Blockade of Platelet-Derived Growth Factor Signaling Inhibits Choroidal Neovascularization and Subretinal Fibrosis in Mice

Neovascular age related macular degeneration (nAMD) leads to severe vision loss worldwide and is characterized by the formation of choroidal neovascularization (CNV) and fibrosis. In the current study, we aimed to investigate the effect of blockade for platelet derived growth factor receptor-β (PDGFR-β) on the formation of choroidal neovascularization and fibrosis in the laser-induced CNV model in mice. Firstly, the presence of PDGFR-β in CNV lesions were confirmed. Intravitreal injection of PDGFR-β neutralizing antibody significantly reduced the size of CNV and subretinal fibrosis. Additionally, subretinal hyperreflective material (SHRM), a landmark feature on OCT as a risk factor for subretinal fibrosis formation in nAMD patients was also suppressed by PDGFR-β blockade. Furthermore, pericytes were abundantly recruited to the CNV lesions during CNV formation, however, blockade of PDGFR-β significantly reduced pericyte recruitment. In addition, PDGF-BB stimulation increased the migration of the rat retinal pericyte cell line, R-rPCT1, which was abrogated by the neutralization of PDGFR-β. These results indicate that blockade of PDGFR-β attenuates laser-induced CNV and fibrosis through the inhibition of pericyte migration.