Figure 6

IFN-β downregulates VE-cadherin and increases permeability of human brain endothelial cells. (A) Human brain endothelial cells from the hCMEC/D3 cell line were treated with different doses of IFN-β as indicated for 24 h and western blot analysis of total lysates was performed to determine the expression of junction proteins. The immunoblots shown are representative of three independent experiments. VE-cadherin levels are substantially decreased in a dose-dependent manner and the decrease is quantified by NIH image J software. β-Actin is used as a loading control and the data is quantified in (B). Original blot is presented in Supplementary Fig. S7. (C) VE-cadherin levels were quantified by quantitative RT-PCR in hCMEC/D3 cells after IFN-β (100 ng/ml) stimulation for indicated time points. (D) IFN-β treatment dose dependently increased the leak of 40 KDa FITC-dextran through the monolayer of endothelial cells. Data represent the mean ± SD of three independent experiments. Statistical analysis was performed by one-way ANOVA followed by Tukey’s multiple comparisons test. **p = 0.0078, **p = 0.0035, **p = 0.0022; ****p = 0.0001; **p = 0.0082, **p = 0.0029, ***p = 0.0009; respectively. ns non-significant.