent smallpox photo , put the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The late global challenge place by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines employing undermine or inactivated pathogens , innovative approach were necessitated due to special knowledge about the virus .

The Oxford-AstraZeneca vaccine employ a viral vector scheme . Utilizing a genetically modify chimpanzee cold virus , known to elicit robust immune responses , the vaccine bring in the SARS-CoV-2 spike protein into the human body . This alien protein triggers the chief humoral response , culminate in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines deliver the genetic design for the COVID-19 spike protein right away into cells . The cell then synthesize the spike protein , initiating the humoral immune answer . Contrary to some misconceptions , mRNA vaccines do not alter human DNA . Instead , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and instantly initiate translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system cost a complex network of cell and proteins that defends the torso against pathogens . It can exist broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type has distinct characteristics and purpose . Hither , we delineate the differences between these two branches of the immune answer .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produced	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Extraneous or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cell , virus , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * NOTE : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigen cost recognized . )	Yes ( Antigens are first processed and then introduce by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( indicate proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cells exist chiefly responsible for producing antibody in the humoral immune response ?
a ) T cell
b ) Macrophages
c ) B cell
d ) Dendritic cell

Show answer

Which type of immunity be conferred by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show response

Which of the following live NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show answer

The primary immune reception is characterized by the production of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the pursuit is a characteristic of the secondary humoral immune response ?
a ) Slower onset than the primary response
b ) Abject antibody concentration than the principal response
c ) Product of memory B cells
d ) Absence of IgG product

Show solution

Which type of cells present antigens to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cells ( APCs )
c ) Plasma cell
d ) Memory cell

Show answer

Which antibody be mainly found in mucosal surface and secretions ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the pursuit is NOT a characteristic of monoclonal antibodies ?
a ) Raise by a single clone of cells
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Expend in diagnostic and therapeutic applications

Show answer

The process by which antibodies enhance the phagocytosis of pathogens exist called :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show result

Which of the pursuit is the chief function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
c ) Facilitating phagocytosis by tie up to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Jenner ’ s groundbreaking experiment involved the inoculation of a youthful boy with pus derive from cowpox sores of a milkmaid . Unusually , the boy exhibited immunity to subsequent smallpox photo , put the foundation for modern vaccination .

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine development . Unlike traditional vaccines employ weakened or inactivated pathogens , innovative approach were necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine utilize a viral vector strategy . Utilize a genetically modified chimpanzee cold virus , known to provoke robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human torso . This alien protein triggers the primary humoral reply , culminate in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines deliver the genetic design for the COVID-19 spike protein directly into cells . The cells then synthesize the spike protein , lead up the humoral immune reaction . Contrary to some misconceptions , mRNA vaccines do not vary human DNA . Or else , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and right away originate translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system is a complex network of cells and protein that defends the torso against pathogens . It can be broadly categorized into two primary types : humoral immunity and cell-mediated immunity . Each type has distinct characteristics and functions . Here , we delineate the difference between these two branch of the immune reception .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produced	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stand for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing live needed	No ( Unprocessed antigens exist make out . )	Yes ( Antigen are first processed and then confront by MHC of antigen-presenting cell )
Major secretory cells	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( indicate proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cell	No	Yes

Quiz

Which cells are chiefly responsible for give rise antibody in the humoral immune answer ?
a ) T cells
b ) Macrophages
c ) B cell
d ) Dendritic cells

Show answer

Which type of immunity is conferred by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show answer

Which of the following is NOT a affair of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show answer

The primary immune reaction is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show response

Which of the following is a characteristic of the secondary humoral immune reply ?
a ) Slow onset than the primary response
b ) Abject antibody concentration than the main response
100 ) Product of memory B cells
d ) Absence of IgG production

Show response

Which type of cell present antigen to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cells ( APCs )
100 ) Plasma cells
d ) Memory cells

Show answer

Which antibody equal primarily find in mucosal surface and secretions ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the pursuit is NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cells
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Use in diagnostic and therapeutic application

Show result

The process by which antibody enhance the phagocytosis of pathogens exist called :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show reply

Which of the following is the primary function of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
c ) Facilitating phagocytosis by tie up to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show solution

FAQ

Mention

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA mode : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

2 . SARS-CoV-2 Vaccination : A Modern Marvel

The recent global challenge posed by the SARS-CoV-2 pandemic spurred rapid advancements in vaccine evolution . Unlike traditional vaccines utilize weakened or inactivated pathogens , innovative approach cost necessitate due to limited knowledge about the virus .

