Targeting macrophage-mediated clearance of apoptotic cells overcomes anti-VEGF resistance in choroidal...

Neovascular age-related macular degeneration (nAMD) is a leading cause of severe vision loss in the elderly worldwide. While anti-vascular endothelial growth factor (anti-VEGF) agents are the first-line standard of care, incomplete response to therapy (IRT) occurs in approximately 50% of patients. The microenvironmental factors driving IRT remain poorly understood. This study utilized Stereo-seq technology to construct a single-cell resolution spatial transcriptomic map (ST-map) of the retina-choroid-sclera (RCS) complex in healthy control mice, and in mice with laser-induced choroidal neovascularization (CNV) receiving either no treatment or anti-VEGF therapy. The study aimed to characterize spatial gene expression patterns and cell-cell interactions within the CNV microenvironment that may contribute to therapeutic resistance. The ST-map of the RCS complex identified distinct cellular compositions and gene expression profiles across conditions. In CNV lesions, anti-VEGF treatment induced significant shifts in the gene expression signatures of macrophages (MACs), endothelial cells (ECs), and fibroblasts (Fibros). Spatial analysis defined the proximity relationships within the neovascular niche, identifying specific macrophage-endothelial cell (MAC-EC) interactions implicated in lesion persistence. Specifically, macrophage depletion led to an accumulation of apoptotic ECs in anti-VEGF-treated lesions. In contrast, targeted blockade of CD47 in combination with anti-VEGF therapy enhanced the clearance of apoptotic ECs and achieved superior anti-angiogenic efficacy compared to anti-VEGF monotherapy. Spatial transcriptomics effectively identifies aberrant gene expression and intercellular communication networks within CNV microenvironment. These findings suggest that macrophage-mediated clearance of apoptotic cells plays a critical role in the response to treatment. Combining anti-CD47 agents with anti-VEGF therapy represents a promising strategy to overcome incomplete response and improve visual outcomes in nAMD.