Fig. 3
Prolonged Hypoxia impairs the barrier function in both cell monolayers. TEER (a) and sodium fluorescein (b) permeability values in both iPSC-BMECs and hCMEC/D3 cell monolayers following exposure to hypoxia for 6 and 24 h. Note the early onset of hypoxia-induced barrier disruption in hCMEC/D3 at 6 h as indicated by TEER compared to IMR90-derived BMECs, with a significant decrease at 24 h. Hypoxia-induced paracellular permeability however was only observed after 24 h in both groups. c Immunocytochemistry profile of IMR90-derived BMECs following exposure to hypoxia (1 % O2) for 24 h. Note the decreased immunoreactivity of claudin-5 and occludin following hypoxia, whereas no changes where noted in other cell junction proteins (β-catenin and PECAM-1). Scale bar = 20 µm. d Cell metabolic activity as measured by MTS assay. Following hypoxic incubation, MTS was added to the cell conditioned medium and incubated for 1 h before readout. Mean ± SD, n = 3 for each group. * and ** denotes P < 0.05 and P < 0.01 to controls (labeled as 0 h) respectively