Elucidating the role of pericytes in angiogenesis in the brain using a tissue-engineered microvessel model

项目摘要 血管生成是一个复杂和严格调控的过程，对于组织修复是必不可少的，以应对损伤或 疾病。在成年人的大脑中，脑血管系统基本上处于静止状态，但与血管生成有关 疾病(例如中风、神经退行性疾病和脑癌)、伤口愈合(例如创伤性脑 以及生理因素(如运动、高原适应等)。在普遍接受的模型中 在脑血管生成方面，当血管受到血管生成信号的影响时，周细胞从激活中分离出来 内皮细胞，在萌芽形成和生长过程中是被动的旁观者，只迁移回周围 成熟期新生内皮细胞。然而，在人类和动物模型中进行的一些研究 有报道称，周细胞可以在血管生成中发挥积极作用，引导萌芽生长，促进 茎细胞的迁移。 该项目的目标是确定周细胞在脑血管生成中的作用。我们的专业 假设周细胞可以被选择性地激活，成为TIP细胞，并引导血管生成的生长 芽菜。这一目标将分三个目标来实现。在目标1中，我们将使用组织工程化后毛细血管 小静脉模型评估低氧和生长因子梯度在周细胞引导的血管生成中的作用。在AIM 2、我们将评估周细胞在血管生成过程中的转录图谱。免疫组织化学和原位RNA 杂交将用于检查TIP细胞的关键标记以及验证关键测序结果。在……里面 目的3，我们将进行概念验证实验，以验证基因编辑可用于 工程师TIP细胞表型。了解周细胞在成人脑血管生成中的作用 了解脑血管系统对各种扰动的反应，将使 脑血管修复新疗法的发展。

Project Summary Angiogenesis is a complex and tightly regulated process essential for tissue repair in response to injury or disease. In the adult human brain, the cerebrovasculature is largely quiescent but angiogenesis is associated with disease (e.g. stroke, neurodegenerative disease, and brain cancer), wound healing (e.g. traumatic brain injury), and physiological factors (e.g. exercise, high altitude adaptation, etc.). In the generally accepted model of brain angiogenesis, when blood vessels are exposed to angiogenic cues, pericytes detach from activated endothelial cells and are passive bystanders during sprout formation and growth, only migrating back to surround the newly formed endothelium in the maturation phase. However, a few studies in humans and animal models have reported that pericytes can play an active role in angiogenesis, leading sprout growth and promoting the migration of stalk cells. The objective of this project is to identify the role of pericytes during angiogenesis in the brain. Our major hypothesis is that pericytes can be selectively activated to become the tip cells and lead the growth of angiogenic sprouts. The objective will be addressed in three aims. In Aim 1, we will use a tissue-engineered post-capillary venule model to assess the role of hypoxia and growth factor gradients on pericyte-guided angiogenesis. In Aim 2, we will evaluate the transcriptomic profile of pericytes during angiogenesis. Immunostaining and in situ RNA hybridization will be used to examine key markers of tip cells as well as to validate key sequencing results. In Aim 3, we will perform a proof-of-concept experiment to test the hypothesis that gene editing can be used to engineer tip cell phenotype. Understanding the role of pericytes in adult brain angiogenesis is important in understanding the response to the cerebrovasculature to a wide range of perturbations and will enable the development of new therapies for cerebrovascular repair.