Figure 6: Oxidative burst of L. mexicana-infected macrophages. Cells were treated with PPAR agonists 24 h before infection, and the oxidative burst was determined by NBT reduction. NBT was added simultaneously with promastigotes. (a) After the indicated times after infection, slides with infected macrophages were washed and stained for 30 min with Fuccina. Microphotographs show positive cells to NBT reduction in comparison with control cells, which were treated or not with agonists in the presence of NBT. (b) The graph shows percentage of cells positive to NBT reduction. (c) Quantitative analysis of NBT reduction of macrophages infected and treated or not with PPAR agonists. Graph bars are mean ± SEM of three independent experiments, and statistical analysis was done comparing, for each time, treated versus nontreated macrophages; (*) , (**) , and (***) .