title: A microassay for antibody binding to tumor cell surface antigens using 125I-labelled protein a from Staphylococcus aureus.
abstract: A sensitive assay for antibodies bound to the surface antigens of adherent tumor cells using protein A from Staphylococcus aureus is described. Cells, as monolayers in microtest wells, are incubated first with immune or control serum, and then with 125I-labelled protein A (IPA), which binds to IgG antibodies bound to cell surface antigens. The IPA assay is shown to be more sensitive than the conventional isotopic antiglobulin (IAG) assay, because IPA binds to a lesser extent to IgG bound non-specifically to cells.
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000032:analysis; D000951:Antigens, Neoplasm / Q000032:analysis*; D001426:Bacterial Proteins / Q000378:metabolism*; D001666:Binding Sites, Antibody; D004306:Dose-Response Relationship, Immunologic; D005354:Fibrosarcoma / Q000276:immunology; D007118:Immunoassay; D007457:Iodine Radioisotopes; D007519:Isoantigens / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D013211:Staphylococcus aureus / Q000276:immunology*
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000951:Antigens, Neoplasm; D001426:Bacterial Proteins; D007457:Iodine Radioisotopes; D007519:Isoantigens