Delineating the role of TIMP3 in macular degeneration

摘要 视网膜色素上皮-脉络膜毛细血管（RPE-CC）复合体是视网膜色素变性的主要发病部位。 几种眼睛疾病，包括年龄相关性黄斑变性（AMD）和相关的黄斑营养不良，如 Sorsby眼底营养不良（SFD）。值得注意的是，金属蛋白酶组织抑制剂3的RPE下积累 TIMP3是SFD/AMD的显著特征。然而，不知道"如何"亚RPE TIMP 3积累 促进SFD/AMD病理学。这部分是因为RPE-CC是一种功能性复合材料， 研究在体内疾病发展期间RPE相对于CC层的空间变化的贡献。 此外，体外RPE-CC的代表性模型的缺乏显著影响了我们的能力， 体外研究RPE与CC相互作用。使用诱导多能干细胞（iPSC），我们已经开发了一种iPSC- RPE-CC模型概括了健康和AMD/SFD眼睛的关键特征。具体而言，iPSC-RPE-CC 显示有孔CC样脉管系统和Bruch膜样ECM的证据。类似地，SFD iPSC-RPE- CC显示SFD/AMD的两个中心标志，玻璃疣和脉络膜新血管形成（CNV）样病理。 值得注意的是，对照与SFD iPSC模型的纵向分析显示，亚RPE TIMP 3积累 发生相对较早并且先于黄斑病变细胞事件。此外，我们初步的概念证明 研究表明，SFD iPSC模型中RPE下TIMP3的积累促进了前黄斑病变细胞 脂质代谢失调和无菌性炎症引起的变化。基于这些强有力的初步研究， 该建议的总体目标是建立亚RPE TIMP 3积累对视网膜色素变性的独立贡献。 AMD/SFD病理学发展。我们将执行空间（RPE与CC）和时间（例如，之前和之后 玻璃疣形成）在i）SFD iPSC-RPE-CC和ii）对照iPSC-RPE-CC中TIMP 3表达/活性的操纵。 CC培养物（来源于具有正常视力的健康受试者的iPSC）以测试亚RPE TIMP 3 累积导致脂质代谢失调和无菌炎症，并因此i）玻璃疣 在RPE单层下方和ii）CC萎缩和CNV。从治疗的角度来看，我们将 在SFD/AMD iPSC模型中靶向失调的脂质代谢和无菌炎症。

ABSTRACT The retinal pigment epithelium-choriocapillaris (RPE-CC) complex is the primary site of disease pathogenesis in several eye diseases, including age-related macular degeneration (AMD) and related macular dystrophies, like Sorsby’s fundus dystrophy (SFD). Notably, sub-RPE accumulation of tissue inhibitor of metalloproteinase 3 (TIMP3) is a prominent feature of SFD/AMD. However, it is not known “how” sub-RPE TIMP3 accumulation promotes SFD/AMD pathology. This is partially because the RPE-CC is a functional composite making it difficult to study the contribution of spatial changes in RPE versus CC layer during disease development in vivo. Furthermore, the lack of a representative model of the RPE-CC in vitro has significantly impacted our ability to study RPE-CC interaction in vitro. Using induced pluripotent stem cells (iPSCs), we have developed an iPSC- RPE-CC model that recapitulate key features of both healthy and AMD/SFD eyes. Specifically, iPSC-RPE-CC shows evidence of fenestrated CC-like vasculature and Bruch’s membrane like ECM. Similarly, SFD iPSC-RPE- CC displays two central hallmarks of SFD/AMD, drusen and choroidal neovascularization (CNV)-like pathology. Notably, longitudinal analyses of control versus SFD iPSC-model showed that sub-RPE TIMP3 accumulation occurs relatively early and precedes maculopathy cellular events. Furthermore, our preliminary proof of concept studies shows that sub-RPE TIMP3 accumulation in the SFD iPSC model promotes pro-maculopathy cellular changes via dysregulated lipid metabolism and sterile inflammation. Based on these strong preliminary studies, the overall goal of this proposal is to establish the independent contribution of sub-RPE TIMP3 accumulation to AMD/SFD pathology development. We will perform spatial (RPE versus CC) and temporal (e.g., prior and after drusen formation) manipulation of TIMP3 expression/activity in i) SFD iPSC-RPE-CC and ii) control iPSC-RPE- CC cultures (iPSCs derived from healthy subjects with normal vision) to test the hypotheses that sub-RPE TIMP3 accumulation leads to dysregulated lipid metabolism and sterile inflammation and consequently i) drusen beneath the RPE monolayer and ii) CC atrophy and CNV. From a therapeutic standpoint, we will pharmacologically target dysregulated lipid metabolism and sterile inflammation in SFD/AMD iPSC models.