(A) Propidium Iodide (PI) uptake by HPMECs transfected with the indicated plasmid after exposure to 0.3 μM of toxin (10 μg/ml) for 3 hours. (B) Immunoblot for DARC and (C) qPCR for DARC transcript in HPMEC after exposure to human whole blood +/− cyclohexamide. (D) PI uptake by HPMEC cells after treatment with human whole blood and exposure to 0.6 μM of toxin (20 μg/ml). (E) Images of and (F) PI uptake by HPMEC cells after transfection with siRNA, treatment with human whole blood, and exposure to 0.6 μM of toxin. Data are pooled from (A, C, D, F) or representative of (B, E) at least three independent experiments. Where relevant, means ± SEM are shown. * p<0.05, ** p<0.01, *** p<0.001 (A, D, F, ANOVA with Tukey’s correction; C, two-tailed student’s t-test).