Extracellular vesicles from endothelial colony forming cells as paracrine mediators of neurovasculotrophic repair of the retina

项目概要/摘要： 目前缺血性视网膜病的治疗被设计为在晚期抑制血管渗漏和增殖。 疾病，但不靶向缺血和/或炎症驱动的病理性新血管形成。一 有希望的替代方法是刺激功能性、生理性血管生长和稳定性。一 称为内皮集落形成细胞（ECFC）的内皮祖细胞亚群可以促进这一点。在 缺血性视网膜病变（氧诱导的视网膜病变，OIR）的小鼠模型中，ECFC提供了显著的 血管和神经营养拯救作用。一些证据，包括我们实验室发表的发现， 证明这种治疗效果是通过旁分泌作用介导的。然而，这其中的细节 机制仍不确定。 最近发现，从ECFC脱落的含有microRNA的细胞外囊泡（EV） OIR模型中的拯救效应。ECFC衍生的EV促进内皮细胞迁移并增加内皮细胞的增殖。 血管生成相关基因的表达。弗里德兰德实验室已经证明， 其特征在于表面标志物CD 44（CD 44 hi）的高表达，表现出更稳健的血管-和 在OIR模型中，通过旁分泌， 机制根据这些数据，该提案的总体假设是， CD 44 hi ECFC至少部分归因于从其释放的EV中的生物活性微小RNA（miR）货物。 ECFC亚群。我建议研究哪些miR在从CD 44 hi ECFC脱落的EV中上调， 以确定负责ECFC EV的神经血管营养作用的新型miR。电动汽车将 然后进行工程改造，以增加这些候选miR的表达，目的是重新设计治疗方法， 在OIR模型中实现甚至更大的治疗效果。 作为miR的天然载体，EV可能是一种高度有效的药物递送载体，其规避了miR的风险。 与基于细胞的治疗相关的肿瘤发生。ECFC衍生的电动汽车回家的网站 缺血/血管生成，潜在地限制全身递送的任何有害副作用。然而，更大的 了解EV的异质性群体及其货物和功能之间的关系 在转化为临床成为现实之前，必须开发效果。

Project Summary/Abstract: Current treatments for ischemic retinopathies are designed to inhibit vascular leakage and proliferation in late disease, but do not target the ischemia and/or inflammation driving pathological neovascularization. A promising alternative approach is the stimulation of functional, physiologic vascular growth and stability. A subset of endothelial progenitor cells called endothelial colony forming cells (ECFCs) can facilitate this. In mouse models of ischemic retinopathy (oxygen-induced retinopathy, OIR), ECFCs provide a significant vasculo- and neurotrophic rescue effect. Several lines of evidence, including published findings from our lab, demonstrate this therapeutic effect to be mediated via paracrine action. However, the details of this mechanism remain uncharacterized. MicroRNA-containing extracellular vesicles (EVs) shed from ECFCs were recently discovered to recapitulate this rescue effect in the OIR model. ECFC-derived EVs promote endothelial cell migration and increase the expression of angiogenesis-related genes. The Friedlander lab has demonstrated that a subset of ECFCs characterized by high expression of the surface marker CD44 (CD44hi) exhibit a more robust vasculo- and neurotrophic rescue effect than ECFCs with low CD44 expression in the OIR model via a paracrine mechanism. In light of these data, the overarching hypothesis of this proposal is that the superior effect of CD44hi ECFCs is attributable, at least in part, to the bioactive microRNA (miR) cargo in EVs released from this ECFC subpopulation. I propose to investigate which miRs are upregulated in EVs shed from CD44hi ECFCs in order to identify novel miRs responsible for the reported neurovasculotrophic effects of ECFC EVs. EVs will then be engineered to increase expression of these candidate miRs with the goal of re-designing therapies that achieve even greater therapeutic effects in the OIR model. As natural carriers of miRs, EVs may be a highly effective drug delivery vehicle that circumvents the risks of tumorigenesis associated with cell-based therapeutics. ECFC-derived EVs home to sites of ischemia/angiogenesis, potentially limiting any deleterious side effects of systemic delivery. However, a greater understanding of heterogeneous populations of EV and the relationship between their cargo and functional effects must be developed before translation into the clinic can become a reality.