Toxin-antitoxin reaction

Toxin-antitoxin reaction

A term used in serology to denote the combination of a toxic antigen with its corresponding antitoxin. If the antitoxin is derived from any species other than the horse, precipitation occurs over a wide range of reactant ratios, 20 × or more, as in other antigen-antibody reactions. With horse antitoxin, flocculation occurs only if toxin and antitoxin are near equivalence, a twofold excess of either reactant giving soluble complexes. In most instances, the reaction results in partial or complete neutralization of the toxic activity of the antigen. See Antibody, Antigen, Antitoxin, Neutralization reaction (immunology), Serology

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