We know that antigens that are proteins act as potent antigens and can induce the immune system. Similarly if you think about antibodies, they are glycoproteins so logically they also should be able to induce our immune system. There are specific regions on antibodies which can induce the immune system. These regions on antibodies are called antigenic determinants.
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We know that antigens that are proteins act as potent antigens and can induce the immune system. Similarly if you think about antibodies, they are glycoproteins so logically they also should be able to induce our immune system.
There are specific regions on antibodies which can induce the immune system. These regions on antibodies are called antigenic determinants. These antigenic determinants fall under three categories: 1. Isotype, 2. Allotype and 3. That means we have specific set of genes which codes for these heavy chains.
For example, all immunologically normal individuals will have all five types of antibodies present in their serum i. Therefore, different species inherits different constant regions genes and thus expresses different isotypes. So if take antibodies from one species and inject it in another species it would result in anti-isotypic antibody production.
Location: Constant region of heavy chain and light chain. Observed: In all the individuals of a species immunologically normal individuals.
Although all the members of a species inherit the same set of Ig genes, there would be multiple alleles present for these genes which code for different amino acids. That means the amino acid sequence for the same antibody heavy chain would be slightly different in you than in me. So if we take antibodies from one member of the species and inject it into another member of the same species it will result in production of antibodies against allotypic determinants.
Location: Constant region of heavy chain and light chain Observed: During blood transfusion Importance: Monitoring bone marrow grafts Paternity testing Forensic 3.
When we encounter any Ag, the variable region of our Ab recognizes the Ag and our B cells produce specific antibodies during affinity maturation by somatic hypermutaion against that particular Ag. So when we encounter an Ag, our B cell makes very specific or peculiar Abs against it.
Ag a and Ag b and produce IgG1 against both. Location: Variable region of heavy chain and light chain. Observed: When we inject antibodies from a donor who is genetically identical to a recipient, it induces production of anti-idiotypic antibodies. In genetically identical twins the isotype and allotype will be the same but the idiotype will be different.
Isotype, Allotype & Idiotype – What is the Difference?
Help Wikipedia improve by adding precise citations! January Learn how and when to remove this template message The idiotype is based upon the variable region labeled VL and VH in the diagram. In immunology , an idiotype is a shared characteristic between a group of immunoglobulin or T-cell receptor TCR molecules based upon the antigen binding specificity and therefore structure of their variable region. The variable region of antigen receptors of T cells TCRs and B cells immunoglobulins contain complementarity-determining regions CDRs with unique amino acid sequences. They define the surface and properties of the variable region, determining the antigen specificity and therefore the idiotope of the molecule. Immunoglobulins or TCRs with a shared idiotope are the same idiotype. The term "idiotype" is sometimes used to describe the collection of multiple idiotopes, and therefore overall antigen binding capacity, possessed by an antibody.
Antibody isotypes, idiotypes, and allotypes
Allotype Antibodies: Definition & Immunology