A specific RIP3+ subpopulation of microglia promotes retinopathy through a hypoxia-triggered necroptotic mechanism

C He, Y Liu, Z Huang, Z Yang, T Zhou… - Proceedings of the …, 2021 - National Acad Sciences
C He, Y Liu, Z Huang, Z Yang, T Zhou, S Liu, Z Hao, J Wang, Q Feng, Y Liu, Y Cao, X Liu
Proceedings of the National Academy of Sciences, 2021National Acad Sciences
Retinal neovascularization is a leading cause of severe visual loss in humans, and
molecular mechanisms of microglial activation-driven angiogenesis remain unknown. Using
single-cell RNA sequencing, we identified a subpopulation of microglia named sMG2, which
highly expressed necroptosis-related genes Rip3 and Mlkl. Genetic and pharmacological
loss of function demonstrated that hypoxia-induced microglial activation committed to
necroptosis through the RIP1/RIP3-mediated pathway. Specific deletion of Rip3 gene in …
Retinal neovascularization is a leading cause of severe visual loss in humans, and molecular mechanisms of microglial activation-driven angiogenesis remain unknown. Using single-cell RNA sequencing, we identified a subpopulation of microglia named sMG2, which highly expressed necroptosis-related genes Rip3 and Mlkl. Genetic and pharmacological loss of function demonstrated that hypoxia-induced microglial activation committed to necroptosis through the RIP1/RIP3-mediated pathway. Specific deletion of Rip3 gene in microglia markedly decreased retinal neovascularization. Furthermore, hypoxia induced explosive release of abundant FGF2 in microglia through RIP3-mediated necroptosis. Importantly, blocking signaling components of the microglia necropotosis–FGF2 axis largely ablated retinal angiogenesis and combination therapy with simultaneously blocking VEGF produced synergistic antiangiogenic effects. Together, our data demonstrate that targeting the microglia necroptosis axis is an antiangiogenesis therapy for retinal neovascular diseases.
National Acad Sciences