ELISA quantitation of IgG subclass antibodies to dietary antigens

Abstract

The IgG subclasses of human antibodies against 2 dietary antigens, ovalbumin (OA) and beta-lactoglobulin (BLG), were studied by ELISA using monoclonal anti-human IgG subclass antibodies. Under the assay conditions used, the anti-IgG subclass antibodies were subclass specific. Quantitative estimates of the subclass antibodies were obtained by reference to a ‘capture’ assay using F(ab′) 2 anti-light chain antibody as ligand and IgG myelomas as standards. The validity of these estimates was supported by antibody quantitation using the Farr assay. In healthy adults with serum anti-OA or anti-BLG antibodies, anti-OA antibodies were found mainly in the IgG1 ( 9 11 ) and IgG4 ( 6 11 ) subclasses, whereas 5 sera showed high levels of IgG2 antibodies. In contrast, the IgG subclass distribution of anti-BLG antibodies was predominantly IgG4 ( 10 10 ).