“…Transient vegf gene expression in vivo results in potent angiogenic sprouting, however, the resulting vasculature appears to be immature and leaky, similar to the results of VEGF protein delivery. (Rissanen et al, 2003) When vegf gene is co-administrated with genes encoding angiogenic maturation factors, such as pdgf-b (Hao et al, 2004a;Korpisalo et al, 2008;Kupatt et al, 2010) and ang-1 Siddiqui et al, 2003;Su et al, 2009), the vasculature is longer-lasting and less permeable,with increased perfusion, which is also similar to the results of dual protein growth factor delivery. Other genes delivered for stable vascular networks formation includes ang-1 (Shyu et al, 1998), pdgf-b (Shea et al, 1999, fgf-2 with pdgf-b (de Paula et al, 2009;Hao et al, 2004b), inf-β (Dickson et al, 2007, and neutrophin-3 (Cristofaro et al, 2010).…”