Flow cytometric analysis of surface markers on bone marrow cells (CD31+, CD34+, CD133+, CXCR4+, C-kit, CD26) and identification of endothelial progenitor cells (EPCs) through double staining of C-kit/CD31 at 18 hour after CLI procedure. Except for CD26+ cells, significantly higher numbers of EPCs in BM of DPP4-deficient rats regardless of GCSF treatment than that in wild-type Fischer rats with or without GCSF treatment. For comparison among the four groups, statistical analysis by one-way ANOVA. * vs. other groups, P < 0.0001. Symbols (*, †, ‡, §) indicate significant difference (at 0.05 level) by Bonferroni's multiple-comparisons post hoc test (n = 6 per group).