Immune responses during human schistosomiasis mansoni. Evidence for antiidiotypic T lymphocyte responsiveness

Abstract

We present a method for the examination of antiidiotypic cell-mediated reactivity during chronic human infections. Pooled and individual sera from patients with schistosomiasis mansoni were purified on immunoaffinity columns of schistosomal egg antigens (SEA). The eluates contained anti-SEA antibodies, but not SEA. These antibody preparations, and their F(ab')2 fragments, stimulated dose-dependent proliferation of peripheral blood mononuclear cells (PBMN) and T lymphocytes from some, but not all active or former schistosomiasis mansoni patients, and could do so autologously. Stimulation required presentation by plastic-adherent cells. The eluates did not stimulate PBMN from persons who had never had schistosomiasis. Affinity-purified anti-SEA antibodies from former patients (cured for > 10 yr) did not stimulate PBMN from patients with active infections. Reabsorption on SEA columns removed stimulatory activity from the eluates. We propose that multiclonal, SEA-related idiotypes expressed by some anti-SEA antibodies stimulate proliferation of T lymphocytes that express antiidiotypic specificities.