Trypanosoma cruzi: Immunological properties of a soluble extract of culture forms

Immunological properties of a soluble Trypanosoma cruzi antigen were studied by Ouchterlony double-diffusion, immunoelectrophoresis, and fractionation procedures. Immune human serum was used with the antigen, and five precipitin bands could be demonstrated by double diffusion and immunoelectrophoresis. Five peaks with different physicochemical properties were demonstrated by gel fractionation, but only peaks II, III, and IV were antigenically reactive by the complement-fixation reaction, and peaks III and IV, by the hemagglutination test.