The Effect of Soluble EphrinB4 Receptor on Laser–Induced Choroidal Neovascularization

Abstract

Abstract: : Purpose: EphB4 receptor and its ligand (EphrinB2) are critical regulators of vascular assembly. Recombinant soluble form of EphB4 extracellular domain (sEphB4) inhibits vessel maturation and angiogenesis. The purpose of this study was to evaluate the effect of intravitreal injection of sEphB4 receptor on the pathogenesis of laser induced choroidal neovascularization (CNV). Methods: Focal laser photocoagulation (Diode green laser, 170 mW, 0.05 s, 75 microns) was applied to Brown Norway pigmented rats. Four laser burns were created in the posterior pole of each retina. sEphB4 (0.1, 0.3, 1 or 3 micrograms), or vehicle was injected into the vitreous, 3 and 7 days after laser photocoagulation. Fluorescein angiograms (FA) and histological examinations were performed at day 14 after laser surgery. Results: sEphB4 injection resulted in a dose–response inhibition of leakage during FA. At the highest dose, leakage was almost completely blocked. Preliminary histological studies reveal that eyes injected with the highest dose of sEphB4 show decreased vascularity in the CNV lesions. Conclusions: CNV was inhibited by the injection of s ephB4 in rat vitreous. This study suggests that sEphB4 receptor and its ligand are involved in the development of CNV and should be further investigated as a therapeutic target.

Keywords: age–related macular degeneration • choroid: neovascularization • cell adhesions/cell junctions