The document discusses antigen-antibody interactions and various serological techniques used to detect them, including precipitation reactions and agglutination reactions. It describes how antigen and antibody bind through non-covalent interactions, and factors that affect the antigen-antibody reaction like concentration, temperature, and pH. It also summarizes different techniques used to detect antigen-antibody interactions like precipitation, agglutination, Coombs test, and flocculation and the principles behind each method.
Hematopoietic stem cells in the bone marrow can differentiate into various blood cell types, including red blood cells, neutrophils, eosinophils, basophils, mast cells, monocytes/macrophages, dendritic cells, B lymphocytes, T lymphocytes, and natural killer cells. These cells play important roles in immunity, such as phagocytosis of pathogens by neutrophils and macrophages, antibody production by B cells, and cytotoxic killing by natural killer and T cells.
The document summarizes the major immune organs in the body. It describes the primary lymphoid organs of bone marrow and thymus, which support the development of immune cells. It also outlines the secondary lymphoid organs of lymph nodes, spleen, and mucosal-associated lymphoid tissue that trap antigens and allow immune cell interaction. Additionally, it discusses the lymphatic system and how blood and lymph vessels connect the immune organs into a coordinated network.
Antigen is a substance that induces an immune response through the formation of antibodies or activation of T cells. Antigens can be proteins, polysaccharides, nucleic acids, or lipids. Immunogens are antigens that are capable of inducing an immune response on their own due to their large size, while haptens require a carrier molecule. Antigenicity refers to the ability to bind antibodies, while immunogenicity is the ability to induce an immune response. Factors like molecular size, chemical composition, dose, and route of administration can influence a substance's immunogenicity. Adjuvants are substances that enhance the immune response to an immunogen when used together.
Antibodies, also known as immunoglobulins, are Y-shaped proteins produced by B cells in response to antigens. They are composed of four polypeptide chains - two light chains and two heavy chains arranged in a Y shape. The variable regions at the tips of the Y shape give antibodies their ability to bind to specific antigens. The constant regions allow antibodies to activate different immune functions such as complement activation. There are five major classes of antibodies - IgA, IgD, IgE, IgG, and IgM - which have different structures and roles in the immune response.
This document discusses the antigen-antibody reaction. It begins with an introduction that outlines how these reactions form antibody-mediated immunity in the body and help with disease diagnosis and epidemiological surveys in a laboratory setting.
The stages of an antigen-antibody reaction are then described as primary, secondary, and tertiary. The primary stage involves an initial, reversible reaction. Secondary stages result in visible effects like precipitation or agglutination. Tertiary stages can lead to neutralization or destruction of infectious agents.
General features of antigen-antibody reactions are provided, including specificity, the involvement of the entire antigen/antibody molecule, and the formation of a firm but reversible surface combination.
This document discusses antigens and their properties. It defines an antigen as a substance that generates an immune response through antibodies or T cells. Antigens have epitopes that bind to immune cells. Examples of antigens include autoantigens from one's own body, alloantigens from the same species, and heterophile antigens found across species. The document also examines the chemical nature of antigens as mostly proteins and polysaccharides, and properties such as size, degradability, and dose that influence antigenicity. Superantigens are described as antigens that can polyclonally activate a large fraction of T cells. Finally, some common tests for detecting antigens are listed.
This document defines and describes antigens and what makes an effective antigen. It notes that an antigen is any substance that induces an immune response and antibodies specifically bind to antigens. The best antigens are large, complex proteins that are foreign to the host. Characteristics like size, stability, complexity and foreignness influence a substance's ability to act as an antigen. Bacterial proteins, viral capsids and parasitic molecules can all serve as antigens. The document also discusses epitopes, haptens, adjuvants and cross-reactivity in antigen-antibody binding.
This document discusses antigens and epitopes. It defines antigens as substances that induce an immune response and react with immune system products. Antigens include molecules like proteins, polysaccharides, and lipids. Epitopes are specific regions of antigens that interact with antibodies. A single antigen can have multiple epitopes that each bind to a different antibody. Factors that determine antigenicity include size, chemical nature, complexity, structural stability, foreignness, and an individual's genetic makeup.
Hematopoietic stem cells in the bone marrow can differentiate into various blood cell types, including red blood cells, neutrophils, eosinophils, basophils, mast cells, monocytes/macrophages, dendritic cells, B lymphocytes, T lymphocytes, and natural killer cells. These cells play important roles in immunity, such as phagocytosis of pathogens by neutrophils and macrophages, antibody production by B cells, and cytotoxic killing by natural killer and T cells.
The document summarizes the major immune organs in the body. It describes the primary lymphoid organs of bone marrow and thymus, which support the development of immune cells. It also outlines the secondary lymphoid organs of lymph nodes, spleen, and mucosal-associated lymphoid tissue that trap antigens and allow immune cell interaction. Additionally, it discusses the lymphatic system and how blood and lymph vessels connect the immune organs into a coordinated network.
Antigen is a substance that induces an immune response through the formation of antibodies or activation of T cells. Antigens can be proteins, polysaccharides, nucleic acids, or lipids. Immunogens are antigens that are capable of inducing an immune response on their own due to their large size, while haptens require a carrier molecule. Antigenicity refers to the ability to bind antibodies, while immunogenicity is the ability to induce an immune response. Factors like molecular size, chemical composition, dose, and route of administration can influence a substance's immunogenicity. Adjuvants are substances that enhance the immune response to an immunogen when used together.
Antibodies, also known as immunoglobulins, are Y-shaped proteins produced by B cells in response to antigens. They are composed of four polypeptide chains - two light chains and two heavy chains arranged in a Y shape. The variable regions at the tips of the Y shape give antibodies their ability to bind to specific antigens. The constant regions allow antibodies to activate different immune functions such as complement activation. There are five major classes of antibodies - IgA, IgD, IgE, IgG, and IgM - which have different structures and roles in the immune response.
This document discusses the antigen-antibody reaction. It begins with an introduction that outlines how these reactions form antibody-mediated immunity in the body and help with disease diagnosis and epidemiological surveys in a laboratory setting.