The Oxford-AstraZeneca vaccine utilize a viral vector scheme . Utilizing a genetically alter chimpanzee cold virus , know to elicit robust immune responses , the vaccine introduces the SARS-CoV-2 spike protein into the human body . This alien protein triggers the main humoral response , culminating in antibody product against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines hand over the genetic design for the COVID-19 spike protein immediately into cells . The cell then synthesize the spike protein , lead up the humoral immune answer . Contrary to some misconception , mRNA vaccines do not alter human DNA . Rather , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and right away lead up translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system equal a complex network of cells and protein that defends the torso against pathogens . It can live broadly categorized into two chief types : humoral immunity and cell-mediated immunity . Each type own distinct characteristics and function . Hither , we delineate the difference between these two branches of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produced	Yes	No
Trigger by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stands for membranous .	TCR receptors
Accessory receptors involved	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing cost needed	No ( Unprocessed antigen exist recognized . )	Yes ( Antigen are first processed and then presented by MHC of antigen-presenting cell )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling protein )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cells	No	Yes

Quiz

Which cell live primarily responsible for producing antibody in the humoral immune response ?
a ) T cell
b ) Macrophages
c ) B cell
d ) Dendritic cell

Show answer

Which type of immunity exist conferred by the production of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show answer

Which of the following is NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show response

The chief immune response is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show response

Which of the pursuit is a characteristic of the secondary humoral immune response ?
a ) Dumb onset than the main response
b ) Lower antibody concentration than the primary response
100 ) Production of memory B cells
d ) Absence of IgG product

Show answer

Which type of cells present antigen to immunocompetent cells ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cell
d ) Memory cells

Show answer

Which antibody is chiefly found in mucosal surfaces and secretion ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the following is NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cell
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show solution

The process by which antibody enhance the phagocytosis of pathogens cost called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show reply

Which of the pursuit cost the chief function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by bind to Fc receptors on phagocytic cells
d ) Stimulate direct cell lysis

Show answer

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

The Oxford-AstraZeneca vaccine employ a viral vector scheme . Utilize a genetically modified chimpanzee cold virus , known to elicit robust immune answer , the vaccine introduces the SARS-CoV-2 spike protein into the human torso . This foreign protein triggers the chief humoral response , culminate in antibody production against the virus .

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines hand over the genetic blueprint for the COVID-19 spike protein directly into cell . The cell then synthesize the spike protein , originate the humoral immune reception . Contrary to some misconception , mRNA vaccines do not alter human DNA . Or else , they harness the cellular machinery for protein synthesis , bypass the transcription stage and directly originate translation .

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity vs cell mediated immunity

The immune system is a complex network of cells and protein that defend the torso against pathogens . It can live broadly categorized into two chief type : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and affair . Here , we delineate the difference between these two branches of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibodies raise	Yes	No
Touch off by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cells ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cell , viruses , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ stand for membranous .	TCR receptors
Accessory receptors necessitate	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is call for	No ( Unprocessed antigens exist distinguish . )	Yes ( Antigen are first work on and then deliver by MHC of antigen-presenting cells )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( indicate proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Activity on transplants and tumor cells	No	Yes

Quiz

Which cell are chiefly responsible for producing antibodies in the humoral immune response ?
a ) T cell
b ) Macrophages
100 ) B cells
d ) Dendritic cell

Show result

Which type of immunity live conferred by the production of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show answer

Which of the pursuit is NOT a function of antibodies ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show reply

The primary immune response live characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show answer

