Tian Zhou, Ziqi Yang, Hong Zhou, Biyan Ni, Yang Zhou, Jingpeng Li, Minglu Ma, Huaicheng Wang, Peng An, Huiyi Xu, Xiaojing Lin, Shiya Lin, Shasha Wang, Shida Chen, Lixia Lin, Xialin Liu, Chang He
Microglia are central regulators of retinal immune homeostasis, yet their pathogenic states in retinal degeneration remain less well understood. Here we identified a distinct subset of lipid-accumulated reactive microglia (aLARM), using scRNA sequencing and spatial transcriptomics in NaIO3-induced retinal degeneration mice, predominantly localized to the outer retina. aLARM were conserved across mouse models and patients and uniquely marked by high CD36 expression. Microglia-specific CD36 deletion abolished aLARM-mediated inflammation and degeneration, whereas subretinal transplantation of CD36+ aLARM exacerbated retinal structural destruction and functional impairment. Mechanistically, CD36+ aLARM activated NLRP3 inflammasome and produced IL-1β, engaging IL-1R1 on microglia/macrophages and pericytes/SMCs to amplify a feed-forward inflammatory circuit. Therapeutic CD36 blockade with the neutralizing antibody FA6-152 reduced aLARM formation and protected against neurodegeneration. Together, our findings highlight CD36+ aLARM as a targetable pathogenic microglial population linking neuroinflammation to retinal degeneration, providing a potential foundation for microglia-based precision therapies.