RP2 mutations cause a severe form of X-linked retinitis pigmentosa (XLRP). The mechanism of RP2-associated retinal degeneration in humans is unclear, and animal models of RP2 XLRP do not recapitulate this severe phenotype. Here, we developed gene-edited isogenic RP2 knockout (RP2 KO) induced pluripotent stem cells (iPSCs) and RP2 patient-derived iPSC to produce 3D retinal organoids as a human retinal disease model. Strikingly, the RP2 KO and RP2 patient-derived organoids showed a peak in rod photoreceptor cell death at day 150 (D150) with subsequent thinning of the organoid outer nuclear layer (ONL) by D180 of culture. Adeno-associated virus-mediated gene augmentation with human RP2 rescued the degeneration phenotype of the RP2 KO organoids, to prevent ONL thinning and restore rhodopsin expression. Notably, these data show that 3D retinal organoids can be used to model photoreceptor degeneration and test potential therapies to prevent photoreceptor cell death.

RP2突变会导致严重的 X 连锁色素性视网膜炎 (XLRP)。人类RP2相关视网膜变性的机制尚不清楚， RP2 XLRP 的动物模型不能重现这种严重的表型。在这里，我们开发了基因编辑的同基因RP2敲除 (RP2 KO) 诱导多能干细胞 (iPSC) 和RP2患者来源的 iPSC，以产生 3D 视网膜类器官作为人类视网膜疾病模型。引人注目的是，RP2 KO 和RP2患者来源的类器官在第 150 天 (D150) 显示视杆细胞感光细胞死亡峰值，随后培养第 180 天类器官外核层 (ONL) 变薄。腺相关病毒介导的人 RP2 基因增强挽救了 RP2 KO 类器官的变性表型，以防止 ONL 变薄并恢复视紫红质表达。值得注意的是，这些数据表明 3D 视网膜类器官可用于模拟光感受器变性并测试防止光感受器细胞死亡的潜在疗法。