The stages of an antigen-antibody reaction are then described as primary, secondary, and tertiary. The primary stage involves an initial, reversible reaction. Secondary stages result in visible effects like precipitation or agglutination. Tertiary stages can lead to neutralization or destruction of infectious agents.
General features of antigen-antibody reactions are provided, including specificity, the involvement of the entire antigen/antibody molecule, and the formation of a firm but reversible surface combination.
This document discusses antigens and their properties. It defines an antigen as a substance that generates an immune response through antibodies or T cells. Antigens have epitopes that bind to immune cells. Examples of antigens include autoantigens from one's own body, alloantigens from the same species, and heterophile antigens found across species. The document also examines the chemical nature of antigens as mostly proteins and polysaccharides, and properties such as size, degradability, and dose that influence antigenicity. Superantigens are described as antigens that can polyclonally activate a large fraction of T cells. Finally, some common tests for detecting antigens are listed.
This document defines and describes antigens and what makes an effective antigen. It notes that an antigen is any substance that induces an immune response and antibodies specifically bind to antigens. The best antigens are large, complex proteins that are foreign to the host. Characteristics like size, stability, complexity and foreignness influence a substance's ability to act as an antigen. Bacterial proteins, viral capsids and parasitic molecules can all serve as antigens. The document also discusses epitopes, haptens, adjuvants and cross-reactivity in antigen-antibody binding.
This document discusses antigens and epitopes. It defines antigens as substances that induce an immune response and react with immune system products. Antigens include molecules like proteins, polysaccharides, and lipids. Epitopes are specific regions of antigens that interact with antibodies. A single antigen can have multiple epitopes that each bind to a different antibody. Factors that determine antigenicity include size, chemical nature, complexity, structural stability, foreignness, and an individual's genetic makeup.
The document provides an overview of immunology topics covered in a course, including the immune system and disease, immunopathology, and therapeutic applications. The course covers basics of the immune system, innate and adaptive immunity, cells and molecules of the immune system, and applications like immunization, transplantation, and immunotherapy. Immunopathology topics include immunodeficiency, autoimmunity, hypersensitivity, and malignancies of the immune system. Therapeutic applications focus on immunization, immunomodulation, transplantation, immunosuppression, and replacement therapies.
Edward Jenner in 1798 discovered that exposure to cowpox provided protection against smallpox in humans, laying the foundation for vaccinations. Louis Pasteur further developed vaccines in the late 1800s by using weakened versions of pathogens to provide immunity. In the early 1900s, scientists such as Metchnikoff and von Behring discovered the cellular and humoral components of the immune system, including phagocytic cells and antibodies. The modern field of immunology was established through breakthroughs including the identification of T and B cells in the 1950s and the discovery that antibodies target specific antigens. Recent work in cancer immunotherapy has focused on inhibiting negative immune regulation to stimulate anti-tumor responses.
The document discusses various serological assays used to detect antibodies and antigens. It describes the basic principles of agglutination tests, precipitation tests, immunofluorescence, radioimmunoassay, ELISA, complement fixation tests, and serum neutralization tests. It provides examples of the application of these assays for diagnosing diseases like brucellosis, influenza, and foot-and-mouth disease. The document emphasizes the importance of assay sensitivity, specificity, reproducibility, and using appropriate antigen and antibody concentrations.
This document provides an overview of antigen-antibody interactions and serological testing. It discusses the specific binding between antigens and antibodies, the formation of immune complexes, and the properties of antigen-antibody reactions including affinity, avidity, cross-reactivity, and specificity. It also describes several types of antigen-antibody reactions like precipitation, agglutination, complement fixation, ELISA, and immunofluorescence. The document is intended to guide students in understanding the basics of antigen-antibody interactions and their applications.
Antigen-Antibody Interactions -
Antigen-antibody interactions depend on four types
of noncovalent interactions: hydrogen bonds, ionic
bonds, hydrophobic interactions, and van der Waals
interactions.
The affinity constant, which can be determined by
Scatchard analysis, provides a quantitative measure of the
strength of the interaction between an epitope of the antigen
and a single binding site of an antibody. The avidity reflects
the overall strength of the interactions between a
multivalent antibody molecule and a multivalent antigen
molecule at multiple sites.
The interaction of a soluble antigen and precipitating antibody
in a liquid or gel medium forms an Ag-Ab precipitate.
Electrophoresis can be combined with precipitation
in gels in a technique called immunoelectrophoresis.
The interaction between a particulate antigen and agglutinating
antibody (agglutinin) produces visible clumping, or
agglutination that forms the basis of simple, rapid, and
sensitive immunoassays.
Radioimmunoassay (RIA) is a highly sensitive and quantitative
procedure that utilizes radioactively labeled antigen
or antibody.
The enzyme-linked immunosorbent assay (ELISA) depends
on an enzyme-substrate reaction that generates a
colored reaction product. ELISA assays that employ
chemiluminescence instead of a chromogenic reaction are
the most sensitive immunoassays available.
In Western blotting, a protein mixture is separated by electrophoresis;
then the protein bands are electrophoretically
transferred onto nitrocellulose and identified with labeled
antibody or labeled antigen.
Fluorescence microscopy using antibodies labeled with
fluorescent molecules can be used to visualize antigen on
or within cells.
Flow cytometry provides an unusually powerful technology
for the quantitative analysis and sorting of cell populations
labeled with one or more fluorescent antibodies.
This document discusses antigen-antibody reactions including factors that affect their measurement and techniques used to measure them in the lab. Key points covered include: affinity and avidity being measures of strength of antigen-antibody binding; specificity and cross-reactivity relating to reaction with single or multiple antigens; and techniques including precipitation tests, agglutination, ELISA, radioimmunoassay, immunofluorescence, and complement fixation. Both qualitative and quantitative applications are discussed.
The document discusses various properties of antigens that determine their antigenicity including molecular size, foreignness, chemical complexity, stability, and more. It also describes different types of antigenic determinants recognized by B cells and T cells as well as factors like dosage, route of administration, and adjuvants that influence immunogenicity. Finally, it covers antigen specificity and different types of antigens such as haptens, superantigens, and isoantigens.
