Mapping angiogenesis on choroidal membranes of a murine laser induced CNV model

English (OpenAlex)

Abstract Purpose We investigated the expression and distribution of neoangiogenic molecules during the development of choroid neovascular (CNV) lesions in a laser‐induced mouse model of neovascular age‐related macular degeneration (AMD), with particular focus on the choroid of these lesions. Methods Lesions were induced on C57BL/6 mice using laser photocoagulation. Animals were sacrificed and eye‐cups were dissected from enucleated eyes, and the choroids were shortly fixed. Choroids were immunostained for NG2 (pericytes), VEGFR2 (vascular endothelial growth factor receptor 2; sprouting endothelial cells(ECs)), or VEGF with co‐staining for CD31 (vascular ECs). lmages of the choroidal membranes were obtained by microscopy. Vascular permeability was also determined. Results CNV lesions displayed positive staining for the four angiogenic markers studied. The distributions of the angiogenic markers were determined in comparison to the area of neovascularization, as observed by increased CD31 staining. Both NG2 and VEGFR2 displayed a radial progression, while VEGF displayed a uniform distribution across the choroidal membranes of the lesions in the studied times. Vascular permeability showed an increase concomitant with the increase in vascularization observed by immunostaining throughout the time‐course. Conclusion Our data shows that the choroidal membranes of CNV lesions recover through a canonical sprouting angiogenesis pathway, in response to a VEGF‐mediated signal. ln addition, these membranes display an increasing radial endothelial sprouting with concomitant pericyte recruitment from the laser injury to the exterior of the lesions, in a time‐dependent. These results may have implications for the clinical understanding of CNV in patients with wet AMD.