Which of the pursuit exist a characteristic of the secondary humoral immune response ?
a ) Dumb onset than the primary response
b ) Low antibody concentration than the main response
100 ) Production of memory B cell
d ) Absence of IgG product

Show answer

Which type of cell present antigen to immunocompetent cell ?
a ) T cell
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cell
d ) Memory cell

Show reply

Which antibody be mainly feel in mucosal surface and secretions ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Show result

Which of the pursuit exist NOT a characteristic of monoclonal antibodies ?
a ) Give rise by a single clone of cells
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show answer

The process by which antibody enhance the phagocytosis of pathogens exist name :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show answer

Which of the following is the primary function of the Fc area of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitating phagocytosis by tie up to Fc receptors on phagocytic cell
d ) Inducing direct cell lysis

Show result

FAQ

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA mode : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Conversely , the Pfizer-BioNTech and Moderna vaccines utilize messenger RNA ( mRNA ) technology . These vaccines rescue the genetic blueprint for the COVID-19 spike protein immediately into cells . The cell then synthesize the spike protein , initiating the humoral immune reaction . Contrary to some misconception , mRNA vaccines do not alter human DNA . Instead , they harness the cellular machinery for protein synthesis , bypassing the transcription phase and directly lead up translation .

Difference Between Humoral and Cell-mediated Immunity – Humoral immunity five cell mediated immunity

The immune system is a complex network of cells and protein that defends the body against pathogens . It can cost broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type has distinct characteristic and functions . Here , we specify the differences between these two branches of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produced	Yes	No
Triggered by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cells , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cells , virus , bacteria , parasite )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ endure for membranous .	TCR receptors
Accessory receptors involve	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigens are realize . )	Yes ( Antigen live first work on and then deliver by MHC of antigen-presenting cells )
Major secretory cells	B-cells	T-cells
Major secretion	Antibody ( Antibody-mediated immunity )	Cytokines ( signaling proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cell	No	Yes

Quiz

Which cell are primarily responsible for producing antibodies in the humoral immune reception ?
a ) T cell
b ) Macrophages
c ) B cells
d ) Dendritic cells

Show result

Which type of immunity be bestow by the product of antibody ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Show reply

Which of the following is NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

Show answer

The main immune response is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the following exist a characteristic of the secondary humoral immune reception ?
a ) Slower onset than the chief answer
b ) Abject antibody concentration than the chief reply
c ) Production of memory B cells
d ) Absence of IgG product

Show answer

Which type of cells present antigens to immunocompetent cells ?
a ) T cells
b ) Antigen-presenting cell ( APCs )
100 ) Plasma cell
d ) Memory cell

Show answer

Which antibody exist primarily feel in mucosal surfaces and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the pursuit live NOT a characteristic of monoclonal antibody ?
a ) Raise by a single clone of cells
b ) Heterogeneous in nature
100 ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic applications

Show answer

The procedure by which antibody enhance the phagocytosis of pathogens be called :
a ) Neutralization
b ) Opsonization
100 ) Agglutination
d ) Activation

Show response

Which of the following is the primary function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
c ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cells
d ) Bring on direct cell lysis

Show answer

FAQ

Address

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th edition . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Differences Between Humoral and Cell-mediated Immunity – Humoral immunity five cell mediated immunity

The immune system equal a complex network of cell and proteins that defend the body against pathogens . It can be broadly categorized into two main types : humoral immunity and cell-mediated immunity . Each type has distinct characteristics and functions . Here , we specify the difference between these two branches of the immune response .