Immunologic methods are used in the laboratory diagnosis of infections by detecting the interaction between antigens and antibodies. Common techniques include agglutination, immunofluorescence, ELISA, and immunoblotting. Agglutination involves clumping of antigens by antibodies that can be seen visually. Immunofluorescence uses antibodies coupled to fluorescent dyes to identify antigens under UV light. ELISA detects antigens or antibodies through an enzymatic reaction, while immunoblotting confirms antibody presence by blotting proteins and detecting binding. These methods exploit the high specificity of the antigen-antibody reaction for diagnostic purposes.
Antigen antibody interactions play important role in immunological assays which help in detection of disease.Such interaction are of various types e.g.Precipitation,Flocculation, Agglutination, Complement fixation, ELISA,RIA, Immunoflourescence,Immunoprecipitation.
Antigens are substances that stimulate the immune system to produce antibodies against them. They enter the body through various sites and are then captured and presented by antigen presenting cells. There are several types of antigens including immunogens, which induce immune responses; tolerogens, which induce tolerance; allergens; and vaccines. An antigen's ability to induce an immune response is called its immunogenicity, while its ability to bind antibodies is its antigenicity. Properties that influence immunogenicity include the antigen's foreignness, size, complexity, degradability, and the recipient's genotype and age. Administration methods like dosage, route, and use of adjuvants can also impact immunogenicity. Antigens are classified as complete if they have
Immune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to substances or tissue that have the capacity to elicit an immune response in a given organism. Immune tolerance is important for normal physiology. Central tolerance is the main way the immune system learns to discriminate self from non-self. Peripheral tolerance is key to preventing over-reactivity of the immune system to various environmental entities (allergens, gut microbes, etc.).
The document discusses antigens, which are mostly proteins or polysaccharides from foreign organisms that elicit an immune response. Antigens can come from microbes like bacteria or viruses, or be non-microbial in origin like pollen or transplanted tissues. They must have a molecular weight over 10,000 or be coupled to a carrier molecule to be recognized. Antigens have properties like their chemical composition, molecular weight, and ability to be processed. There are two main types of antigens: exogenous antigens from outside the body and endogenous antigens from within the body. Epitopes are small parts of antigens that specifically interact with antibodies.
The document discusses immunity and the immune system. It describes the three lines of defense against microorganisms as intact skin/mucus membranes, the innate immune system, and the acquired immune system. The acquired system has both cell-mediated and antibody-mediated immunity. Key cells involved include T cells, B cells, macrophages, neutrophils, and natural killer cells. The adaptive response has memory and specificity. Both innate and adaptive immunity provide protection through cells and proteins like antibodies and cytokines.
1) Affinity refers to the strength of binding between a single antigenic site and antibody binding site, while avidity refers to the overall strength of binding between multivalent antigens and antibodies.
2) Avidity is influenced by both affinity and the valence (number of binding sites) of the antigen and antibody. More binding sites results in higher avidity.
3) Specificity refers to an antibody only binding to one antigen, while cross-reactivity is binding to multiple antigens that share similar epitopes.
This document provides an introduction to immunology. It defines immunology as the study of the immune system and its functions in health and disease. The immune system recognizes, attacks, and remembers pathogens that enter the body using innate and adaptive defenses. Key events in immunology history are described, such as Edward Jenner's discovery of vaccination and the eradication of smallpox. Components of the immune system like antibodies, lymphocytes, and the complement system are introduced. The document also distinguishes between innate immunity, which provides non-specific defenses, and adaptive immunity, which has memory and specificity.
what is innate immunity, its mechanism, principal, diagrams, features of innate immunity, factors affecting innate immunity, mechanism described by the help of diagrams and also the different barriers of innate immunity.
This document provides an overview of antigen-antibody reactions, including definitions, general features, measurement techniques, types of reactions such as precipitation, agglutination, neutralization, immunofluorescence, radioimmunoassay, and enzyme-linked immunosorbent assay (ELISA). It describes techniques like precipitation reactions in liquids and gels, single and double diffusion, electrophoresis, latex agglutination, complement fixation, and microtitration agglutination tests. The document outlines the applications and uses of these various antigen-antibody reaction techniques.
This document provides an overview of immunology and some key figures in its history. It begins by explaining that immunology started as a branch of microbiology focused on the study of disease and the immune system's response to antigens. The document then defines immunology as the study of the immune system, which protects the body from infection. It describes the roles of immunologists as scientists who research the immune system in laboratories and clinics. Several pioneering researchers are highlighted, including Anton van Leeuwenhoek, considered the "Father of Microbiology", for his early microscopic observations. Edward Jenner developed the smallpox vaccine in the late 18th century. Later figures like Louis Pasteur, Paul Ehrlich, and Robert Koch made
This document describes the four types of hypersensitivity reactions classified by Coombs and Gell. Type I reactions are immediate and mediated by IgE antibodies. Type II reactions are antibody-dependent and involve antibodies binding to antigens on a person's own cells. Type III reactions involve immune complex formation and deposition in tissues. Type IV reactions are cell-mediated and delayed, involving T lymphocytes and occurring 2-3 days after antigen exposure. Examples of each type are provided along with descriptions of mechanisms and diagnostic approaches.
in vitro antigen -antibody reaction (1).pptxssuser3c47e3
This document provides an overview of in-vitro antigen-antibody reactions other than solid phase immunoassays. It describes the basics of antigen-antibody reactions including formation of immune complexes. It also discusses various types of antigen-antibody reactions like precipitation, agglutination, complement fixation and neutralization. Specific techniques like precipitation reactions in liquids and gels, immunodiffusion, immunoelectrophoresis, counter-current immunoelectrophoresis and rocket electrophoresis are summarized.
The document provides an overview of immunology topics covered in a course, including the immune system and disease, immunopathology, and therapeutic applications. The course covers basics of the immune system, innate and adaptive immunity, cells and molecules of the immune system, and applications like immunization, transplantation, and immunotherapy. Immunopathology topics include immunodeficiency, autoimmunity, hypersensitivity, and malignancies of the immune system. Therapeutic applications focus on immunization, immunomodulation, transplantation, immunosuppression, and replacement therapies.
