title: Ammonium sulfate coprecipitation antibody determination with purified staphylococcal enterotoxins.
abstract: The ammonium sulfate coprecipitation technique of Farr was applied in a study of the purified enterotoxins of Staphylococcus aureus. Ammonium sulfate coprecipitation of iodine-131-labeled enterotoxins A, B, and C, with the use of a 1.6 m concentration of (NH(4))(2)SO(4), revealed differences in the antigen-binding capacity of normal and immune rabbit sera for the enterotoxins. The coprecipitation technique provided a quantitative test for detecting antibody to enterotoxin that was more sensitive than agar-gel diffusion methods. Antigen-binding tests suggested the presence of similar antigenic determinant groups in all three toxins. Measurable antigenbinding capacities for enterotoxins A, B, and C were detected in sera of normal human subjects and became elevated in several subjects accidently exposed to enterotoxin.
mesh_terms: D000818:Animals; D000906:Antibodies; D000937:Antigen-Antibody Reactions; D011232:Chemical Precipitation; D004768:Enterotoxins; D006801:Humans; D007106:Immune Sera; D005779:Immunodiffusion; D007456:Iodine Isotopes; D008722:Methods; D011233:Precipitin Tests; D000644:Quaternary Ammonium Compounds; D011817:Rabbits; D013210:Staphylococcus
chemical_list: D000906:Antibodies; D004768:Enterotoxins; D007106:Immune Sera; D007456:Iodine Isotopes; D000644:Quaternary Ammonium Compounds