Figure 6

Labelling of Trypanossoma cruzi epimastigotes with monodansylcadaverine (MDC) after treatment in the absence or presence of solenopsins. After cultivation for 48 h in BHI–FCS medium (A, BHI), PBS (B, PBS), or BHI–FCS medium supplemented with 0.3 µM of solenopsins from Solenopsis invicta (C, INV) or S. saevissima (D, SAE), CL-Brener epimastigotes were collected and incubated with 50 μM of MDC for 1 h at 28 °C, washed 3 × in PBS, fixed, and examined in an epifluorescence microscope as described in Methods. Bars = 20 µm. To quantify the MDC labelling, 5 × 10⁷ parasites treated as described were lysed in Tris-HCl (pH 8.0) with 1% SDS, centrifuged, and fluorescence from the supernatants measured with a microplate reader. Plot (E) presents the mean ± SD fluorescence values (in % relative to BHI) of three independent experiments. Statistics: treatments were compared with Kruskal–Wallis at alpha = 0.05; INV (light-grey bar) and SAE (dark-grey bar) indicates statistically similar treatment results; an asterisk indicates values statistically different from the control (BHI). For details on analyses (e.g. p values), see the supplementary R script file.