The development of a radioallergosorbent test (RAST) for murine IgE antibodies

Abstract

A purified monoclonal IgE preparation, isolated from the ascitic fluid of mice bearing a hybridoma secreting IgE with specificity to ovalbumin, was used for the production of goat anti-murine IgE (GAME) antiserum, which was then rendered monospecific for the epsilon chain. Another monoclonal hybridoma IgE preparation with specificity for the 2,4-dinitrophenyl group was isolated from ascitic fluid in a relatively pure state by affinity chromatography and used in the form of an immunosorbent to isolate antibodies from the monospecific goat serum. The GAME antibodies were 125I-labeled and used to develop a radioallergosorbent test (RAST) for the quantitation of murine IgE antibodies specifically adsorbed onto antigen-coupled paper discs. The RAST was specific for antibodies of the IgE class only and was as sensitive as and more accurate than PCA assay. RAST results on sera of mice treated with tolerogenic conjugates indicated a reduction in the affinity and concentration of the IgE antibody populations on suppression of the IgE response. The effect of interference by non-IgE antibody populations on the RAST curves has been discussed.