Enzyme immunoassay of antibodies to Sjögren's syndrome B antigen.
I describe a solid-phase enzyme immunoassay of IgG-IgA-, and IgM-type antibodies to Sjögren's syndrome B antigen. Polystyrene tubes are coated with the purified antigen. The antibodies are allowed to bind with their antigens, and then detected with alkaline-phosphatase-conjugated anti-human IgG, IgA, or IgM sera. The amount of alkaline phosphatase fixed to the tubes is determined in pH 10.0 diethanolamine buffer at 37 degrees C with p-nitrophenyl phosphate as substrate. The absorbance of the p-nitrophenolate ion liberated in 1 h at 37 degrees C is measured at 406 nm. When rheumatoid factor is present, the values obtained for IgG antibodies are too low, and those for IgM antibodies are too high.
D000906:Antibodies / Q000032:analysis*; D000936:Antigen-Antibody Complex; D000956:Antigens, Viral / Q000032:analysis*; D001324:Autoantigens; D006801:Humans; D007124:Immunoenzyme Techniques; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D012859:Sjogren's Syndrome / Q000276:immunology*
D000906:Antibodies; D000936:Antigen-Antibody Complex; D000956:Antigens, Viral; D001324:Autoantigens; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; C030352:rheumatoid arthritis nuclear antigen