Trypanosoma cruzi: Peripheral Blood Monocytes and Heart Macrophages in the Resistance to Acute Experimental Infection in Rats

摘要: The contribution of mononuclear phagocytes to host resistance against acute Chagas disease has been studied in vivo a rat model inoculated with Trypanosoma cruzi, Y strain. Acute T. cruzi infection triggered dramatic increase (937%) peripheral blood monocyte number at day 12 infection. At this point, histological analysis the heart showed high parasitism and diffuse moderate intense inflammatory process. Ultrastructural study revealed large macrophages, addition lymphocytes undiffer entiated cells. Clusters macrophages exhibited different morphologi cal phenotypes, evident signs activation (increase size, surface rufflings, amount cytoplasmic organelles). Cell-to-cell contacts involving or mono cytes were observed. Depletion by treatment silica, selective cytotoxic agent for these cells, caused significant amastigote nests cardiomyocytes. present findings indicate that early phase induces rapid production, maturation, monocyte/macrophage system so as control replication, emphasizing crucial role disease.