Antigen- and IgE class-specific suppression mediated by T suppressor cells of mice treated with...

Various size polymers are obtained following glutaraldehyde treatment of native ovalbumin (OA). OA-POL, approximately 35 X 10(6) daltons, was prepared at the isoelectric point of OA. Treatment of CBA mice with microgram amounts of OA-POL led to efficient antigen-specific suppression of IgE responses. IgG anti-OA antibodies were not suppressed. Transfer of cells from OA-POL-treated donors into normal, unprimed recipients interfered with the ability of these animals to mount a primary or secondary IgE response. In addition, cotransfer of spleen cells from OA-POL-treated mice along with OA (in alum)-primed cells, into irradiated syngeneic recipients resulted in IgE class-specific suppression that was abrogated by treatment of OA-POL donor cells with monoclonal anti-Thy 1.2 + complement. The presence or absence of T cells in the OA-POL population had no effect on IgG levels in the recipients. Analysis of the antigenic properties of OA-POL revealed 5-15% cross-reactivity with native OA as perceived by IgG or IgE antibodies. In contrast, OA-POL was highly cross-reactive at the T cell level as shown functionally by its potent induction of OA-specific, IgE-selective suppressor T cells. The results suggest that the beneficial effects of glutaraldehyde-modified allergens, recently introduced in the immunotherapy of atopic individuals may be due to the preferential exposure on the polymerized protein, of antigenic determinants generating T suppressor cells and to the selective loss of B cell-reactive determinants.