KLH) ~ with AI(OH)3 as adjuvant and then infected with third stage larvae of Nippostrongylus brasiliensis and finally injected with dinitrophenylated pro- tein ofN. brasiliensis (DNP-Nb) as the challenging agent, high titer antihapten IgE

It has been shown that preferential production of IgE antibody may be obtained in certain strains of mice if the adjuvant is Al(OH)3 (1). A high and persistent titer of IgE antibody can thus be obtained using minute doses of antigen and even booster responses can be produced (2). If mice are primed with microgram amounts of dinitrophenylated keyhole limpet hemocyanin (DNPKLH) ~ with AI(OH)3 as adjuvant and then infected with third stage larvae of Nippostrongylus brasiliensis and finally injected with dinitrophenylated protein ofN. brasiliensis (DNP-Nb) as the challenging agent, high titer antihapten IgE antibody can be obtained (3, 4). In this model, the infection by N. brasiliensis stimulates helper T cells which collaborate successfully with hapten-specific B cells (3, 4). 7 days after the injection of DNP-Nb, high antihapten IgE titers are observed in all strains used. High titers of antihapten IgE persist in the circulation for several weeks except in the SJL strain (3). It has also been shown that antibody production is controlled not only by helper T cells but also by suppressor T cells (5-8). In the present paper the suppressor cells in the SJL strain of mice were investigated. It was found that T cells and also thymocytes from normal SJL mice have a suppressor effect on IgE production. Using F~ hybrids and backcrosses to SJL mice we could demonstrate that the suppressive function is inherited by a single Mendelian gene, not linked to the H-2-gene complex.