Edward Jenner in 1798 discovered that exposure to cowpox provided protection against smallpox in humans, laying the foundation for vaccinations. Louis Pasteur further developed vaccines in the late 1800s by using weakened versions of pathogens to provide immunity. In the early 1900s, scientists such as Metchnikoff and von Behring discovered the cellular and humoral components of the immune system, including phagocytic cells and antibodies. The modern field of immunology was established through breakthroughs including the identification of T and B cells in the 1950s and the discovery that antibodies target specific antigens. Recent work in cancer immunotherapy has focused on inhibiting negative immune regulation to stimulate anti-tumor responses.
The document discusses various serological assays used to detect antibodies and antigens. It describes the basic principles of agglutination tests, precipitation tests, immunofluorescence, radioimmunoassay, ELISA, complement fixation tests, and serum neutralization tests. It provides examples of the application of these assays for diagnosing diseases like brucellosis, influenza, and foot-and-mouth disease. The document emphasizes the importance of assay sensitivity, specificity, reproducibility, and using appropriate antigen and antibody concentrations.
This document provides an overview of antigen-antibody interactions and serological testing. It discusses the specific binding between antigens and antibodies, the formation of immune complexes, and the properties of antigen-antibody reactions including affinity, avidity, cross-reactivity, and specificity. It also describes several types of antigen-antibody reactions like precipitation, agglutination, complement fixation, ELISA, and immunofluorescence. The document is intended to guide students in understanding the basics of antigen-antibody interactions and their applications.
Antigen-Antibody Interactions -
Antigen-antibody interactions depend on four types
of noncovalent interactions: hydrogen bonds, ionic
bonds, hydrophobic interactions, and van der Waals
interactions.
The affinity constant, which can be determined by
Scatchard analysis, provides a quantitative measure of the
strength of the interaction between an epitope of the antigen
and a single binding site of an antibody. The avidity reflects
the overall strength of the interactions between a
multivalent antibody molecule and a multivalent antigen
molecule at multiple sites.
The interaction of a soluble antigen and precipitating antibody
in a liquid or gel medium forms an Ag-Ab precipitate.
Electrophoresis can be combined with precipitation
in gels in a technique called immunoelectrophoresis.
The interaction between a particulate antigen and agglutinating
antibody (agglutinin) produces visible clumping, or
agglutination that forms the basis of simple, rapid, and
sensitive immunoassays.
Radioimmunoassay (RIA) is a highly sensitive and quantitative
procedure that utilizes radioactively labeled antigen
or antibody.
The enzyme-linked immunosorbent assay (ELISA) depends
on an enzyme-substrate reaction that generates a
colored reaction product. ELISA assays that employ
chemiluminescence instead of a chromogenic reaction are
the most sensitive immunoassays available.
In Western blotting, a protein mixture is separated by electrophoresis;
then the protein bands are electrophoretically
transferred onto nitrocellulose and identified with labeled
antibody or labeled antigen.
Fluorescence microscopy using antibodies labeled with
fluorescent molecules can be used to visualize antigen on
or within cells.
Flow cytometry provides an unusually powerful technology
for the quantitative analysis and sorting of cell populations
labeled with one or more fluorescent antibodies.
This document discusses antigen-antibody reactions including factors that affect their measurement and techniques used to measure them in the lab. Key points covered include: affinity and avidity being measures of strength of antigen-antibody binding; specificity and cross-reactivity relating to reaction with single or multiple antigens; and techniques including precipitation tests, agglutination, ELISA, radioimmunoassay, immunofluorescence, and complement fixation. Both qualitative and quantitative applications are discussed.
The document discusses various properties of antigens that determine their antigenicity including molecular size, foreignness, chemical complexity, stability, and more. It also describes different types of antigenic determinants recognized by B cells and T cells as well as factors like dosage, route of administration, and adjuvants that influence immunogenicity. Finally, it covers antigen specificity and different types of antigens such as haptens, superantigens, and isoantigens.
Immunologic methods are used in the laboratory diagnosis of infections by detecting the interaction between antigens and antibodies. Common techniques include agglutination, immunofluorescence, ELISA, and immunoblotting. Agglutination involves clumping of antigens by antibodies that can be seen visually. Immunofluorescence uses antibodies coupled to fluorescent dyes to identify antigens under UV light. ELISA detects antigens or antibodies through an enzymatic reaction, while immunoblotting confirms antibody presence by blotting proteins and detecting binding. These methods exploit the high specificity of the antigen-antibody reaction for diagnostic purposes.
Antigen antibody interactions play important role in immunological assays which help in detection of disease.Such interaction are of various types e.g.Precipitation,Flocculation, Agglutination, Complement fixation, ELISA,RIA, Immunoflourescence,Immunoprecipitation.
Antigens are substances that stimulate the immune system to produce antibodies against them. They enter the body through various sites and are then captured and presented by antigen presenting cells. There are several types of antigens including immunogens, which induce immune responses; tolerogens, which induce tolerance; allergens; and vaccines. An antigen's ability to induce an immune response is called its immunogenicity, while its ability to bind antibodies is its antigenicity. Properties that influence immunogenicity include the antigen's foreignness, size, complexity, degradability, and the recipient's genotype and age. Administration methods like dosage, route, and use of adjuvants can also impact immunogenicity. Antigens are classified as complete if they have
Immune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to substances or tissue that have the capacity to elicit an immune response in a given organism. Immune tolerance is important for normal physiology. Central tolerance is the main way the immune system learns to discriminate self from non-self. Peripheral tolerance is key to preventing over-reactivity of the immune system to various environmental entities (allergens, gut microbes, etc.).
The document discusses antigens, which are mostly proteins or polysaccharides from foreign organisms that elicit an immune response. Antigens can come from microbes like bacteria or viruses, or be non-microbial in origin like pollen or transplanted tissues. They must have a molecular weight over 10,000 or be coupled to a carrier molecule to be recognized. Antigens have properties like their chemical composition, molecular weight, and ability to be processed. There are two main types of antigens: exogenous antigens from outside the body and endogenous antigens from within the body. Epitopes are small parts of antigens that specifically interact with antibodies.
