Lung endothelial cell phenotypes

项目摘要 内皮细胞排列在血管上并连接所有器官系统。然而，内皮细胞表现出丰富的 结构和功能的多样性。这种异质性在不同组织中的内皮细胞之间是明显的。 在器官内，在内皮细胞中，沿着器官内的单个血管段沿着，以及在器官之间， 相邻的细胞这个项目的资助是建立在这样一个总体假设上的： 肺动脉、毛细血管和静脉在表型上是不同的，其中每种细胞类型都是特化的 以满足其血管生态位的独特需求。这些细胞之间的特化是由离散的 第二信使信号网络的组织。因此，在这场竞争性的更新中，我们的每一个人， 研究内皮细胞信号网络的组织和功能。我们评估了 第二信使信号，这些信号如何在细胞内传播，是什么限制了细胞的寿命， 信号，以及哪些效应蛋白主要由信号激活。我们第一次可以测量 随着时间的推移，第二信使在现实的细胞几何形状中的三维传播。细菌如 铜绿假单胞菌在感染过程中损害内皮细胞功能， 急性肺损伤铜绿假单胞菌改变了第二信使信号的组织和功能， 在某些情况下，细菌利用在宿主- 病原体相互作用铜绿假单胞菌及其胞外酶破坏了内皮细胞屏障，因此，我们 项目使用这种细菌及其毒素来探测内皮异质性和功能的决定因素， 包括屏障完整性。所有项目都利用了纵向一体化的方法，从使用 将培养的细胞（例如，具有对基底硬度的控制）与各种原位（例如，分离的器官，肺切片， 分离的血管和无细胞肺支架）和体内制备物。在每一种情况下，注意力 是支付给什么是相似的，什么是不同的，关于各自的细胞表型。总的来说， 系统地提出了三个具体目标：（1）识别和测试新的分子机制 (e.g.特征），其负责位点特异性内皮细胞功能，特别是在微循环中， (2)确定这些机制在疾病的临床前模型中的重要性，以及（3）将新的 临床前疾病模型的治疗方法。项目具有高度互动性。界定机制 第二信使信号网络的基础不仅可以告诉我们内皮细胞的性质， 异质性，但提供了前所未有的深入了解宿主-病原体相互作用，破坏内皮细胞 细胞屏障并引起组织水肿。对内皮细胞信号转导网络的机制性洞察将 揭示了改善内皮功能障碍的新的治疗方法。

PROJECT SUMMARY Endothelium lines blood vessels and interconnects all organ systems. However, endothelial cells exhibit a rich diversity in structure and function. Such heterogeneity is apparent between endothelial cells in different organs, in endothelial cells along a single vascular segment within an organ, and between immediately adjacent cells. This program project grant is founded on the overall hypothesis that endothelium lining pulmonary arteries, capillaries, and veins is phenotypically distinct, where each cell type is specialized to fulfill the unique demands of its vascular niche. Specialization among these cells is encoded by discrete organization of second messenger signaling networks. Therefore, in this competitive renewal each of our projects examines the organization and function of endothelial cell signaling networks. We evaluate the origin of second messenger signals, how these signals spread inside of the cell, what limits the lifespan of the signals, and which effector proteins are principally activated by the signals. For the first time we can measure three-dimensional spread of second messengers in realistic cellular geometries over time. Bacteria such as Pseudomonas aeruginosa impair endothelial cell function during the course of infection that culminates in acute lung injury. P. aeruginosa alters the organization and function of second messenger signaling, and in some instances, the bacterium utilizes enzymes that generate second messenger signals during the host- pathogen interaction. P. aeruginosa and its exoenzymes disrupt the endothelial cell barrier, and hence, our projects use this bacterium and its toxins to probe determinants of endothelial heterogeneity and function, including barrier integrity. All projects take advantage of vertically integrated approaches, ranging from the use of cultured cells (e.g. with control for substrate stiffness) to various in situ (e.g. isolated organs, lung slices, isolated blood vessels, and cell-free lung scaffolds) and in vivo preparations. In each of these cases, attention is paid to what is similar, and what is dissimilar, about the respective cell phenotypes. Altogether, projects systematically address three specific aims or objectives, to: (1) identify and test novel molecular mechanisms (e.g. signatures) that are responsible for site-specific endothelial cell function, especially in the microcirculation, (2) determine the importance of these mechanisms in preclinical models of disease, and (3) translate novel therapeutic approaches to preclinical models of disease. Projects are highly interactive. Defining mechanisms that underlie second messenger signaling networks will not only inform us as to the nature of endothelial cell heterogeneity, but provide unprecedented insight into host-pathogen interactions that disrupt the endothelial cell barrier and cause tissue edema. Mechanistic insight into endothelial signal transduction networks will reveal novel therapeutic approaches to improve endothelial dysfunction.