Fig 3. Drug-sensitivity and growth rate of asexual blood stages of three P. falciparum reporter lines (GFP@cam, GFP@gapdh, GFP@hsp70).

A. Sensitivity to the drugs BSD and WR99210 as determined by flow cytometry in standard 72 h cultures in 96 well plates. Cultures of infected red blood cells (RBC) were incubated with different drug concentrations (in triplicate) and after 72 h samples were stained with the DNA-specific dye, Hoechst 33258, to determine parasitemia (% of infected RBC) by flow cytometry. Dot plots are shown of uninfected RBC (control, upper panel) selected using Forward Scatter parameter (FSC-A) and from cultures with the lowest and highest drug concentration (G1: infected RBC). Parasite survival is defined as the percentage of infected RBC in drug-treated wells divided by the percentage of infected RBC in non-treated wells multiplied by 100. IC₅₀ values WR99210 (nM): (NF54 PfWT) 0.16; (GFP@cam) 0.25; (GFP@gapdh) 0.27; (GFP@hsp70) 0.19. IC₅₀ values BSD (μg/ml): (NF54 PfWT) 0.48; (GFP@cam) 0.34; (GFP@gapdh) 0.54; (GFP@hsp70) 0.48. B. The growth rate of asexual blood stages in cultures maintained in the semi-automated culture system for a period of 5 days. Cultures were initiated with a parasitemia of 0.5%.