The document discusses immunity and the immune system. It describes the three lines of defense against microorganisms as intact skin/mucus membranes, the innate immune system, and the acquired immune system. The acquired system has both cell-mediated and antibody-mediated immunity. Key cells involved include T cells, B cells, macrophages, neutrophils, and natural killer cells. The adaptive response has memory and specificity. Both innate and adaptive immunity provide protection through cells and proteins like antibodies and cytokines.
1) Affinity refers to the strength of binding between a single antigenic site and antibody binding site, while avidity refers to the overall strength of binding between multivalent antigens and antibodies.
2) Avidity is influenced by both affinity and the valence (number of binding sites) of the antigen and antibody. More binding sites results in higher avidity.
3) Specificity refers to an antibody only binding to one antigen, while cross-reactivity is binding to multiple antigens that share similar epitopes.
This document provides an introduction to immunology. It defines immunology as the study of the immune system and its functions in health and disease. The immune system recognizes, attacks, and remembers pathogens that enter the body using innate and adaptive defenses. Key events in immunology history are described, such as Edward Jenner's discovery of vaccination and the eradication of smallpox. Components of the immune system like antibodies, lymphocytes, and the complement system are introduced. The document also distinguishes between innate immunity, which provides non-specific defenses, and adaptive immunity, which has memory and specificity.
what is innate immunity, its mechanism, principal, diagrams, features of innate immunity, factors affecting innate immunity, mechanism described by the help of diagrams and also the different barriers of innate immunity.
This document provides an overview of antigen-antibody reactions, including definitions, general features, measurement techniques, types of reactions such as precipitation, agglutination, neutralization, immunofluorescence, radioimmunoassay, and enzyme-linked immunosorbent assay (ELISA). It describes techniques like precipitation reactions in liquids and gels, single and double diffusion, electrophoresis, latex agglutination, complement fixation, and microtitration agglutination tests. The document outlines the applications and uses of these various antigen-antibody reaction techniques.
This document provides an overview of immunology and some key figures in its history. It begins by explaining that immunology started as a branch of microbiology focused on the study of disease and the immune system's response to antigens. The document then defines immunology as the study of the immune system, which protects the body from infection. It describes the roles of immunologists as scientists who research the immune system in laboratories and clinics. Several pioneering researchers are highlighted, including Anton van Leeuwenhoek, considered the "Father of Microbiology", for his early microscopic observations. Edward Jenner developed the smallpox vaccine in the late 18th century. Later figures like Louis Pasteur, Paul Ehrlich, and Robert Koch made
This document describes the four types of hypersensitivity reactions classified by Coombs and Gell. Type I reactions are immediate and mediated by IgE antibodies. Type II reactions are antibody-dependent and involve antibodies binding to antigens on a person's own cells. Type III reactions involve immune complex formation and deposition in tissues. Type IV reactions are cell-mediated and delayed, involving T lymphocytes and occurring 2-3 days after antigen exposure. Examples of each type are provided along with descriptions of mechanisms and diagnostic approaches.
in vitro antigen -antibody reaction (1).pptxssuser3c47e3
This document provides an overview of in-vitro antigen-antibody reactions other than solid phase immunoassays. It describes the basics of antigen-antibody reactions including formation of immune complexes. It also discusses various types of antigen-antibody reactions like precipitation, agglutination, complement fixation and neutralization. Specific techniques like precipitation reactions in liquids and gels, immunodiffusion, immunoelectrophoresis, counter-current immunoelectrophoresis and rocket electrophoresis are summarized.
The antigen-antibody reaction is a reversible binding between antigens and antibodies that is highly specific. This interaction is essential for protecting organisms from pathogens. The reaction involves non-covalent bonds between epitopes on antigens and paratopes on antibodies, forming a lock-and-key arrangement. Affinity refers to the strength of binding between a single antigen site and antibody site, while avidity describes the strength of binding between multivalent antigens and antibodies. Antigen-antibody interactions can be detected through precipitation, agglutination, or other reactions and play an important role in the immune response.
The document discusses antigen-antibody reactions. It begins by introducing antigens and antibodies and how they specifically combine in antigen-antibody reactions. The reactions occur in three stages: formation of an antigen-antibody complex, leading to visible events like precipitation or agglutination, and destruction or neutralization of the antigen. Key features of antigen-antibody reactions are their specificity, the formation of immune complexes, antigen binding sites called epitopes, and the binding force between antigens and antibodies. Common types of antigen-antibody reactions include precipitation, agglutination, complement fixation, ELISA, and immunofluorescence.
Types of immunoprecipitation reactions, heterogeneous and homogeneous immunoassays methods, immunoelectrophoresis, categories of immunoassay, ELISA, types of ELISA, competitive and noncompetitive assay
Antigen-antibody interactions can be quantified using various serological tests. Common types include precipitation tests like immunodiffusion that form visible precipitate lines, agglutination tests where antigens clump together, neutralization tests using viruses and complement fixation assays. Enzyme-linked immunosorbent assays (ELISAs) are now widely used as they are sensitive, specific and can be quantitative or qualitative. Fluorescent antibody techniques use fluorescent dyes to label antibodies or cells for detection under a microscope.
The document discusses antigen-antibody reactions. It describes how antigens interact specifically with antibodies produced against them, forming antigen-antibody complexes. The complexes can then undergo precipitation, agglutination, complement fixation, or cytolysis depending on whether the antigen is soluble or insoluble. It also discusses the properties, types, techniques and applications of common antigen-antibody reactions like precipitation, agglutination, complement fixation tests and opsonization.
This document discusses antigen-antibody reactions, including their specificity, the formation of immune complexes, and the non-covalent bonds involved in binding. It describes different types of antigen-antibody reactions like precipitation, agglutination, complement fixation, ELISA, and immunofluorescence. It also outlines applications like blood typing, disease detection, immunoassays, and assessing immune deficiencies.
The document summarizes antigen-antibody reactions. It describes how antigens stimulate the production of antibodies. There are three main stages to antigen-antibody reactions: interaction without visible effects, formation of visible precipitates or agglutination, and neutralization or destruction of antigens. The document also discusses immune complexes, specificity, binding sites, forces, properties, types of reactions including precipitation, agglutination, and applications of these reactions in diagnosing diseases.
1) Agglutination tests detect antigens or antibodies by exploiting the ability of antibodies to cross-link antigen-coated particles, forming visible clumps or lattices.
