Hepatocyte growth factor in vitreous fluid of patients with proliferative diabetic retinopathy and other retinal disorders

OBJECTIVE - To determine whether hepatocyte growth factor (HGF) is elevated in the vitreous fluid of patients with proliferative diabetic retinopathy (PDR). RESEARCH DESIGN AND METHODS - Vitreous fluid samples were obtained at the time of vitreoretinal surgery from 73 eyes of PDR patients and from 17 eyes of nondiabetic patients (control subjects) who had macular hole, rhegmatogenous retinal detachment, or epiretinal membrane (9, 4, and 4 eyes, respectively) but no associated proliferative vitreoretinopathy. Stages of PDR were classified as active or quiescent. Concentrations of HGF and vascular endothelial growth factor (VEGF) in vitreous fluid were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS - Intravitreous concentrations of HGF (median [range]) were significantly higher in diabetic patients with PDR (6.00 ng/ml [0.75-22.2]) than in control patients (2.86 ng/ml [0.75-5.80]). Intravitreous concentrations of VEGF were also higher in diabetic patients with PDR (1.62 ng/ml [0.15-7.9]) than in control patients (0.16 ng/ml [0.16-0.29]). Both VEGF and HGF concentrations were significantly higher in patients with active retinopathy than in those with quiescent retinopathy. However, vitreous concentrations of HGF were unrelated to those of VEGF: CONCLUSIONS - We found that levels of HGF in vitreous fluid of PDR patients are significantly higher than in nondiabetic patients and that the levels of HGF are elevated in the active PDR stage. This suggests that HGF stimulates or perpetuates neovascularization in PDR.