Quantification of immunofluorescent (IF) (400x) and immunohistochemical (IHC) (200x) staining for ischemic quadriceps by day 21 following CLI procedure (n = 8). A to E) showing the IF stain of CD31+ cells (white arrows) in five groups (A = control, B = CLI only, C = CLI + cilostazol, D = CLI + clopidogrel, E = CLI + combined therapy). F)* vs. other groups with different symbols, p < 0.0001. Nuclei (blue color) stained with 4’,6-diamidino-2-phenylindole (DAPI) as counter staining. The scale bars in right lower corner represent 20 μm. G to K) indicating the results of IHC stain of von Willebrand factor (vWF) + cells (red arrows) in five groups (G = control, H = CLI only, I = CLI + cilostazol, J = CLI + clopidogrel, K = CLI + combined therapy). L)* vs. other groups with different symbols, p < 0.0001. The scale bars in right lower corner represent 50 μm. CLI = critical limb ischemia; Cil = cilostazol; Clo = clopidogrel.