Programming retinal Müller glial cells for supporting neuronal survival in retinal degeneration

对视网膜穆勒胶质细胞进行编程以支持视网膜变性中神经元的存活

• 批准号: 399415314
• 负责人: Professorin Dr. Cornelia Deeg
• 金额: --
• 依托单位: Lehrstuhl für Tierphysiologie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/399415314?language=en
• 关键词: Programming; retinal; ller; glial; cells

Inherited retinal dystrophies (IRD) are rare disorders of the retina that cause degeneration of photoreceptors and thus result in severe decline of visual ability for the affected patients. The causative mutations driving IRD are extremely complex covering so far more than 200 known genes. Since only a smaller fraction of those mutations affect cone photoreceptors, while on the other hand, cones are the main photoreceptor cell type used in daylight vision, an important therapeutic concept is to preserve cone function independent of developing corrective gene therapies for any underlying mutation. Many neuroprotective factors effective against photoreceptor degeneration have been identified and most of them are normally provided by retinal Müller glial cells (RMG), the main glial cell of the retina, for preserving photoreceptor function throughout life. However, under IRD conditions, the intrinsic support provided by RMG is insufficient and we hypothesize that boosting the neuroprotective properties of RMG will prolong photoreceptors survival and retinal function in IRD.We aim to achieve this by CRISPR/(d)CAS9-driven re-programming of RMG into a neuroprotective phenotype and simultaneously suppressing adverse glial responses by interfering with gliotic/immune responses. We will focus on four different neurotrophic factors, namely, CNTF and GDNF, which both represent the as yet most effective neuroprotective factors in IRD. Further we will include CXCL10, a novel RMG-derived neurotrophic factor that we previously validated for a direct pro-survival effect on photoreceptors and finally, we will explore RdCVF, a rod-derived neurotrophic factor that was found to directly support cone survival, but is not naturally expressed by RMG. The models we will be using are primary RMG isolated from pigs as well as organotypic retinal explants, which will enable to target RMG in the intact tissue context. The final goal of this project is development of a pro-survival phenotype of RMG within the intact tissue context by simultaneous activation of pro-survival protein expression and inhibition of gliotic/inflammatory reactions.This will provide a completely novel and mutation-independent therapeutic strategy that might overcome previous limitations of neuroprotective therapy and eventually prevent disease progression and thus preserve fragile photoreceptors before corrective gene therapy or gene addition therapy becomes available for the individual patient. It also could be envisioned to be applicable to patients, which have already lost all rod photoreceptors and hence are too far progressed for corrective gene therapy, but still have residual cone-driven vision, which could be preserved. Further, this therapy may also be applicable beyond IRD to other degenerative diseases of the retina, such as glaucoma, age-related macular degeneration and diabetic retinopathy.

遗传性视网膜营养不良（IRD）是一种罕见的视网膜疾病，会导致光感受器变性，从而导致受影响患者的视力严重下降。导致IRD的致病突变非常复杂，迄今为止涵盖了200多个已知基因。由于这些突变中只有一小部分影响视锥光感受器，而另一方面，视锥是日光视觉中使用的主要感光细胞类型，因此重要的治疗概念是保持视锥功能，而不依赖于开发针对任何潜在突变的矫正基因疗法。已经鉴定出许多有效对抗光感受器变性的神经保护因子，并且它们中的大多数通常由视网膜的主要神经胶质细胞视网膜Müller神经胶质细胞（RMG）提供，用于在整个生命过程中保护光感受器功能。 然而，在IRD条件下，RMG提供的内在支持是不够的，我们假设增强RMG的神经保护特性将延长IRD中的光感受器存活和视网膜功能。我们的目标是通过CRISPR/（d）CAS9驱动的RMG重编程为神经保护表型，同时通过干扰胶质细胞/免疫反应来抑制不良胶质细胞反应。我们将集中在四个不同的神经营养因子，即，CNTF和GDNF，这两个代表迄今为止最有效的神经保护因子在IRD。此外，我们将包括CXCL 10，一种新的RMG衍生的神经营养因子，我们以前验证了对光感受器的直接促生存作用，最后，我们将探索RdCVF，一种杆源性神经营养因子，被发现直接支持视锥细胞存活，但RMG不自然表达。我们将使用的模型是从猪中分离的原发性RMG以及器官型视网膜外植体，这将使得能够在完整的组织背景下靶向RMG。该项目的最终目标是通过同时激活促生存蛋白表达和抑制胶质/炎症反应，在完整组织背景下开发RMG的促生存表型。一种独立的治疗策略，可以克服以前神经保护治疗的局限性，并最终阻止疾病进展，从而在纠正基因治疗之前保护脆弱的光感受器。治疗或基因添加治疗变得可用于个体患者。还可以设想其适用于已经失去所有视杆细胞光感受器的患者，因此对于矫正基因治疗来说进展太大，但仍然具有可以保留的残余视锥驱动视力。此外，这种疗法也可以在IRD之外适用于其他视网膜变性疾病，例如青光眼、年龄相关性黄斑变性和糖尿病视网膜病变。