FIG 3.

P. falciparum-iRBCs and their lysates strongly increase the permeability of HBMEC monolayers. The changes in HBMEC monolayer integrity in response to different dosages of (A) intact iRBCs in the schizont stage or (B to D) their lysates (iRBCLs) were measured using (A to C) xCELLigence RTCA Biosensor technology or (D) the leakage of FITC-dextran in a filter assay. The concentrations are expressed as the number of RBCs or iRBCs (×10⁶) per surface area (square centimeters) of the cell culture well. (A) Uninfected RBCs (8 × 10⁶/cm²) or (B to D) their lysates (RBCLs) (8 × 10⁶/cm²) from the same blood donation were included as a control. (C) HBMEC monolayers were preincubated with 200 μM losartan for 1 h prior to addition of the lysates (8 × 10⁶/cm²). (D) The leakage of FITC-dextran is expressed as fold change relative to the medium control. Results represent the average from 3 independent experiments with standard deviations. Statistical significance was determined by (A, C, and D) one-way ANOVA with Tukey’s multiple-comparison test or (B) the Kruskal-Wallis test with Dunn’s multiple-comparison test (*, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001).