Figure 6

Flow Cytometry using dihydroethidine staining in P. berghei and P. yoelii to assess viability. (A and B) Histogram distribution of fluorescence in non labelled parasites (control), parasites labeled at the beginning (dashed line) and 3 hours later (solid line) in the same buffer. Dihydroethidine is a vital stain taken up by viable parasites, and which then stains nucleic acid. It is the chemically reduced form of DNA intercalating dye ethidium bromide (B-ring reduction). (C and D) Bar graph analyses of viability in P. berghei and P. yoelii. The data (mean of three independent experiments) show no statistical difference in DHT fluorescence from the beginning and the end of the experiment (99.8 ± 0.09, n = 3 and 99.8 ± 0.1, n = 3; P = 0.823, respectively) and (99.5 ± 0.2, n = 3 and 99.8 ± 0.04, n = 3; P = 0.145, respectively).