Figure 3.

Inhibition of ABCC-like activity by MK-571 in trypomastigote forms of the T. cruzi Y strain. ABCC-like activity was evaluated by the carboxyfluorescein (CF) efflux assay. 10⁶ trypomastigotes were incubated in medium containing 2.5 μM CFDA in the presence or absence of 7.5 mM probenecid, 600 μM indomethacin or 200 μM MK-571 for 30 min. Parasites were then centrifuged and incubated in medium in the presence or absence of the modulators for another 30 min. After incubation, parasites were centrifuged, suspended in PBS and kept on ice for acquisition by flow cytometry. Graph in (A) represents the median fluorescence intensity (MFI) for CF, in (B) the percentages of CF+ parasites for the assay performed at 37°C. Inhibition index of CF efflux (Δ) was calculated by the ratio between the CF MFI of the parasite in the presence of the modulator and the CF MFI in the absence of the modulator (CTL). Comparison between Δ indexes are shown in the graphs in (C) for modulators and in (D) trypomastigote and epimastigote forms. The Friedman (A–C) and Man–Whitney (D) statistical test were used with n = 11 independent experiments. Lines represent the median for each group and the significance values were represented by ^*p < 0.05, ^**p < 0.01, and ^***p < 0.001.