Figure 4

The dose-dependent effect of hydrogen peroxide on the expression of markers of apoptosis in Plasmodium berghei ookinetes. Ookinetes were incubated in a range of concentrations of H₂O₂/RPMI 1640 medium for 1 h. The proportion of parasites containing nuclei with condensed chromatin, detected using acridine orange staining (A), or expressing phosphatidylserine on the outer surface, detected with annexin (B), was recorded as apoptotic. Staining with propidium iodide was used to identify dead ookinetes. Within a particular condition, bars that do not share the same letter are significantly different (p<0.05), n = 40 ookinetes per sample. Error bars = SEM for four experimental repeats.