Antigenic site description

An antigen injected into a test animal elicits an immune response by binding to determinant specific receptor sites on two types of small lymphocytes denoted B and T. These receptor sites have been shown to be immunoglobulins integrated into the lymphocyte cell membrane, which accounts for their determinant specificity. A few characteristics of B and T lymphocytes are listed in Table 8-2, but their ontogeny, function, and interactions are immensely more complex than such a casual description... 

A brief description of techniques used in EIA follows. The various assays have been classified as either competitive or noncompetitive assays, depending on whether or not the technique involves a reaction step in which unlabeled and labeled antigen compete for a limited number of antibody sites (competitive assay) or whether the antigen (or antibody) to be measured is first allowed to react with antibody (antigen) on a solid phase followed by measurement of the binding of enzyme-labeled immune reactant (noncompetitive assay)... 

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