Figure 2

Effects of probenecid on transport kinetics in 384-well format. (A) Uninfected cells have a large fluorescence signal in 1 mM Ca⁺⁺ (circles), which is abolished by addition of 5 mM probenecid (triangles). (B, C, D) Fluorescence kinetics for erythrocytes infected with indicated parasite lines in the absence or presence of probenecid (circles and triangles, respectively). Note that parasite genotype influences the magnitude of probenecid-associated increase in fluorescence. (E) Mean ± S.E.M. effects of probenecid addition at 12 h, normalized to 0% for no effect. n = 5-7 trials each; P < 10^-5 and < 0.02 for comparisons of Dd2 to uninfected and HB3, respectively. (F) Kinetics of Fluo-8 efflux from uninfected cells in the absence or presence of 5 mM probenecid (circles and triangles, respectively). Error bars, S.E.M. of replicates; representative of two experiments.