2) There are several types of agglutination tests including direct, passive, and reverse passive agglutination as well as hemagglutination and hemagglutination inhibition.
3) Agglutination tests are useful, rapid techniques for detecting various infectious diseases and other analytes but can be limited by prozone effects at high antibody concentrations.
The document discusses various antigen-antibody reactions including precipitation, agglutination, neutralization, complement fixation, immunofluorescence, radioimmunoassay, enzyme immunoassay, and immunoblotting. It describes how these reactions work, their applications in laboratory testing and research, and factors like sensitivity and specificity. Key stages of antigen-antibody interactions like primary, secondary and tertiary are also outlined.
This document discusses antigen-antibody precipitation reactions and double immunodiffusion techniques. Precipitation occurs when soluble antigen and antibody combine to form insoluble complexes called precipitins. Double immunodiffusion, or the Ouchterlony technique, involves placing antigen and antibody samples in wells in an agar plate where they diffuse and form visible precipitation lines if they react. The pattern of lines can indicate if antigens are identical, partially identical, or unrelated. This technique is used to detect, identify, and compare antigens for applications like disease diagnosis.
The document discusses antigen-antibody reactions, including:
- Antigens and antibodies bind specifically to each other, forming antigen-antibody complexes.
- Antigen-antibody reactions include precipitation, agglutination, complement fixation, ELISA, and immunofluorescence.
- These reactions have various applications, including blood typing for transfusions, detecting infectious disease exposure, and developing immunoassays.
This document discusses antigen-antibody reactions, including:
1. Antigen-antibody reactions can occur in two stages - a primary reversible reaction and a secondary reaction that leads to observable effects like precipitation or agglutination.
2. The strength of antigen-antibody binding depends on affinity between individual binding sites and avidity from multiple bonds.
3. Various serological tests like precipitation, agglutination, immunoassays rely on detecting antigen-antibody lattice formations or complexes to indicate the presence of either antigen or antibody.
Ag-Ab-Reactions.pdf microbiology and botanyjyothisaisri
The document discusses antigen-antibody reactions, including the specific and reversible binding between antigens and antibodies. It describes the properties of antigen-antibody reactions, such as high specificity, non-covalent interactions, and reversibility. It also discusses the concepts of affinity, avidity, and cross-reactivity. Finally, it summarizes several types of antigen-antibody reactions: precipitation, agglutination, complement fixation, and neutralization.
This document provides an overview of antigen-antibody reactions including their general properties, types of reactions, and evaluation of immunoassays. It describes various conventional techniques such as precipitation reactions, agglutination reactions, and complement fixation tests. It also summarizes newer techniques like enzyme-linked immunosorbent assay (ELISA), enzyme-linked fluorescent assay (ELFA), radioimmunoassay (RIA), and chemiluminescence-linked immunoassay (CLIA). The document aims to help students understand antigen-antibody reactions and their applications in diagnostic testing.
The document discusses antigen-antibody reactions. It describes how antibodies bind specifically to antigens via non-covalent interactions between the antigen's epitope and the antibody's variable region. This specificity allows immunoassays to detect antibodies or antigens for disease diagnosis, immune response monitoring, and identifying molecules of interest. Different types of antigen-antibody reactions are precipitation reactions, agglutination reactions, complement fixation, ELISA, and immunofluorescence which are used in various applications like blood typing, disease diagnosis, and quantification of substances.
This document discusses various immunotechniques used to detect antigens and antibodies, including primary and secondary interactions, precipitation reactions, agglutination tests, radioimmunoassay, ELISA, and Western blotting. Primary interactions involve immune complex formation between antigens and antibodies via non-covalent bonds. Secondary interactions include precipitation, which can be measured via precipitation curves in solution or immunodiffusion/immunoelectrophoresis in gels. Radioimmunoassay and ELISA allow sensitive detection of antigens and antibodies using radioactive or enzyme labels. Western blotting identifies specific proteins separated by electrophoresis.
1. Antigen-antibody reactions occur when antigens and antibodies come into contact, such as when foreign substances enter the body.
2. These reactions are characterized by non-covalent bonds between the antigen and antibody, including hydrogen bonds, electrostatic bonds, hydrophobic bonds, and Van der Waals forces.
3. Consequences of antigen-antibody reactions include opsonization, activation of immune cells through Fc receptors, complement activation, and neutralization of pathogens or toxins.
This document provides an overview of immunological laboratory techniques used to detect antigens and antibodies. It describes common assays such as precipitation reactions, agglutination tests, enzyme-linked immunosorbent assays (ELISAs), fluorescent activated cell sorting, immunoblotting, and antibody microarrays. Specific techniques covered include radial immunodiffusion, double immunodiffusion, immunoelectrophoresis, haemagglutination, haemagglutination inhibition, indirect ELISA, sandwich ELISA, competitive ELISA, and enzyme-linked immunospot (ELISPOT) assays. The document explains the principles, applications, and interpretations of these important immunological methods.
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
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The cost of acquiring information by natural selectionCarl Bergstrom
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
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Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdfSelcen Ozturkcan
Ozturkcan, S., Berndt, A., & Angelakis, A. (2024). Mending clothing to support sustainable fashion. Presented at the 31st Annual Conference by the Consortium for International Marketing Research (CIMaR), 10-13 Jun 2024, University of Gävle, Sweden.
2. INTRODUCTION
• It is association between an antibody and an antigen by noncovalent
interactions between the antigenic determinant (epitope) of the
antigen and the variable-region (VH/VL) domain of the antibody
molecule (CDRs).
• The non covalent forces that hold the reactants (Ag-Ab) together
are:
1. van der Waals forces
2. Electrostatic forces
3. Hydrophobic forces
4. Hydrogen bonds
5. Ionic bonds
• It can be used to detect the presence of either antibody or antigen.
