Human serum thyroglobulin determination with monoclonal antibody one-step assay: minimum interference of autoantibody.
Combination of two thyroglobulin monoclonal antibodies (monoAbs) recognizing epitopes which are rarely recognized by an antibody enabled us to develop a rapid one-step enzyme immunoassay of serum Tg. Of 87 monoclonal antibodies, 20 were selected for the purpose. The method is a sandwich technique employing a monoAb covering microplate and horse-radish peroxidase monoAb conjugate. A combination of monoAb 7A7A solid phase and 31A2E for the conjugate gave the best results. The assay takes 60 min and the minimal detectable amount is 2 ng/ml. Intraassay variation is from 4 to 7%. Interassay variation is 5 to 12%. The recovery rate for Tg added to normal sera is between 89 and 111%. The correlation coefficient with the polyclonal antibody method in Tg hemagglutination negative sera is 0.98. The presence of autoantibody in sera up to 10 X 2(4) hemagglutination titer does not affect the recovery rate to a statistically significant extent.
D000911:Antibodies, Monoclonal; D001323:Autoantibodies / Q000032:analysis*; D003429:Cross Reactions; D006111:Graves Disease / Q000097:blood; D006801:Humans; D013954:Thyroglobulin / Q000097:blood*
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D013954:Thyroglobulin