Overcoming Barriers to retinal ganglion cell replacement in experimental glaucoma

项目总结/摘要 视网膜神经节细胞（RGC）是视网膜负责传递信息的输出神经元 从眼睛到大脑的视觉世界。因此，RGC损伤和损失，许多疾病的特征， 的视觉系统，有视力障碍的直接后果，或失明时，RGC损失更多 严重。我们的预防方法建立在一个非常完善的，彻底的特点， 验证的实验性青光眼（EG）模型。这为我们的研究提供了独特的优势， 在研资局退变的可靠模型框架内， 其紧密地概括了在人类中观察到的解剖学变化和病理生理学过程， 青光眼此外，我们的初步结果建立了我们的方法的可行性，表明我们有 已经成功地将人诱导多能干细胞（iPSC）衍生的RGC移植到 EG视网膜，同时也表征了需要有针对性的解决方案的主要障碍。因此，我们建议 对供体RGC和受体EG视网膜进行一系列操作，以克服 现有的障碍，以取代研资局，从而使巨大的飞跃，实现大胆的 目的是恢复因青光眼或其他视神经病变而失明的人的视力。我们的每个目标都是正确的 基于相关生物学的现有知识，并将导致捐助者研究资助委员会的有意义的增强 在脑水肿EG视网膜中的存活、整合和功能。我们将利用严格的定量 电生理学和解剖学评估，以检验每个目标的核心假设。目标1将 靶向神经炎症以改善移植的RGC的长期存活。我们将创建 低免疫原性iPSC和操纵宿主视网膜环境使用全身免疫抑制 试剂或抑制小胶质细胞活化。Aim 2将通过以下途径增加供体细胞的存活和整合： 细胞年龄的调节，通过细胞凋亡实验性诱导宿主视网膜胶质细胞至未成熟状态， 复兴前程的目的3将增强供体RGCs在视网膜中的连接性和轴突生长。捐助方区域政府理事会 将被编辑以表达用于化学发生刺激的hM 3Dq DREADD受体和mTOR激活剂。 血小板反应蛋白将在宿主视网膜星形胶质细胞和供体RGC中过表达，从而利用星形胶质细胞衍生的血小板反应蛋白。 促进轴突生长和突触发生的因子。总之，这些目标将产生丰富的 为科学界提供知识和资源，使我们更接近现实的愿景 通过RGC替换。

Project Summary / Abstract Retinal ganglion cells (RGCs) are the output neurons of the retina responsible for transmitting information about the visual world from the eye to the brain. Thus, RGC damage and loss, a characteristic of many disorders of the visual system, has the direct consequence of vision impairment, or blindness when RGC loss is more severe. Our translation-enabling approach builds on a very well-established, thoroughly characterized and validated experimental glaucoma (EG) model. This affords our study the distinct advantage of conducting each of the proposed hypothesis-driven experiments within the framework of a reliable model of RGC degeneration that closely recapitulates the anatomical changes and pathophysiological processes observed in human glaucoma. Moreover, our preliminary results establish the feasibility of our approach, demonstrating that we have already achieved successful transplantation of human induced pluripotent stem cell (iPSC)-derived RGCs into the EG retina, while also characterizing major barriers that require targeted solutions. Hence, we propose to employ a series of manipulations to both donor RGCs and the recipient EG retina in order to overcome the existing barriers to RGC replacement and thus make a giant leap forward toward realization of the audacious goal to restore vision in persons blinded by glaucoma or other optic neuropathies. Each of our Aims is soundly based on existing knowledge of the relevant biology and will lead to meaningful enhancement of donor RGC survival, integration, and function in the glaucomatous EG retina. We will utilize rigorous quantitative electrophysiological and anatomical assessments for testing the hypothesis at the core of each Aim. Aim 1 will target neuroinflammation to improve the long-term survival of transplanted RGCs. We will create hypoimmunogenic iPSCs and manipulate the host retinal environment using systemic immunosuppressive agents or inhibition of microglial activation. Aim 2 will augment donor cell survival and integration through modulation of cellular age, with host retinal glia experimentally induced to an immature state through cellular rejuvenation. Aim 3 will enhance the connectivity and axon outgrowth of donor RGCs in the retina. Donor RGCs will be edited to express hM3Dq DREADD receptors for chemogenetic stimulation and mTOR activators. Thrombospondin will be overexpressed in host retinal astrocytes and donor RGCs, leveraging astrocyte-derived factors that promote axonal outgrowth and synaptogenesis. Together, these Aims will generate a wealth of knowledge and resources for the scientific community and bring us significantly closer to the reality of vision restoration through RGC replacement.