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4. FACTORS AFFECTS ANTIGEN-
ANTIBODY REACTION
• Concentrations of reactants
• Temperature
• Length of incubation
• pH of test system
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5. PHASES OF ANTIGEN/ANTIBODY
REACTIONS
1. Primary Phenomenon: Sensitization – binding of antibody to antigen
(not visible). These tests are Difficult, Complex, Expensive, Require
special equipment and Time consuming. Primary Phenomenon Based
Techniques include: Immunofluorescence, Radioimmunoassay,
Enzyme immunoassay
2. Secondary Phenomenon: Lattice formation - Sensitization taken a
step further to lattice formation. Fab of Antibody molecule binds to
two separate antigens on adjacent antigens: If antigen on large
structures such as RBCs causes agglutination and if both antibody
and antigen are soluble results in precipitation. These tests are easy
to perform, less expensive, less time consuming and do not require
special equipment. Secondary Phenomenon Based Techniques
include: Precipitation, Agglutination and Complement Fixation
3. Tertiary Phenomenon: Reaction not visible, detected by affect of
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6. SOME TERMINOLOGIES
1. Affinity: Measure of the binding strength between an
antigenic determinant (epitope) and an antibody combining
site. It is the sum of the attractive and repulsive forces
operating between the antigenic determinant and the
combining site .
2. Avidity: The cumulative binding strength of all antibody-
epitope pairs which results from multivalent antigen and
antibody.
3. Cross-Reactivity: It is reaction between an antibody and
an antigen that differs from the immunogen. It is sometimes
also referred to as crossimmunity or cross-protective
immunity.
4. Valence: The relative capability of a antibody to react with a
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7. PROZONE EFFECT OR HOOK
EFFECT
• Hook effect or the prozone effect is an immunologic
phenomenon whereby the effectiveness of antibodies to form
immune complexes is sometimes impaired when
concentrations of an antibody or an antigen are very high.
• The formation of immune complexes stops increasing with
greater concentrations and then decreases with extremely high
concentrations, producing a hook shape on a graph of
measurements.
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8. PRECIPITATION REACTIONS
One of the easiest of serological tests
Soluble Ag & Ab interact and form a lattice
that develops into a visible precipitate.
Occur best when antigen and antibody are
present in optimal proportions (Equivelance).
Antibodies that aggregate soluble antigens
are called precipitins.
Polyclonal antibodies can form lattices, or
large aggregates and monoclonal antibody
can link only two molecules of antigen and no
precipitate is formed.
( Lattices or large
aggregates )
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9. PRECIPITATION CURVE
Plots of the amount Ag/Ab complexes precipitated when
increasing Ag concentrations are added to constant
concentration of Ab. It reveals 3 zones:
1. Zone of antibody excess - precipitation is inhibited and
antibody not bound to antigen can be detected in the
supernatant;
2. Zone equivalence - maximal precipitation in which antibody
and antigen form large insoluble complexes and neither
antibody nor antigen can be detected in the supernatant;
3. Zone of antigen excess - precipitation is inhibited & Ag. not
bound to Ab. can be detected in the supernatant
3/22/2021 9
11. TYPES OF PRECIPITATION
REACTION
I- Precipitation in Solution
a) Bottom Precipitate
b) Ring Precipitate (Ring Test)
II- Simple Immunodiffusion
(ID) or precipitation in gel
a) Double ID (Ouchterlony or
ODD)
b) Single Radial ID (RID)
(Mancini)
III- Electro-Immnodiffusion
a) Immunoelectrophoresis (IEP)
b) Immunofixation
c) Rocket Electroimmunodiffusion (EID)
d) Counterimmunoelectrophoresis (CIEP)
IV-Measurement of Precipitation by Light
a) Turbidimetry
b) Nephelometry
3/22/2021 11
12. ADVANTAGES & DISADVANTAGES OF
PRECIPITATION
Disadvantages
1. Time consuming
2. Some costly instruments
are required
3. High technical skill
required
Advantages:
1. Fairly sensitive
2. High specificity
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13. PRECIPITATION REACTION IN FLUID
Precipitation reactions in fluids follow
the same roles of precipitation curve
zones.
A. Bottom Precipitate: Occurs when
Soluble Ag interact with soluble Ab
and form a visible precipitate that
give bottom ppt after centrifugation.
B. Ring Precipitate (Ring Test) (Tube
Precipitation test): Involve soluble
antigens with antibodies in tubes (test
or Capillary tubes). Layer Ag over Ab
Precipitate occurs at the interface of
the two reagents, forming a ring. It is
Test Tube
reaction
3/22/2021 13
14. PRECIPITATION REACTION IN GEL
•Agar gel used as medium.
•The precipitate is seen in gels as visible
precipitin lines.
a) Single Radial ID
• The technique is quantitative is based
upon the reaction between an Ag, and a
specific Ab during a diffusion period.
• Ag placed in a well diffuses into an agar
containing the Ab (anti-IgG looking for
serum IgG).
• The Ag-Ab interaction is manifested by a
well-defined ring of precipitation around
the Ag well.
The region of equivalence
3/22/2021 14
15. PRECIPITATION REACTION IN GEL
b) Double Radial ID (Ouchterlony or ODD)
• Both antigen and antibody can diffuse
independently.
• It is based upon the simultaneous
application of Ag and Ab in separate but
adjacent wells of an agar plate.
• As the materials diffuse toward one
another, precipitate lines form resulting
from the Ag-Ab interactions.
The region of equivalenc
3/22/2021 15
16. If multiple wells of Ag are positioned around an Ab well on the
same plate, several patterns of reactivity may be observed.
3/22/2021 16
17. If the Ag A (patient)
is the same as the Ag
A (control), the
reaction with the Ab
will be the same and
the result is a solid,
continuous, smooth
line of identity
between the Ag wells
and the Ab well.
If Ag A (patient) is
different from Ag B
(control), and both
react with the Abs to
A & B, the precipitin
lines cross and a
double spur is
formed; this is a line
of nonidentity.
If Ag A (patient) and
Ag A1 (control) share
a common element
but are not exactly the
same (Abs to A), a
single spur is formed.
This is the line of
partial identity.
3/22/2021 17
18. MEASUREMENT OF
PRECIPITATION BY LIGHT
Principle : Antigen-antibody complexes, when formed, will precipitate
in a solution resulting in a turbid or cloudy appearance that can be
measured by:
1. Turbidimetry: Passing light through a cloudy solution (Net
decrease in light intensity).
