Distribution of CXCR4+ cells in ischemic skeletal muscle on day 14 following CLI induction. A to F) Immunofluorescent staining of CXCR4+ cells (white arrows) in ischemic skeletal muscle on post-CLI Day 14 with nuclei being counter-stained with DAPI (blue) (400x, n = 6 per group). G) In DPP4-deficient animals, significantly higher number of CXCR4+ cells in those with or without GCSF treatment than in DPP4D-NC, with no between the former two groups. * vs. †, P < 0.01. In WT Fischer rats, notably higher number of positively-stained cells in those with GCSF treatment than in those without and WT-NC, and higher in the WT-CLI group than in WT-NC. * vs. †, P < 0.0001. For comparison among the six groups, statistical analysis by one-way ANOVA. * vs. other groups, P < 0.0001. Symbols (*, †) indicate significant difference (at 0.05 level) by Tukey's multiple comparison procedure.