The role of the Wnt5a/ROR2 in the pathogenesis of pulmonary arterial hypertension.

肺动脉高压（PAH）是一种危及生命的疾病， 肺微血管的进行性损失和再生受损导致的肺压力。 功能性血管网络形成的一个关键事件是周细胞覆盖血管管，高度 专门的壁细胞直接与内皮细胞相互作用，为新生血管提供支持和保护。 形成血管。许多研究试图阐明小血管损失背后的机制 肺微血管内皮细胞（PMVEC）的作用，但很少有研究， 迄今为止，已经探索了周细胞对疾病的贡献。使用一种新的基于磁珠的方法 为了直接从人肺中分离周细胞，我们发现，与从健康肺中分离的周细胞相比， 在个体中，PAH周细胞在血管网络期间不能迁移并与健康的PMVEC结合 阵周细胞向血管募集的机制与细胞因子的激活有关。 Wnt/平面细胞极性（PCP），一种参与组织过程中协调细胞运动和排列的途径， 阵我们的初步研究表明，PMVEC和周细胞表现出共存性， Wnt 5a和ROR 2在共培养中的上调，这表明Wnt/PCP配体-受体对对于 肺血管生成过程中内皮-周细胞相互作用的建立。我们建议（1） Wnt/PCP的激活对于PMVEC和周细胞组织成功能性肺组织是必需的。 微血管和（2）减少Wnt/PCP活性的突变损害肺血管再生后， 损伤我们将使用一种新的内皮特异性Wnt 5a基因敲除小鼠模型， 血管生成测定和基因编辑技术，以研究Wnt 5a和ROR 2在血管生成中的参与。 正常肺血管生成过程中内皮细胞-周细胞相互作用建立和证实形成 这两个基因的失调首次降低了PAH周细胞建立 适当的内皮-周细胞相互作用。我们的最终目标是扩大生物学的知识 参与肺血管生成的反应，并有助于目前开发新的治疗方法 旨在预防和/或逆转PAH中小血管损失的策略。

Pulmonary arterial hypertension (PAH) is a life-threatening disorder that is associated with abnormal increase in pulmonary pressures resulting from progressive loss and impaired regeneration of pulmonary microvessels. A key event in the formation of functional vascular networks is coating of vascular tubes with pericytes, highly specialized mural cells that directly interact with endothelial cells to provide support and protection to newly formed blood vessels. Many studies have attempted to elucidate the mechanisms behind the small vessel loss in PAH by centering on the role of the pulmonary microvascular endothelial cells (PMVECs) but few studies to date have explored the contribution of pericytes to the disease. Using a novel magnetic bead-based method to isolate pericytes directly from human lungs we have found that, compared to pericytes isolated from healthy individuals, PAH pericytes fail to migrate and associate with healthy PMVECs during vascular network formation. The mechanism involved in the recruitment of pericytes to blood vessels is related to activation of the Wnt/Planar cell polarity (PCP), a pathway involved in orchestrating cell motility and alignment during tissue formation. Our preliminary studies have shown that PMVECs and pericytes demonstrate concomitant upregulation of Wnt5a and ROR2 in co-culture arguing that this Wnt/PCP ligand-receptor pair is necessary for establishment of endothelial-pericyte interactions during pulmonary angiogenesis. We propose that (1) activation of Wnt/PCP is necessary for PMVECs and pericytes to organize into functional pulmonary microvessels and (2) that mutations that reduce Wnt/PCP activity impair pulmonary vascular regeneration after injury. We will use a novel mouse model of endothelial-specific Wnt5a knockout together with cell-based angiogenesis assays and gene editing techniques to study the involvement of Wnt5a and ROR2 in the establishment of endothelial-pericyte interaction during normal pulmonary angiogenesis and demonstrate for the first time that dysregulation of these two genes can reduce the capacity of PAH pericytes to establish proper endothelial-pericyte interactions. Our ultimate goal is to expand the knowledge of the biological responses involved in pulmonary angiogenesis and contribute to current efforts to develop new treatment strategies aimed at preventing and/or reversing small vessel loss in PAH.