In vitro infection with Trypanosoma cruzi in peritoneal macrophages (PM) of mice with different susceptibility to systemic homologous challenge

M. TAMAE, A. PÉREZ, M.J. SVETAZ, E. ROGGERO, O. BOTTASSO AND S. REVELLI.

Rosario, Argentina

Otro; XIX Annual Meeting of Biology Society of Rosario; 1999

Sociedad de Biología de Rosario.

Biocell 24(2), 2000 XIX  Annual Meeting of Biology Society of Rosario     In vitro infection with Trypanosoma cruzi in peritoneal macrophages (PM) of mice with different susceptibility to systemic homologous challenge   M. Tamae, A. Pérez, M.J. Svetaz, E. Roggero, O. Bottasso and S. Revelli. Instituto de Inmunología, Fac. Cs. Médicas, Dept. Bioquímica Clínica, Fac. Cs. Bioquímicas y Farmacéuticas, UNR.   Inoculation with T. cruzi in C57Bl/6 and Balb/c mice was shown to results in an easily noticeable acute disease, more intense in the C57Bl/6 strain that shoed higher tumor necrosis factor (TNF-a) serum concentrations, whereas Balb/c mice overcome this process regaining normal weight. Considering that T. cruzi mostly infects macrophages, we wished to analize whether the different morbimortality of both experimental infections were related with changes in the antiparasitic activity of macrophages. PM from 60-day old mice were cultured in 12-well microplaques containing RPMI supplemented BFS, 105 cell/well. Upon overnight incubation, culture medium was replaced and cells exposed at different intervals following exposure yielding no significant differences between both groups. Cells supernatants were collected 48 h later for assessment of nitrite accumulation (as an indicator of nitric oxide production) and TNF-a  levels values being  recorded in C57Bl/6 mice (i.e., 1:1 ratio, mean±sem) C57Bl/6 148±29, n=4, Balb/c 8.2±8, n=4 (p=0.014, U test). In keeping with serum results, aggravated acute disease of C57Bl/6 mice was associated with a greater macrophage TNF-a production, upon exposure to T. cruzi.