Specific antibodies, production procedures

In a recent procedure to detect carcinogen-DNA adducts by radioimmunoassay, A-(guanosin-8-yl)acetylaminofluorine was linked to BSA by the periodate method, and the conjugate was used to elicit specific antibodies to this product, which is formed when N-acetoxy-2-acetylamino-fluorene reacts with DNA. 

Individual animals immunized with the same substance can produce antibodies that may differ in affinities, titer, and specificities. " Such differences are appeu-ent with antibodies studied by the more classical physical chemical procedures. However, even among anti-enzyme sera harvested from individual rabbits that had been immunized with -lactamase, some were found to neutralize the activity of the enzyme, others to stimulate its activity, and still others were stimulatory and then inhibitory at higher concentrations." In radioimmunoassay, each antiserum from an individual animal must be characterized separately to select those that have the proper affinities and specificities. The production of monoclonal antibodies by hybridoma technology can yield molecules with defined specificities and affinities. As this technology becomes affordable for the average research laboratory, problems associated with antibody heterogeneity are due to diminish. 

Immunoglobulin preparations are concentrated protein solutions derived from the pooled plasma of adults or animals. They contain specific antibodies in proportion to the infectious and immunization experience of the population from whose plasma they are prepared (1). Large numbers of donors (at least 1000 donors per lot of final product) are used, in order to ensure inclusion of a broad spectrum of antibodies. Intravenous immunoglobulin is also derived from the pooled plasma of adults, but the alcohol-fractionation procedure is modified to a product suitable for intravenous use. The use of intravenous immunoglobulins in selected immunodeficiency and autoimmune diseases has been reviewed (2). 

The procedures for production of specific antibodies and their application in a competitive inhibition ELISA (Enzyme-Linked Immunosorbent Assay) are discussed in detail in the preceding chapter (Vanderlaan et al., this volume). In addition, other comprehensive overviews of the immunoassay development process in the pesticide field are available in general, a... 

ELISA assays exist in a number of formats. In some cases the reaction product absorbs light, and in other cases the product is strongly fluorescent. The second antdxidy is not always labeled with enzyme but rather is sometimes detected with yet another antibody that contains the bound enzyme. This procedure eliinioates the need to attach probe or enzyme to a specific antibody which may be in short supply. 

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