The RPE and Recovery of the Blood Retina Barrier

总结： 视网膜色素上皮（RPE）是外神经视网膜和脉络膜之间的主要屏障， 形成血视网膜屏障（BRB）的一部分。对RPE细胞和RPE组织的损害 膜损害BRB，如在AMD、葡萄膜炎、视网膜变性和视网膜脱离中所见。此外，本发明还 在视网膜下手术或视网膜下注射后可发生对RPE的损伤。其他人的大量工作 与非眼上皮细胞单层的结合表明这些组织对应激作出反应并恢复其结构 并通过少量的保护机制发挥作用。我们初步的实验观察 这表明RPE对损伤或疾病的反应类似，通过可定义的保护作用恢复BRB。 机制等根据这些观察，我们假设：a）有有限数量的响应， RPE恢复BR B所需的时间; B）每种反应导致RPE细胞死亡的独特模式; c）每种 响应类型不同，因此BRB修复建模必须灵活（图1）。 出于这些原因，我们建议在这里测试RPE用于响应侮辱的特定机制， 在慢性轻度、中度和重度损伤后恢复BRB。在恢复屏障功能的同时 已经在果蝇翅膀、肺泡和整个胚胎学中进行了研究，但还没有在 RPE片。大多数关于上皮单层的研究，无论是在RPE中还是在非眼组织中，都使用2- 三维（2D）静态或延时运动显微摄影研究损伤反应。本课题 从外部视觉研究中采用聪明的软件和数学工具， (4D：3D在空间和1D在时间）动力学来探索单个RPE细胞的损伤反应和 RPE片。 意义：完成这些目标将增加我们对时空动力学的理解， BRB在短期或长期、低水平至高水平的RPE细胞毒性损伤后修复的生物力学。这 对机制的新理解将使我们能够纠正致盲过程中基本屏障功能的丧失 通过早期和廉价的干预措施来预防疾病。

Summary: The retinal pigment epithelium (RPE) is the major barrier between the outer neural retina and the choroid, forming part of the blood retina barrier (BRB). Damage to the RPE cell and to the organization of the RPE sheet impairs the BRB, as seen in AMD, uveitis, retinal degenerations, and retinal detachment. Additionally, damage to the RPE can occur following subretinal surgery or subretinal injections. Extensive work by others with non-ocular epithelial monolayers indicates that such tissues respond to stress and restore their structure and function through a small number of protective mechanisms. Our preliminary experimental observations suggest that the RPE similarly responds to damage or disease, restoring the BRB via definable protective mechanisms. From these observations, we hypothesize: a) There are a limited number of responses that the RPE takes to restore the BRB; b) Each kind of response results in a unique pattern of RPE cell death; c) Each response type differs, thus modeling BRB repair must be flexible (Fig 1). For these reasons, we propose here to test for specific mechanisms that the RPE uses to respond to insult and to restore the BRB following chronic mild, moderate, and severe injury. While restoration of barrier functions has been investigated in Drosophila wings, lung alveoli, and throughout embryology, it has not been studied in the RPE sheet. Most research on epithelial monolayers, whether in RPE or in non-ocular tissue, uses 2- dimensional (2D) static or time-lapse motion photomicroscopy to study damage responses. In this project, we adapt clever software and mathematical tools from outside vision research that use quantitative spatiotemporal (4D: 3D in space & 1D in Time) dynamics to explore the damage responses of individual RPE cells and of the RPE sheet. Significance: Completion of these Aims will increase our understanding of spatiotemporal dynamics and biomechanics of repair of the BRB after short- or long-term, low- to high-level toxic insults to RPE cells. This new understanding of mechanisms will allow us to correct the loss of essential barrier function in blinding diseases by initiating early and inexpensive interventions.