Production and characterization of monoclonal antibodies against Trypanosoma cruzi-associated antigens.

Nine monoclonal antibodies (mAb) recognizing characteristic antigens in Trypanosoma (T.) cruzi were obtained from hybridomas which had been established by a fusion between mouse myeloma cells and the spleen cells of a mouse immune to the epimastigote form of T. cruzi (Tulahuen strain). Antigen specificities of these mAb were assessed by an indirect immunofluorescence (IIF) method using T. cruzi in different life cycles (amastigote and trypomastigote) and other members of the Trypanosomatidae. The mAb were classified into 3 groups from their reaction patterns to different parasites: 1) The strain specific mAb that reacted only with T. cruzi Tulahuen epimastigote, 2) the species specific mAb that reacted with all T. cruzi strains but not with other species of parasites, and 3) the mAb that were cross-reactive with other species of Trypanosomatidae. Most mAb were specific to epimastigote form of T. cruzi, but some reacted weakly with trypomastigote and amastigote form of the parasites. Immunoblotting and glycolipid analyses of the membrane fraction of homogenized parasites using the mAb identified at least 3 distinct antigenic molecules; those of protein nature having Mr. 43,000 and 58,000 and Mr. 43,000 and 62,000 and molecule(s) of glycolipid nature.