Vascular endothelial growth factor and hepatocyte growth factor levels aredifferentially elevated in patients with advanced retinopathy of prematurity

Although the roles of vascular endothelial growth factor (VEGF) and hepatoc yte growth factor (HGF) in angiogenesis are well described, the putative ro les of these factors in retinopathy of prematurity (ROP) remain unknown We evaluated VEGF and HGF protein levels in subretinal fluid of eyes with ROP, and expression of their corresponding receptors in retrolental membranes a ssociated with stage 5 ROP, We examined subretinal fluid samples from eyes using rhegmatogenous retinal detachment as a control. VEGF and HGF were dif ferentially elevated in eyes with ROP, In Stage 5 ROP (n = 22), the mean VE GF and HGF levels were 14.77 +/- 14.01 ng/ml and 16.56 +/- 9.62 ng/ml, resp ectively. Interestingly, in patients with active stage 4 ROP, mean VEGF lev els were highly elevated (44.16 +/- 18.72 ng/ml), whereas mean HGF levels r emained very low (4.77 +/- 2.50 ng/ml). Next, we investigated is vivo expre ssion of VEGF receptor-2 and HGF receptor in retrolental membranes from 16 patients with stage 5 ROP. Both VEGF receptor-2 and HGF receptor proteins w ere detected mainly in posterior portions of the membrane as well as in ves sel walls and along the retinal interface where angiogenesis was active. Th ese findings together suggest that VEGF and HGF play important roles in the pathogenesis of ROP.