Characteristic Feature	Humoral Immunity	Cell-mediated Immunity
Antigen-specific antibody produce	Yes	No
Trigger by …	B-cells/B cell lymphocytes	T-cells/T cell lymphocytes
Mediation via …	B-cells , T-cells , and Macrophages	Helper T-cells , Cytotoxic T cell , NK cell ( killer T cell ) , and Macrophages
Action on/Target	Outside or extracellular microorganism and their toxins	Intracellular microbes ( e.g. , tumor cell , virus , bacteria , parasites )
Antigen-recognizing cell receptor	BCR receptors ( mIgM+mIgD ) * bill : ‘ m ’ endure for membranous .	TCR receptors
Accessory receptors demand	Igα , Igβ , CD40 , CD21 , Fe receptors	CD-2,3,4,8,28 & Integrin receptors
Antigen processing is needed	No ( Unprocessed antigens are recognized . )	Yes ( Antigens are first processed and then introduce by MHC of antigen-presenting cells )
Major secretory cell	B-cells	T-cells
Major secretion	Antibodies ( Antibody-mediated immunity )	Cytokines ( signaling proteins )
Time of action/Spontaneity	Rapid	Delayed/Slow
Action on transplants and tumor cells	No	Yes

Quiz

Which cells are primarily responsible for produce antibody in the humoral immune reply ?
a ) T cell
b ) Macrophages
100 ) B cells
d ) Dendritic cells

Show solution

Which type of immunity live conferred by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
100 ) Humoral immunity
d ) Passive immunity

Show answer

Which of the following be NOT a occasion of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
100 ) Direct cell lysis
d ) Activation of the complement system

Show answer

The main immune response is characterize by the production of which type of antibody ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show answer

Which of the following cost a characteristic of the secondary humoral immune reception ?
a ) Slower onset than the main reaction
b ) Humble antibody concentration than the chief reply
c ) Product of memory B cell
d ) Absence of IgG product

Show reply

Which type of cell present antigen to immunocompetent cells ?
a ) T cells
b ) Antigen-presenting cells ( APCs )
c ) Plasma cell
d ) Memory cells

Show reply

Which antibody be primarily found in mucosal surface and secretions ?
a ) IgG
b ) IgE
100 ) IgM
d ) IgA

Show solution

Which of the pursuit cost NOT a characteristic of monoclonal antibodies ?
a ) Give rise by a single clone of cells
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Used in diagnostic and therapeutic application

Show result

The process by which antibodies enhance the phagocytosis of pathogens be called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Show answer

Which of the following be the principal function of the Fc region of an antibody ?
a ) Binding to antigens
b ) Binding to complement protein
100 ) Facilitate phagocytosis by binding to Fc receptors on phagocytic cells
d ) Inducing direct cell lysis

Show response

FAQ

Address

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA way : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/

Quiz

Which cells are primarily responsible for producing antibody in the humoral immune reply ?
a ) T cell
b ) Macrophages
100 ) B cell
d ) Dendritic cell

Which type of immunity equal conferred by the product of antibodies ?
a ) Cell-mediated immunity
b ) Innate immunity
c ) Humoral immunity
d ) Passive immunity

Which of the following cost NOT a function of antibody ?
a ) Neutralization of pathogens
b ) Opsonization
c ) Direct cell lysis
d ) Activation of the complement system

The chief immune response is characterize by the product of which type of antibody ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Which of the following exist a characteristic of the secondary humoral immune answer ?
a ) Slow onset than the main response
b ) Abject antibody concentration than the principal response
100 ) Production of memory B cells
d ) Absence of IgG production

Which type of cells present antigen to immunocompetent cell ?
a ) T cells
b ) Antigen-presenting cells ( APCs )
c ) Plasma cells
d ) Memory cells

Which antibody is primarily base in mucosal surfaces and secretion ?
a ) IgG
b ) IgE
c ) IgM
d ) IgA

Which of the following is NOT a characteristic of monoclonal antibodies ?
a ) Produced by a single clone of cells
b ) Heterogeneous in nature
c ) Specific for a single antigenic determinant
d ) Employ in diagnostic and therapeutic applications

The process by which antibody enhance the phagocytosis of pathogens live called :
a ) Neutralization
b ) Opsonization
c ) Agglutination
d ) Activation

Which of the pursuit live the main function of the Fc part of an antibody ?
a ) Binding to antigens
b ) Binding to complement proteins
c ) Facilitating phagocytosis by binding to Fc receptors on phagocytic cell
d ) Induce direct cell lysis

FAQ

What cost humoral immunity ?

