NGF and NGF-receptor expression of cultured immortalized human corneal endothelial cells

PURPOSE Several growth factors, including nerve growth factor (NGF) and vascular endothelial growth factor (VEGF), play an important role in the homeostasis of the ocular surface. The involvement of both these growth factors in the pathophysiology of intraocular tissues has been extensively investigated. Despite the expression of NGF receptors by corneal endothelium, to date the role of NGF on the endothelial cell remains to be determined. Using a clonal cell line of human corneal endothelial cells, the aim of this study was to investigate the expression of the NGF-receptor and the potential partnership of NGF and VEGF in maintaining cell viability in vitro. METHODS A human endothelial cell line (B4G12), was cultured under serum-free conditions as previously described with and without addition of different concentrations of NGF, anti-NGF-antibody (ANA), or VEGF for 4 days and these cells were used for immuno-istochemical, biochemical, and molecular analyses. RESULTS NGF induces overexpression of NGF-receptors and synthesis and release of VEGF by endothelial cells and these cells are able to produce and secrete NGF. CONCLUSIONS These observations indicate that human corneal endothelial cells are receptive to the action of NGF and that these cells may regulate NGF activity through autocrine/paracrine mechanisms.