Figure 4.

Autophagy participates in the control of T. cruzi infection by macrophages. RAW macrophages were infected for 24 h, washed and fixed or incubated for 24 or 48 h more before fixation. Fixed samples were then processed for microscopy (see details in materials and methods). Other samples were treated with 10 mM DFMO or 20 μM CQ for 2 h before infection (pre-treatment) and maintained in the same conditions during infection and chase periods followed by fixation and processing. (a): Scheme of the protocol. (b): Percentage of macrophages infected at progressive times in control conditions. Bars indicate the mean ± the standard error of at least four independent experiments. Number of counted cells: 100 (Tukey test, *p < 0.05; **p < 0.01). (c): Representative images depicting the level of cellular infection at 24 h under the indicated conditions. Parasites were visualized in green, actin cytoskeleton in red and the nuclei in blue. Bars: 5 μm. (d): Percentage of infected cells in the absence (control) or the presence of the autophagic inhibitors DFMO or CQ at each indicated time. Bars indicate the mean ± the standard error of at least three independent experiments. Number of counted cells: 100 to 300 cells each experiment (Tukey test, * p < 0.05; **p < 0.01; ***p < 0.001).