Disrupting galectin-3 and NET-mediated microglia-neutrophil cross-talk suppresses pathological retinal angiogenesis.

Current research on pathological retinal neovascularization primarily focuses on growth factors, inflammation, and endothelial signaling pathways. However, increasing attention is being directed toward disruptions in the retinal immune microenvironment. Therefore, deciphering the immune-angiogenic interplay could uncover therapeutic avenues for neovascular disorders. Through integrative analyses of single-cell RNA sequencing from human fibrovascular membranes and multicohort clinical datasets, we identified neutrophil infiltration as an independent risk factor for diabetic retinopathy progression. Mechanistically, activated microglia preceded and potentiated neutrophil infiltration by secreting galectin-3 (GAL3), establishing a self-amplifying feedback loop that sustained microglial activation and drove pathological angiogenesis in mice with oxygen-induced retinopathy (OIR). To therapeutically disrupt this loop, we engineered a photocurable hydrogel for the sustained intravitreal delivery of GAL3 and vascular endothelial growth factor (VEGF)-neutralizing antibodies, which effectively suppressed aberrant angiogenesis in mice with OIR. Together, these findings reinforce the concept of retinal neovascularization as an immunovascular disorder and underscore the therapeutic potential of microenvironment-modulating strategies using biomaterials.