Fig. 3.

S protein induces the expression of myofibrogenic markers in pericytes. A) Western blot analysis shows that expression of the pro-fibrotic protein fibronectin in human brain vascular pericytes is induced upon S protein exposure at 10 nM for 6 h. B) Western blot analysis shows that fibronectin expression in brain pericytes continues to increase after S protein exposure at 15 nM for 24 h. C) Representative images of immunofluorescence staining that illustrate the expression pattern of fibronectin in brain pericytes in a dose-dependent manner upon exposure to S protein for 24 h. D) Western blot analysis shows that expression of the fibrogenic protein NOTCH3 in brain pericytes remains unchanged after S protein exposure for 6 h, despite slight statistically non-significant increase at 5 and 10 nM. E) Western blot analysis shows that NOTCH3 expression in brain pericytes increases upon exposure to 10 and 15 nM S protein for 24 h. F) Representative images of staining that illustrates NOTCH3 expression pattern in brain pericytes in a dose-dependent manner upon exposure to S protein for 24 h, outlining a possible aggregation at the cell membrane in response to an elevated dose of S protein at 15 nM (white arrowheads). Data are mean ± SEM (n = 3 independent experiments/ condition). *P < 0.05 compared with vehicle-treated pericytes (two-tailed unpaired t-test). Vehicle, ddH₂O; 6H, 6  hours; 24H, 24  hours.