Figure 3.

Comparison of normal donor and SCLS HDMECs barrier function by using TEER. (A) Normal donor HDMECs and SCLS HDMECs demonstrate similar ECIS responses to stimulation with the G-protein–stimulating molecules histamine and thrombin. Data are from three experiments. There were no significant differences between normal donor and SCLS HDMECs. (B) There was a dramatic decrease in TEER (indicting increased permeability) in the SCLS HDMECs compared with normal donor HDMECs in response to stimulation with 10 ng/ml TNF. Significant differences between normal donor and SCLS HDMECs are noted at 4.5 h (*, P < 0.05). Data are from a collection of four separate experiments. (C) SCLS HDMECs demonstrate a prolonged barrier decrease in a dose-response relationship to TNF. Stimulation with all doses of TNF revealed increased permeability and delayed barrier recovery. Data are from two separate experiments (D) An ∼50% siRNA knockdown of p190BRhoGAP, assessed by immunoblotting, in normal donor HDMECs suggests p190BRhoGAP produces a similar dysfunction defect in barrier recovery as seen in the SCLS HDMECs by ECIS. Knockdown of the protein product of ARHGAP5, p190BRhoGAP by ∼50% with siRNA. Significant differences between nontargeting and ARHGAP5 siRNA-treated HDMECs are noted at 5 h. Data are from a collection from three experiments. (E) Viability and cell counts. Differences in TEER are not due to cell death (left) or cell number (right). There were no significant differences between cell types. Compiled data are from two experiments. Data are expressed as means ± SDs.