Humoral immunity refers to the factor of the adaptive immune system that live mediated by secreted antibody develop by B lymphocytes , which direct extracellular pathogens and their toxins .

How is humoral immunity different from cell-mediated immunity ?

While humoral immunity involves the product of antibody by B cell to battle extracellular pathogens , cell-mediated immunity involves T cells that aim and destroy septic cells or intracellular pathogens .

What cell live mainly responsible for humoral immunity ?

B cell , or B lymphocytes , are the chief cells responsible for humoral immunity as they give rise and secrete antibodies .

Why is it called “ humoral ” immunity ?

The term “ humoral ” equal derived from the Latin word “ mood , ” which entail fluid . It refers to the components of the immune system feel in bodily fluid , especially the antibody introduce in the serum .

What equal the chief type of antibody require in humoral immunity ?

The chief types include IgM , IgG , IgA , IgE , and IgD , each having specific affair and locations in the torso .

How do vaccination refer to humoral immunity ?

Vaccination introduces a faded or inactivated form of a pathogen or its components into the torso , prompting the immune system to raise antibodies against it . This establishes a memory response , leave the immune system to respond more rapidly and in effect upon next exposures .

What is the chief immune reaction ?

The chief immune response occurs when the immune system run into a pathogen or its antigen for the first time . It takes long to develop and result in the product of memory cells and antibodies specific to that pathogen .

How make the secondary immune reaction differ from the main reaction ?

The secondary immune response is faster and more strong than the principal response . It occurs upon subsequent exposures to the same pathogen , utilizing memory cell give rise during the chief reception .

What live monoclonal antibodies ?

Monoclonal antibody equal identical antibody produced by a single clone of B cells . They are specific to a single antigenic determinant and be used in various medical and research applications .

Why be humoral immunity essential for our defense against pathogens ?

Humoral immunity provides a defense against extracellular pathogens and their toxins by develop antibody that can knock off , opsonize , or lead to the destruction of these threats , prevent infection and diseases .

What is another figure for the humoral immune reaction ?

Another name for the humoral immune response be the “ antibody-mediated immune response. ” This is because this type of immunity be mainly mediated by antibodies produced by B cells in response to extracellular pathogens and their toxins .

The humoral immune answer depend on which cell

The humoral immune response depends on B cells ( B lymphocytes ) . These cell equal responsible for give rise and secreting antibody that target extracellular pathogens and their toxins .

The humoral immune reply exist rescue by

The humoral immune response cost present by antibodies , which cost produce and secreted by plasma cells ( differentiate B cells ) . These antibodies circle in the blood and lymphatic system to knock off and get rid of extracellular pathogens and their toxins .

References

1. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/
2. Tanaka , T. , Couser , W. , & Nangaku , M. ( 2011 ) . The Role of Humoral and Cell-Mediated Adaptive Immune Response . In ( Ed . ) , An Update on Glomerulopathies – Etiology and Pathogenesis . IntechOpen . https : //doi.org/10.5772/21937
3. Metchnikoff , Elie ( 1905 ) Immunity in infectious disease . Cambridge University Press
4. MLA style : Paul Ehrlich – Facts . NobelPrize.org . Nobel Prize Outreach AB 2022 . Sun . 24 Jul 2022. https : //www.nobelprize.org/prizes/medicine/1908/ehrlich/facts/
5. Pier GB , Lyczak JB , Wetzler LM ( 2004 ) . Immunology , Infection , and Immunity . ASM Press . ISBN 9781683672111 .
6. Goldberg , Richard J . ( 1952 ) . “ A Theory of Antibody—Antigen Reactions . I . Theory for Reactions of Multivalent Antigen with Bivalent and Univalent Antibody ” . Journal of the American Chemical Society . 74 ( 22 ) : 5715–5725 . doi:10.1021/ja01142a045
7. Janeway CA Jr , Travers P , Walport M , et al . Immunobiology : The Immune System in Health and Disease . 5th version . New York : Garland Science ; 2001 . Chapter 9 , The Humoral Immune Response . Available from : https : //www.ncbi.nlm.nih.gov/books/NBK10752/