Fig. 3

Human umbilical vein cord endothelial cell (HUVEC) proliferation. a Cell proliferative activity monitored in real time using xCELLigence system. b, c Representative graphs showing difference in mean cell index value (b) and slope of the line (c) between each selected time period (12–24, 24–48 and 48–72 h). HUVECs treated with human dental pulp stromal cell conditioned medium (hDPSC-CM), independent of concentration, proliferated significantly faster than other groups at all time periods. d MTT assay showing significantly enhanced proliferation of HUVECs in hDPSC-CM compared with EGM-2 at 3 days. e, f mRNA expression of the proliferative biomarkers antigen KI-67 (Ki67) and proliferating cell nuclear antigen (PCNA) in HUVECs at 2, 3 and 7 days. Endothelial growth medium (EGM-2) group served as reference for comparison. Data presented as mean ± SEM. *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, n = 4. EBM-2 Endothelial Basal Medium-2, CM conditioned medium, EGM-2 Endothelial Growth Medium-2, MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, d days