Figure 3

Immunopositivity of endothelial cells differentiated from mesenchymal stem cells in the presence of VEGF-A for PECAM, vWF, and VE-cadherin. Representative grids for von Willebrand factor (vWF) are shown. Low-dose vascular endothelial growth factor (VEGF-A) induced a small increase in immunopositivity for platelet endothelial cell adhesion molecule-1 (PECAM-1), vWF, and vascular endothelial cadherin (VE-cadherin) (A, I). Higher concentrations of VEGF-A (25 to 50 ng/ml) induced a marked increase in expression of endothelial cell (EC) markers (B, C, I). Angiotensin II (Ang II; 2 to 50 ng/ml) had no effect on the expression of EC markers (D, E, F, I). Human umbilical vein endothelial cells (HUVECs) were used as an independent positive control showing ≈ 99% immunopositivity to vWF (G, I). Naïve MSCs were negative for EC marker expression (H, I). Graphical representation of the fluorescence-activated cell sorting (FACS) data (I). Note that HUVECs were excluded from the statistical analyses. *P <0.05 vs. naïve MSCs. ^# P <0.05 vs. VEGF-A (2 ng/ml). ^α P <0.05 VEGF-A (50 ng/ml) vs. VEGF-A (25 ng/ml)-treated MSCs, n = 3. MSC, mesenchymal stem cell.