Hapten-Specific IgE Antibody Responses in Mice

Abstract

These studies were conducted to investigate the effects of various adjuvants on antibody responses of the IgE and IgG classes in mouse strains of the high IgE response phenotype. Administration of either complete or incomplete Freund's adjuvant or aluminum hydroxide gel (alum) at appropriate times was found to generate a nonspecific suppression of antibody responses of both the IgE and IgG classes. Such “adjuvant-generated suppression” could be induced both in intact animals and could be passively transferred with cells from adjuvant-pretreated donors. It was shown that T cells were essential for the suppression, since pretreatment of spleen cells from adjuvant-inoculated mice with anti-ϑ serum plus complement abolished the suppressive effects of such transferred cells. Moreover, the generation of these suppressor T cells could be inhibited by pre-exposing donor animals to low doses of x-irradiation at an appropriate time before adjuvant administration. On the other hand, once suppressor cells have been induced by inoculation with complete Freund's adjuvant, x-irradiation had little effect in diminishing the suppressive activity of such cells. The relevance of adjuvant administration to induce suppressor mechanisms for both IgE and IgG antibody responses to regulatory control mechanisms of the immune response is discussed.