title: Blocking of nonspecific IgG in indirect radioimmunoassay for detecting Ascaris suum antigens.
abstract: The sensitivity of an indirect radioimmunoassay (IRIA) used for detecting larval body wall (LBW) antigens of Ascaris suum was enhanced by using various blocking agents which prevented nonspecific binding of immunoglobulin G (IgG) or free 125I without preventing binding of specific antibodies to the antigen. The use of blocking agents reduced counts for both positive and negative sera, resulting in an increase in calculated binding ratios (BR) and deltas and, thus, in the sensitivity of the assay. The relative effectiveness of blocking agents, in decreasing order, were turkey serum (TS), rabbit gamma globulin (RGG), rabbit whole serum (RS), bovine serum albumin (BSA), rabbit IgG (RIgG), bovine alpha globulin (BAG), bovine gamma globulin (BGG) and Tween-20.
mesh_terms: D000510:Alpha-Globulins / Q000494:pharmacology; D000818:Animals; D000906:Antibodies / Q000276:immunology*; D000947:Antigens, Helminth / Q000032:analysis*; D001200:Ascaris / Q000276:immunology*; D001667:Binding, Competitive; D007074:Immunoglobulin G / Q000276:immunology*; D011136:Polysorbates / Q000494:pharmacology; D011863:Radioimmunoassay; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D005719:gamma-Globulins / Q000494:pharmacology
chemical_list: D000510:Alpha-Globulins; D000906:Antibodies; D000947:Antigens, Helminth; D007074:Immunoglobulin G; D011136:Polysorbates; D005719:gamma-Globulins; D012710:Serum Albumin, Bovine