Assessing the effects of extracellular vesicles on a human in vitro dry AMD model

年龄相关性黄斑变性（AMD）是老年人失明的主要原因，分为干性和湿性黄斑变性两种。除了黄斑的光感锥光感受器缺失外，视网膜色素上皮（RPE）也受到严重影响。虽然抗vegf疗法已在临床上用于湿性AMD，以抑制有害的血管生长，但目前尚无有效的治疗干性AMD的方法。尽管RPE替代疗法在晚期AMD的临床试验中得到了检验，但这种方法的特点是存在与安全性、移植生产和成本相关的挑战。因此，发展替代治疗方法，特别是在疾病早期阶段进行干预，具有很高的临床需求。细胞外囊泡（EVs）是一种无细胞系统，目前被研究用于递送治疗分子和预防几种疾病的病理状况，因此也代表了AMD的潜在治疗选择。ev参与生理和病理细胞间的通讯，它们的产生和分泌是有针对性的，它们可以通过不同的成分激活或抑制靶细胞内的特定信号通路，包括mirna，一类复杂的基因调控RNA分子。事实上，EVs已经在健康和患病的视网膜中被发现，它们在不同的细胞类型之间传递生物信号。在这项研究中，我们的目标是通过以下方法来评估人类RPE衍生的ev对RPE损伤的体外模型的影响：(i)将我们建立的氧化应激模型应用于人类ipsc衍生的RPE细胞作为干性AMD模型，（ii）分离和表征RPE衍生的ev， （iii）评估RPE- ev对应激的人类RPE细胞的拯救潜力，以及（iv）利用RNA谱分析和生物信息学分析鉴定和评估RPE- ev中潜在的治疗成分。并研究鉴定的mirna对应激RPE细胞的影响。这项研究的结果将确定ev和mirna对受损RPE细胞的治疗效果，作为治疗干性AMD的潜在新选择。

Age related macular degeneration (AMD) is the leading cause for blindness in the elderly population and is classified into two forms of dry and wet AMD. Besides the loss of the light-sensing cone photoreceptors in the macula also the underlying retinal pigment epithelium (RPE) is severely affected in AMD pathology. While anti-VEGF therapies have been clinically established for wet AMD to inhibit detrimental vessel growth, no effective treatment is currently available for dry AMD. Though RPE replacement therapies are examined in clinical trials for late stage AMD, such approaches are characterized by challenges related to safety, transplant production, and costs. Thus, the development of alternative therapeutic approaches, particularly interfering at early disease stages, is of high clinical need. Extracellular vesicles (EVs) represent a cell free system that is currently investigated for the delivery of therapeutic molecules and prevention of pathological conditions in several diseases, thus representing a potential therapeutic treatment option also for AMD. EVs are involved in physiological and pathological cell-cell communication, their production and secretion is targeted, and they can activate or inhibit specific signalling pathways inside their target cells via different components including miRNAs, a class of complex gene regulatory RNA molecules. Indeed, EVs have been identified in the healthy and diseased retina, where they transferred biological signals between different cell types. In this study, we aim to assess the effects of human RPE-derived EVs on an in vitro model of RPE damage by (i) adapting our established oxidative stress model to human iPSC-derived RPE cells as a model of dry AMD, (ii) isolating and characterizing RPE-derived EVs, (iii) assessing the rescue potential of RPE-EVs on stressed human RPE cells, and (iv) identifying and evaluating potential therapeutic components within RPE-EVs using RNA profiling and bioinformatics analysis, and investigating the effects of identified miRNAs on stressed RPE cells. The results of this study will determine the therapeutic effect of EVs and miRNAs on damaged RPE cells as potential novel options for the treatment of dry AMD.