Zymodeme and species specificities of monoclonal antibodies raised against Trypanosoma cruzi.

A series of hybrid cell lines was generated by the fusion of Sp2/0 myeloma cells with spleen cells from BALB/c mice that had been immunized or infected with Trypanosoma cruzi zymodemes (Z1, Z2, Z3 ). Four immunoglobulin isotypes, IgM, IgG1, IgG2a and IgG3 were represented amongst the monoclonal antibodies secreted by 22 hybridoma clones. On indirect immunofluorescence (IFAT) antibodies bound to flagellum, cytoplasm, cell membrane or stained the whole organism. Two antibodies were epimastigote-specific. Enzyme-linked immunosorbent assays (ELISA) and a dot immunobinding test were used to evaluate the zymodeme and species specificities of 13 antibodies: four reacted with all T. cruzi zymodemes tested, two reacted strongly with all except Z1, two predominantly with Z1, two predominantly with Z2, and three predominantly with Z3 . Two IgM antibodies cross reacted with Trypanosoma rangeli, T. brucei, Leishmania mexicana, L. braziliensis and L. donovani. Five antibodies were used in a preliminary immunobinding test, performed blindly, to compare monoclonal reactivities and zymodeme groups. The results suggested a correlation between the two methods of characterization. Anti-T. cruzi monoclonal antibodies are considered to have important applications to epidemiological studies and the improved diagnosis and prognosis of Chagas' disease.