Modeling Von Willebrand Factor Behavior in the Pulmonary Circulation in Health and Disease

项目总结 肺动脉高压(PAH)是一种高度病态的疾病，其病理特征是 动脉和小动脉微血栓形成，血管收缩，内膜和中膜增生。其作用机制 潜在的多环芳烃的启动和进展仍然不完全清楚。探索潜在的小说 PAH的贡献者将有助于了解疾病和开发新的治疗靶点。 有证据表明，血管内皮细胞活化在PAH的发病机制中起重要作用。一个重要的 内皮细胞活化的早期后果是血管内皮细胞释放von Willebrand因子(VWF) 细胞通过胞吐预先形成的细胞器称为韦贝尔-帕莱德小体(WPB)。VWF调节绑定 在内皮和循环血液成分(如血小板)之间，并促进微血管 血栓形成和炎症。VWF在人类疾病中导致血管功能障碍，包括 动脉粥样硬化、静脉血栓形成、脓毒症和血栓性微血管病变。患有PAH的患者有 改变多聚体组成后循环中的VWF水平增加，并显示VWF染色增加 尸检发现在肺内皮细胞内。循环VWF水平与PAH的病情严重程度相关。 在对体循环的研究中，VWF促进微血管血栓形成、平滑肌细胞 血小板的增殖和募集。所有这些过程都参与了PAH，而VWF的分泌可能 因此，促进了PAH的疾病进展。嬴政博士创造了内皮化生物工程 微血管重现微血管系统的结构和流动状况，并允许使用 特定来源的人体组织。本研究方案侧重于应用郑氏实验室的微血管模型 目的：研究VWF在肺循环中的行为。这项提议的项目将描述这种表达 和VWF在肺内皮细胞内的储存，导致VWF释放的环境因素，以及 血管内皮细胞因子释放对肺内皮细胞和肺血管顺应性的影响 肌肉。本研究方案包括三个主要目的：(1)研究VWF的表达、储存和分泌 在不同肺血管起源的细胞中(2)评估PAH中的环境条件如何影响 VWF的表达、储存和释放(3)研究VWF释放增加对血管的影响 改建。这项研究将为未来VWF下游效应的机理研究奠定基础 对肺血管系统的影响，并可能导致VWF靶向疗法的发展 多环芳烃的治疗。由于vwf还与许多系统性血管疾病有关，这项研究可能会 在肺血管生物学以外有广泛的应用。

PROJECT SUMMARY Pulmonary arterial hypertension (PAH) is a highly morbid disease characterized pathologically by pulmonary arterial and arteriolar microthrombosis, vasoconstriction, and intimal and medial hyperplasia. The mechanisms underlying PAH initiation and progression remain incompletely understood. Exploring potential novel contributors to PAH will aid in disease understanding and the development of new therapeutic targets. Evidence suggests that endothelial activation plays a crucial role in the pathogenesis of PAH. An important early consequence of endothelial activation is the release of von Willebrand Factor (VWF) from endothelial cells via exocytosis of pre-formed organelles known as Weibel-Palade bodies (WPB). VWF mediates binding between the endothelium and circulating blood components such as platelets, and promotes microvascular thrombosis and inflammation. VWF contributes to vascular dysfunction in human diseases including atherosclerosis, venous thrombosis, sepsis, and the thrombotic microangiopathies. Patients with PAH have increased levels of circulating VWF with altered multimer composition, and display increased staining for VWF within the pulmonary endothelium on autopsy. Circulating VWF levels correlate with disease severity in PAH. In studies of the systemic circulation, VWF promotes microvascular thrombosis, smooth muscle cell proliferation, and recruitment of platelets. All these processes are involved in PAH, and VWF secretion may therefore contribute to disease progression in PAH. Dr. Ying Zheng has created endothelialized bioengineered microvessels that recapitulate the architecture and flow conditions of the microvasculature and allow use of human tissues of defined origin. This research proposal focuses on applying the Zheng lab microvessel model to study VWF's behavior in the pulmonary circulation. This proposed project will characterize the expression and storage of VWF within the pulmonary endothelium, the environmental factors leading to VWF release, and the downstream effects of VWF release on the pulmonary endothelium and pulmonary vascular smooth muscle. This research proposal comprises three main aims: (1) Study VWF expression, storage, and secretion in cells of different pulmonary vascular origin (2) Evaluate how environmental conditions seen in PAH affect VWF expression, storage, and release (3) Examine the consequences of increased VWF release on vascular remodeling. This research will set the stage for future mechanistic studies on the downstream effects of VWF on the pulmonary vasculature, and may lead to the development of VWF-targeted therapeutics for the treatment of PAH. As VWF is also implicated in numerous systemic vascular diseases, this research is likely to have broad application beyond pulmonary vascular biology.