2. Nephelometry: Measuring light scattered at a particular angle after
being passed through a solution i.e. indirect measure. Amount of
light scattered correlates to the concentration of the solution
Evaluation: Ag concentration is proportional to the turbidity of
complexes.
• It is used for the measurement of serum proteins concentration
(immunoglobulins, acute-phase proteins, complement components
C3, C4, transferrin, albumin etc.).
3/22/2021 18
19. AGGLUTINATION REACTIONS
Interaction between Ab & Particulate Ag results in visible clumping called
Agglutination.
When antibodies are mixed with their corresponding antigens on the
surface of large, easily sedimented particles such as animal cells,
erythrocytes, or bacteria, the antibodies cross-link the particles, forming
visible clumps. This reaction is termed agglutination.
Antibodies produces such reactions are called agglutinins.
It depends on cross linking of polyvalent antigens.
Occur best when antigen and antibody are present in optimal proportions
(Equivelance).
Types of particles that participate in such reactions are erythrocytes,
bacterial cells and inert carriers such as latex particles. Each particle must
have multiple antigenic or determinant sites, which are cross-linked to
3/22/2021 19
21. ADVANTAGES AND DISADVANTAGES OF
AGGLUTINATION
Advantages:
•Most widely used
•Very simple
•No instrument required
•Cheap
•Sensitive
Disadvantages:
•No highly specificity
•No highly sensitivity
3/22/2021 21
22. HEMAGGLUTINATION
• It is a type of direct agglutination reaction.
• When antibodies bind antigens on the
surface of red blood cells (RBCs), the
resultant clumping reaction is referred to
as hemagglutination.
• E.g.: Typing of ABO antigen.
• RBCs are mixed on a slide with antisera to
the A or B blood group antigens. If the
antigen is present on the cells, they
agglutinate, forming a visible clumps on
the slide.
• Determination of which Ag are present on
donor and recipient RBCs is the basis for
matching blood types for transfusion.
3/22/2021 22
23. BACTERIAL AGGLUTINATION
• It is a type of direct agglutination reaction.
• A bacterial infection give rise to the production of serum antibodies
specific for bacterial surface antigen which can be detected by bacterial
agglutination tests.
• It may be qualitative (Slide test) or quantitative (Tube test or serum
agglutination test).
• In SAT, test serum is diluted in a series of tubes, then constant defined
amount of antigen is added to each tube and incubates them for ~20h
at 37°C.
• Particular antigen clumps at the bottom of the test tube
• Test is read at 50% agglutination
• Example: Brucellosis screening , Widal Testing (test of Salmonella
3/22/2021 23
25. PASSIVE OR INDIRECT
AGGLUTINATION
• It is easy to read visually and give quick results.
• In this technique, antigen coated particles are prepared for agglutination
reaction.
• Particles, such as erythrocytes, latex, gelatin, and silicates are used.
• For example mixing a soluble antigen with red blood cells that have been
treated with tannic acid or chromium chloride (promote adsorption of
antigen on cell surface).
• The use of synthetic beads or particles provides the advantage of
consistency, uniformity, and stability.
• Problems encountered with the use of erythrocytes as carrier particles are
possibility of cross reactivity with heterophile antibody if the cells used are
nonhuman.
• It is used to detect Antinuclear antibody (of lupus erythematosus),
3/22/2021 25
27. COOMBS TEST
• Coombs test is also known as antiglobulin test (AGT).
• Coombs test is performed using an antiserum containing antibodies that
bridge antibody- or complement-coated RBCs.
• Coombs test used in the preparation of blood for transfusion in cross-
matching, detection of antibodies in the blood plasma of pregnant women
as part of antenatal care, and detection of antibodies for the diagnosis of
immune-mediated haemolytic anemias.
Mechanism:
• Coombs test is based on anti-human antibodies binding to human
antibodies (IgG or IgM). These anti-human antibodies are produced by
plasma cells of non-human animals after immunizing them with human
plasma. These anti-human antibodies will also bind to human antibodies
that may be fixed onto antigens on the surface of red blood cells (RBCs). In
the appropriate test tube conditions, this can lead to agglutination of RBCs
3/22/2021 27
28. TYPES OF COOMBS TEST
2. Indirect Coombs Test:
•Also known as indirect antiglobulin
test (IAT), used to detect in-vitro
antibody-antigen reactions.
•It is used in
1. Blood transfusion preparation
2. Antenatal antibody screening
1. Direct Coombs test:
• Also known as direct antiglobulin
test (DAT), used to detect if
antibodies or complement system
factors have bound to RBCs surface
antigens in vivo.
•It is used to detect
1. Hemolytic disease of the newborn
(or erythroblastosis fetalis)
2. Autoimmune
hemolysis/Immunohemolytic
hemolysis
3. Drug-induced immune-mediated
hemolysis. E.g.: Penicillin (high
3/22/2021 28
30. FLOCCULATION TEST
• Flocculation tests are designed for antibody detection and are based on
the interaction of soluble antigens with antibodies, producing a
precipitate of fine particles that can be seen with the naked eye.
• Example: VDRL slide flocculation test, RPR card test, Kahn’s test for
Syphilis.
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31. REFERENCES
1. Kuby, J., Goldsby, R. A, Kindt T. J., Osborne B. A. (2013). Immunology 7th
edition, W.H. Freeman and Company, New York.
2. Lyolyard, P. M., Whelan, A., Fanger. M. (2011) Instant Notes in Immunology.
3rd edition. Garland Science Taylor and Francis Group, Newyork
3. A. K. Abbas, A. H. H.Lichtman, S. Pillai. (2017).Molecular and Cellular
Immunity. 9th edition. Elsevier
4. C. A. Janeway, P. Travers, M. Walport, M. J. Shlomchick. (2005). Immunology –
the immune system in health and Diseases. 6th edition. Garland Science
Taylor and Francis Group, Newyork
5. K. Murphy, P. Travers, M. Walport. (2008). Janeway’s Immunology. 7th edition.
Garland Science Taylor and Francis Group, Newyork
6. J. M.Cruse, R. E. Lewis. (2009). Illustrated Dictionary of Immunology. 3rd
edition. CRC Press Taylor and Francis Group, New York.
7. Google
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