Human CD34+ cells isolated from umbilical cord blood were found to be capable of secreting several angiogenic factors, including VEGF, bFGF and hepatocyte growth factor (HGF) [18] and administration of these CD34+ cells after cerebral ischemia was shown to promote endogenous angiogenesis mainly due to the supply of these angiogenic factors [5]. This evidence concerns the gene HGF and brain ischemia.