Innate Immunomodulation of Retinal Vascular Development

项目摘要 视网膜血管形成是一个高度调节的过程，需要多细胞串扰， 交互.由于视网膜血管发育的复杂性，存在几个关键的知识空白 需要解决的问题例如，调节视网膜血管发育的关键神经胶质细胞类型是 星形胶质细胞，为血管形成奠定了模板。内皮细胞在空间上迁移 有组织的星形胶质细胞模板，形成浅表血管，产生三个相互连接的血管 在成熟的视网膜中。星形胶质细胞发育过程中星形胶质细胞模板的破坏或丧失 与成年期血管的联系可能对血管生长、完整性和功能有害。的 调节星形胶质细胞空间模式的潜在细胞和分子信号传导机制， 在发育过程中随后有组织血管形成仍然不完全清楚。阐明 控制血管发育和功能的分子机制是必要的，以确定更多 致盲视网膜血管病变的有针对性的治疗策略，并确定哪些关键 在某些情况下，不应针对发育过程，例如早产儿视网膜病。我们 主要目标是描述调节星形胶质细胞模板空间排列的信号机制， 血管网形成。 我们的初步研究结果有力地支持了本研究的基本原理。我们的RNA-seq数据显示， 特异性趋化因子和补体基因表达水平在视网膜血管发育期间升高。 有趣的是，一种受影响的趋化因子受体的缺失破坏了星形胶质细胞模板的形成， 小胶质细胞的募集和分布。另一方面，补体成分的缺失导致免疫缺陷。 异常致密的星形胶质细胞模板和畸形的过度尖端细胞形成。根据这些小说 研究结果，我们假设小胶质细胞趋化因子信号传导和补体激活对于正常的 视网膜血管发育我们将在以下两个具体目标中反驳或验证我们的假设： 1：确定趋化因子信号是否招募小胶质细胞来调节星形胶质细胞模板组装。目标2： 定义补体受体在星形胶质细胞模板和血管网络形成中的作用。我们将利用 创新的基于多重RNA/蛋白质的测定、新的离体迁移测定、独特的报告小鼠，以及 cre/lox动物进行细胞特异性缺失。我们预期，拟议研究的成功完成， 确定先天免疫系统在调节高度复杂的视网膜血管发育中的新作用 流程.进一步阐明血管发育的生理调控机制， 还确定了未来视网膜血管病变的假定治疗策略。

Project Summary Retinal blood vessel formation is a highly regulated process that requires multi-cellular crosstalk and interactions. Due to the complexity of retinal vascular development, there are several critical knowledge gaps that need to be addressed. For example, the key glial cell type that regulate retinal vascular development are astrocytes, which lay a template for blood vessel formation. Endothelial cells migrate over the spatially organized astrocytic template to form superficial blood vessels that give rise to three interconnected vascular layers in the mature retina. Disruption of the astrocytic template during development or loss of astrocyte association with blood vessels in adulthood can be detrimental to vascular growth, integrity, and function. The underlying cellular and molecular signaling mechanisms that regulate astrocyte spatial patterning and subsequent organized blood vessel formation during development remain incompletely understood. Elucidating the molecular mechanisms that govern blood vessel development and function is necessary to identify more targeted therapeutic strategies for blinding retinal vascular pathologies, and to identify which critical developmental processes should not be targeted in some contexts, for example retinopathy of prematurity. Our major goal is to delineate the signaling mechanisms that regulate astrocyte template spatial arrangement and vascular network formation. Our preliminary findings strongly support the rationale for the present study. Our RNA-seq data reveal that specific chemokine and complement gene expression levels are elevated during retinal vascular development. Intriguingly, deletion of one of the affected chemokine receptors disrupts astrocyte template formation and microglial recruitment and distribution. On the other hand, deletion of complement components results in an aberrantly dense astrocytic template and dysmorphic excessive tip cell formation. Based on these novel findings, we hypothesize that microglial chemokine signaling and complement activation are critical for normal retinal vascular development. We will refute or validate our hypothesis in the following two Specific Aims: Aim 1: To determine if chemokine signaling recruits microglia to modulate astrocyte template assembly. Aim 2: To define the role of complement receptors in astrocyte template and vascular network formation. We will utilize innovative multiplex RNA/protein based assays, novel ex vivo migration assays, unique reporter mice, and cre/lox animals for cell-specific deletion. We expect that successful completion of the proposed studies will identify novel roles for the innate immune system in regulating highly complex retinal vascular developmental processes. Moreover, further elucidating physiological regulatory mechanisms of vascular development, will also identify future putative therapeutic strategies for retinal vascular pathologies.