Calcium Ionophore, Calcimycin, Kills Leishmania Promastigotes by Activating Parasite Nitric Oxide Synthase

Figure 2

Two-parameter, two-colour analysis of cell death in L. major promastigotes treated with calcimycin. (a) PI stains dead cells with penetrable plasma membrane and its fluorescence was detected in both red (FL3) and orange (FL2) ranges of the spectrum. Laser dye styryl- (LDS-) 751 stains live cells with polarized mitochondria and was measured in red (FL3) fluorescence channel. Double-negative cells correspond to cells with depolarized mitochondria but an integral plasma membrane. The graphs are representative of six independent experiments. (b) The ratio of live promastigotes with intact plasma membrane and polarized mitochondria (PI^-LDS-751⁺), cells with intact plasma membrane and depolarized mitochondria (PI^-LDS-751^-), and dead cells with penetrable plasma membrane and depolarized mitochondria (PI⁺LDS-751^-) in samples treated with different concentrations of calcimycin. Data are presented as mean ± SD (six independent experiments; each assay was performed in triplicate). Percentages of particular populations were compared using Mann–Whitney test. corresponds to , corresponds to , and corresponds to .

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