Suppression of Hapten-specific Antibody Response by Carrier-specific T Cells

Abstract

THYMUS-derived lymphocytes (T cells) are known to assist in the induction of antibody formation by bone marrow-derived lymphocytes (B cells) against a variety of antigens. In some antibody responses, however, T cells apparently suppress antibody synthesis by B cells^1–4 although the mechanisms involved in this inhibitory cell interaction have not been well analysed. Most previous reports on suppressor T cells have dealt with nonspecific influences, while we have reported an antigen-specific inhibitory effect of T cells on IgE class homocytotropic antibody formation in the rat⁵. T cells obtained from carrier-primed donors exert a strong suppressive effect on the hapten-specific IgE antibody response of recipients immunized with the hapten on the same carrier, whereas cells obtained from donors immunized with an unrelated antigen showed no such inhibitory activity⁵. Thus the inhibitory cell interaction seemed to occur between carrier-specific T cells and hapten-specific B cells. Here we demonstrate a similar inhibitory cell interaction in an anti-hapten IgM antibody response in the mouse using a simple cell transfer technique. The results provide direct evidence that suppressor activity is exerted by thymocytes and θ-bearing spleen cells with definite carrier specificity.