Figure 5. Promotion of in vivo neovascularization by transplantation of putative EPCs stimulated by Jag-1–mediated signals. A, Representative laser Doppler perfusion imaging findings in nude mice receiving PBS (no cells) or BM-Lin^– cells cocultured with empty-vector– or specific Notch ligand (Jag-1, Dll-1)–transfected 3T3 stromal cells at days 0 and 14 (upper panel). Hindlimb perfusion recovery was significantly enhanced in the Jag-1 group compared with the Dll-1, empty-vector, and PBS groups (n=6 per group, lower panel). *P<0.05 vs PBS; **P<0.01 vs PBS; ***P<0.001 vs PBS; P<0.05 vs vector; P<0.01 vs vector; P<0.05 vs Dll-1; P<0.01 vs Dll-1. B, Histological capillary density by isolectin B4 staining revealed augmented neovascularization in the Jag-1 group but not the Dll-1 group compared with the PBS group. *P<0.05; **P<0.01 (n=4 per group). HPF indicates high-power field. C, Histological density of putative EPCs (BM-Lin^– cells obtained from GFP transgenic mice) incorporating into vasculature of ischemic tissue. The density of the incorporating EPCs identified as CD31⁺/GFP⁺ cells was significantly greater in the Jag-1 group than in the Dll-1, empty-vector, and PBS groups. Green fluorescence indicates GFP; red signal, CD31. *P<0.05; **P<0.01 (n=4 per group).