Interaction of Trypanosoma cruzi with macrophages influence of temperature.

The interaction of macrophages and T. cruzi has been studied in vitro culture under three different temperatures. After 24 hours incubation at 29 degree C a large number of recognizable parasites inside macrophages is observed with evidences of cell divisions. At video microscopy they show a slow motion and a predominance of epimastigotes and some round shapes (amastigotes). This was corroborated at the light and electron microscopes. No evidence of lysis in the phagosome vacuoles was observed. At 40 degrees C, macrophages show a large number of residual bodies and phagocytic vacuoles with digested parasites. At 37 degrees C, an intermediate stage with normal and digested parasites inside macrophages is observed. No significant evidences of affected phagocytic and degradative properties of the macrophages were obtained at those temperatures. It is postulated that temperature mainly affects the parasite resistance to intracellular digestion.