Intriguingly, hosts exhibited a spontaneous upregulation of VEGF, bFGF, HGF and SDF-1α on day 3 and day 7 when compared to day 0 (P<0.05 within control group, respectively), indicating some degree of endogenous angiogenic factors mobilization in response to hindlimb ischemia. The gene discussed is CXCL12; the disease is ischemia.