hASC and hASC-CM preserve HPAEC transendothelial permeability. HPAEC were grown on polyester inserts (A-B) or on gold electrodes of ECIS arrays (C) in the absence/presence of NHDF/hASC (A), or NHDF/hASC conditioned media (B-C). HPAEC were removed from the contact with cells/media; then stimulated with 250 μM H2O2. T-test with Welch’s correction was used to assess the differences between analyzed groups. NHDF and NHDF-CM were used for comparison as a non-stem cell/conditioned media control. (C) Shown are the means of 3 parallel recordings for each pretreatment/stimulation: 1) unstimulated HPAEC pretreated with NHDF-CM; 2) unstimulated HPAEC pretreated with hASC-CM; 3) stimulated with H2O2 HPAEC which were not pretreated with CM; 4) stimulated with H2O2 HPAEC which were pretreated with NHDF-CM; 5) stimulated with H2O2 HPAEC pretreated with hASC-CM. Repeated measures One-way ANOVA showed significant differences between response of NHDF-CM-pretreated cells and response of ASC-CM pretreated cells. Preincubation of endothelial monolayers with hASC or hASC-CM reduced H2O2-induced hyperpermeability of HPAEC to FITC-dextran (A-B) or to ions (C).