Nme2Cas9-mediated therapeutic editing in inhibiting angiogenesis after wet age-related macular degeneration onset

BackgroundAge-related macular degeneration (AMD), particularly wet AMD characterised by choroidal neovascularization (CNV), is a leading cause of vision loss in the elderly. The hypoxia-inducible factor-1 & alpha; (HIF-1 & alpha;)/vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) pathway contributes to CNV pathogenesis. Previous gene editing research indicated that disrupting these genes in retinal pigment epithelial cells could have a preventive effect on CNV progression. However, no studies have yet been conducted using gene editing to disrupt VEGF signalling after CNV induction for therapeutic validation, which is critical to the clinical application of wet AMD gene editing therapies. MethodHere, we employed the single-adeno-associated virus-mediated Nme(2)Cas9 to disrupt key molecules in VEGF signalling, Hif1 & alpha;, Vegfa and Vegfr2 after inducing CNV and estimated their therapeutic effects. ResultsWe found that Nme(2)Cas9 made efficient editing in target genes up to 71.8% post 11 days in vivo. And only Nme(2)Cas9-Vegfa treatment during the early stage of CNV development reduced the CNV lesion area by 49.5%, compared to the negative control, while Nme(2)Cas9-Hif1 & alpha; or Nme(2)Cas9-Vegfr2 treatment did not show therapeutic effect. Besides, no off-target effects were observed in Nme(2)Cas9-mediated gene editing in vivo. ConclusionsThis study provides proof-of-concept possibility of employing Nme(2)Cas9 for potential anti-angiogenesis therapy in wet AMD.