Pluripotent Stem Cell Derived 3D Retinas for Studies of Early Onset Retinal Degeneration

项目概要/摘要： 视网膜变性（RD）疾病，如视网膜色素变性（RP）和Leber先天性黑蒙 (LCA)引起感光细胞（PR）的功能障碍和细胞死亡，最终导致失明。 虽然不被经典地认为是视网膜变性，但阿尔茨海默病（AD）也表现出许多 遗传性视网膜退化的标志在AD和遗传性光感受器退化中，例如 LCA，激活的小胶质细胞与营养不良区域密切相关，在那里它们参与 神经炎症过程。资助父母补助金的最初目的是研究以下方面的作用： AIPL 1突变在早发性视网膜变性发病中的作用虽然这无疑会揭露许多 关于这种使人衰弱的疾病的发病机制的有趣发现，这个模型缺乏一个关键因素， 是在体内发现的，即小胶质细胞的存在。除了在手术过程中为视网膜分层提供支持外， 在发育过程中，小胶质细胞也参与神经炎症过程。在目前的提案中，我们将 在我们现有的LCA模型基础上，将小胶质细胞纳入开发的3D视网膜类器官中， 其将更具生理性，并且能够在体内发生的RD期间响应死亡细胞。 此外，我们将包括阿尔茨海默氏症患者来源的iPSC来构建3D视网膜，以基于 营养不良这是非常重要的，因为如果小胶质细胞在不同形式的RD中发挥类似的作用， 会给我们一个共同的分子目标我们提出的小胶质细胞工作与 由于将小胶质细胞整合到我们现有的3D视网膜模型中， 不仅是我们正在进行的LCA研究，而且还将使我们能够分支到一个新的研发模式， 老年痴呆症中心假设是人PSC衍生的具有LCA和AD的3D视网膜类器官 相关突变将重演人类视网膜营养不良，导致PR丢失，小胶质细胞增多， AD特征性标志物的激活和积累。虽然研究LCA组织中的小胶质细胞本身 值得注意的奋进，以类似的方式探索AD组织将增加关于一般AD的重要信息。 小胶质细胞对细胞应激和细胞死亡的反应。该提案将连接两项创新技术;（1） 3D视网膜类器官技术和（2）干细胞衍生的小胶质细胞的定向分化。鉴于 小胶质细胞在神经退行性疾病中的参与这个项目非常适合于阐明 LCA和AD的机制。这些研究不仅将导致对RD生物学的新见解， 疾病，但它也可以提供一个模型，探索新的治疗靶向小胶质细胞， 我们的工作范围从狭隘的视网膜研究到更广泛适用的研究， 神经退行性疾病，如阿尔茨海默病和LCA。

Project Summary/Abstract: Retinal degenerative (RD) diseases, such as Retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA), cause dysfunction and cell death of photoreceptor (PR) cells, ultimately leading to blindness. While not classically considered a retinal degeneration, Alzheimer’s disease (AD) also exhibits many hallmarks of hereditary retinal degenerations. In both AD and hereditary photoreceptor degenerations, like LCA, activated microglia are intimately associated with dystrophic regions where they participate in neuroinflammatory processes. The original AIMs of the funded parent grant sought to study the role of AIPL1 mutations in the onset of early onset retinal degeneration. While this will no doubt uncover many fascinating findings about the pathogenesis of this debilitating disease, this model is lacking a key element that is found in vivo, namely the presence of microglia. In addition to providing support for retinal lamination during development, microglia also participate in neuroinflammatory processes. In the current proposal we will build upon our existing LCA model by incorporating microglia into developing 3D retinal organoids which will be more physiologic and capable of responding to dying cells during RD as occurs in vivo. Furthermore, we will include Alzheimer’s patient derived iPSCs to build 3D retinas to model AD based dystrophy. This is extremely important because if microglia serve a similar role in different forms of RD this would give us a common molecular target. Our proposed microglia work is highly synergistic with the AIMs of the original grant since integrating microglia into our existing 3D retina model will enhance not only our ongoing LCA studies but also will enable us to branch out into a new model of RD based on Alzheimer’s disease. A central hypothesis is that human PSC derived 3D retina organoids with LCA and AD associated mutations will recapitulate human retinal dystrophy resulting in PR loss, increased microglial activation and accumulation of markers characteristic of AD. While studying microglia in LCA tissue by itself is a noteworthy endeavor, exploring AD tissue in a similar fashion will add important information on general responses of microglia to cell stress and cell death. This proposal will bridge two innovative technologies; (1) 3D retinal organoid technology and (2) directed differentiation of stem cell derived microglia. Given the involvement of microglia in a host of neurodegenerative disorders this project is highly appropriate to elucidate the mechanisms of both LCA and AD. Not only will these studies lead to new insights into the biology of RD disease, but it could also provide a model to explore new therapeutics targeting microglia which would expand the scope of our work from narrowly focused retinal studies to more broadly applicable studies of neurodegenerative disorders like Alzheimer’s disease and LCA.