Novel targets for gene therapy in diabetic retinopathy (DR)

糖尿病影响着全球8.5%的18岁以上成年人。其中三分之一被诊断患有糖尿病视网膜病变（DR），使其成为工作年龄成年人失明的主要原因。DR的根本原因很难纠正，需要数年或数十年的治疗。DR的特征最近与Müller细胞中的早期神经胶质变化有关。这些重要的视网膜大胶质细胞对神经元有许多支持功能，并作为视网膜神经血管单位内的中心连接元件。特别是，它们有助于维持在DR中受损的血-视网膜屏障（BRB），导致经常观察到的血管通透性增加。因此，Müller细胞的胶质细胞变化被认为促进了DR的进展。由于DR的小鼠模型缺乏重要的视网膜结构，例如富含视锥细胞的黄斑区，因此猪提供了更好的平移模型，其富含视锥细胞的中央视网膜区域更准确地类似于人类解剖结构。此外，遗传性胰岛素缺乏的INSC 94 Y模型重现了DR病理学的关键特征，因此我们的目标是在这种大型I型糖尿病动物模型中恢复Müller细胞的稳态功能。该项目将开发一种基于AAV的基因治疗方法来重新编程Müller细胞代谢，并在INSC 94 Y猪的体外和体内进行测试。DCas 9-VPR介导的Müller细胞中关键代谢基因的过表达有望增强糖尿病视网膜中Müller神经胶质细胞的稳态功能，从而改善DR中的神经元存活和BRB完整性。

Diabetes affects 8.5% of adults over the age of 18 worldwide. One-third of these are diagnosed with diabetic retinopathy (DR), making it the leading cause of blindness in working-age adults. The underlying causes of DR are difficult to correct and require treatment for years or decades. The hallmarks of DR have recently been linked to early gliotic changes in Müller cells. These important retinal macroglial cells have many supportive functions for neurons and act as a central connecting element within the retinal neurovascular unit. In particular, they help maintain the blood-retinal barrier (BRB), which is impaired in DR, leading to the increased vascular permeability often observed. Therefore, gliotic changes in Müller cells are thought to promote the progression of DR. Since mouse models for DR lack important retinal structures such as the cone rich macular region, the pig offers a better translational model with a cone-rich central retinal area more acurately resembling the human anatomy. Moreover, the genetic insulin deficient INSC94Y model recapitulates key hallmarks of DR pathology and therefore we aim to restore the homeostatic functions of Müller cells in this large animal model of type I diabetes. The project will develop an AAV-based gene therapy approach to reprogram Müller cell metabolism and test it in vitro and in vivo in the INSC94Y pig. The dCas9-VPR-mediated overexpression of key metabolic genes in Müller cells is expected to enhance the homeostatic function of Müller glial cells in the diabetic retina, thereby improving neuronal survival and BRB integrity in DR.