Inhibition of neointimal proliferation by EPC transplantation in injured carotid arteries. (A) H & E staining of injured arteries or sham group. Scale bar = 100 μm. (B) Quantified intima area. (C) Quantified media area. (D) Neointima/media ratios. * P <0.05, # P <0.01, ** P <0.001; NS, not significant, n = 4. EPC, endothelial progenitor cells.