A three-layer immunoradiometric assay for antibodies in different immunoglobulin classes and its application to the detection of chicken thyroglobulin autoantibodies and of antibodies to sheep erythrocytes.
A versatile solid-phase assay for detection of antibodies in different immunoglobulin classes is described. The assay has been applied to: (1) the detection of IgG and IgM anti-thyroglobulin autoantibodies in chickens with spontaneous autoimmune thyroiditis, and (2) the detection of anti-sheep cell antibodies in normal chickens. Thyroglobulin-coated plastic tubes or formaldehyde-fixed sheep erythrocytes were used as the solid phase. Antisera were added in succession to the solid-phase antigen so as to form 3 antibody layers: (1) chicken antibody against the solid-phase antigen; (2) heavy-chain-specific rabbit anti-chicken immunoglobulin; and (3) 125I-labelled goat anti-rabbit immunoglobulin. The assay is suitable for routine determinations on large numbers of samples; its sensitivity enables small volumes of serum to be tested and allows considerable economy in the use of valuable class-specific antisera. The radiolabelled reagent can be readily applied to other assays employing rabbit antisera.
D000818:Animals; D001323:Autoantibodies / Q000032:analysis*; D002645:Chickens / Q000276:immunology; D004912:Erythrocytes / Q000276:immunology; D007074:Immunoglobulin G / Q000032:analysis*; D007075:Immunoglobulin M / Q000032:analysis*; D007518:Isoantibodies / Q000032:analysis*; D011817:Rabbits; D011863:Radioimmunoassay / Q000379:methods*; D012756:Sheep / Q000097:blood; D013954:Thyroglobulin / Q000276:immunology
D001323:Autoantibodies; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007518:Isoantibodies; D013954:Thyroglobulin