The induction of apoptosis in HLECs or HBECs co-cultured with <i>P. falciparum</i> PRBCs depends on the culture conditions.

<p>A) Co-cultured endothelial cells (ECs) and parasitized red blood cells (PRBCs) after Annexin V and propidium iodide (PI) staining. B) Human lung endothelial cell (HLEC) apoptosis induced by the different <i>P. falciparum</i> isolates (A, B and C) when the co-cultures are made in the standard culture media (LCm) or in the modified culture medium (MLCm). C) Human brain endothelial cell (HBEC) apoptosis induced by the different <i>P. falciparum</i> isolates (A, B and C) when the co-cultures are made in the standard culture media (BCm) or in the modified culture medium (MBCm). The percentage of apoptotic cells was calculated after microscopy enumeration of Annexin V and propidium iodide positive cells in 1000 ECs. The results are expressed as mean values, and standard deviation are shown for duplicate wells from three biological replicates. Significance at <i>p</i><0.005 is indicated by **.</p

Primers used for reverse-transcriptase polymerase chain reaction (RT-qPCR) experiments.

<p>Primers used for reverse-transcriptase polymerase chain reaction (RT-qPCR) experiments.</p

Direct cell-to-cell contact is needed for optimal induction of EC apoptosis.

<p>HLEC (A) and HBEC (B) co-cultured with individual supernatants harvested from cultured <i>P. falciparum</i> isolates or in transwell plates where the PRBC are incubated on top of the ECs. The results show reduced levels of apoptosis as compared to those observed in co-cultures where PRBC and ECs are in direct contact. For all experiments the means and standard deviation were calculated from duplicate wells from three biological replicates. Significance at <i>p</i><0.05 is indicated by *.</p

Variation of gene expression when <i>P. falciparum</i> isolates were incubated with ECs.

<p>The implication of the seven selected genes in the ability of isolates B and C to induce the lung and brain EC death was represented as a ratio by comparing their RNA levels in co-cultures using the modified culture mediums, where EC apoptosis death was detected. For all experiments the means and standard deviation were calculated from duplicate wells from two biological replicates.</p><p>*p<0.05,</p><p>**p<0.005,</p><p>***p<0.0005.</p><p>NS = Non Significant.</p