An immunoaffinity-purified Trypanosoma cruzi antigen suppresses cellular proliferation through a TGF-beta-mediated mechanism.

Abstract

Two subfractions with opposite immunological properties were obtained from the flagellar antigens (FF) of Trypanosoma cruzi epimastigotes by immunoaffinity chromatography. The ligand-bound material (Ag 123) contained four polypeptide bands of 97, 55, 38 and 14 kDa. The nonretained flow-through (FT), induced a potent proliferation of murine naive splenocytes. In contrast, Ag 123 inhibited the proliferative capacity of the FT as well as the proliferation mediated by the mitogen Concanavalin A (Con A). The suppressive effect of Ag 123 on the Con A-mediated proliferation was neutralized by an anti-TGF-beta monoclonal antibody. Both Ag 123 and FF stimulated high serum levels of TGF-beta in inject..