HUMAN DERMAL ENDOTHELIAL CELLS IN SKIN DISEASE

在前一个赠款周期中，我们负责确定是否 来自皮肤的微血管细胞具有独特的特征， 功能和功能属性，这些功能属性将提供对 内皮细胞在皮肤动态平衡和病理学中的作用。我们 理由是由于病理和实际上大多数生理事件需要 在微血管水平上，来自这个来源的细胞 将是最适合研究特定器官的 响应性。这种方法所固有的是我们的假设，即并非所有 内皮细胞是相似的，从研究中获得的信息 大血管内皮细胞不一定适用于 微血管内皮细胞。当时，甚至现在，几乎所有的 从事大血管内皮细胞研究的实验室 来源于人脐静脉的内皮细胞，因为 分离和培养这些细胞相对容易。相反， 微血管细胞相对较难分离和繁殖， 他们的文化要求非常昂贵。我们已经明确地决定 来自皮肤的微血管内皮细胞与 HUVEC以各种方式，包括增长要求、 细胞分化、细胞黏附分子表达、细胞调控 在生化和分子水平上的黏附分子，以及功能 细胞黏附分子与细胞-细胞和细胞-基质的关系 互动。在下一个赠款周期中，我们选择在 更详细地说，我们所做的三个重要观察结果是 具有重要的生物学意义，显然是微血管所特有的 内皮细胞。这些观察涉及微血管特异的 血管细胞黏附分子1(VCAM1)的调控表达 黏附分子主要参与白细胞的运输和 免疫和炎症反应的定位；CD36，细胞表面 糖蛋白在病理性血管闭塞过程中的关键作用 在微血管系统内；以及肿瘤坏死因子-α和白介素1，两种重要的促进剂。 炎性细胞因子参与血管内皮细胞瘤的发生和定位 皮肤发炎和缺氧性损伤。我们的研究表明， 这些重要蛋白的诱导和表达谱是独特的 在HDMEC中是不同的，这些差异在 局部炎症过程和血管闭塞的发病机制 发生在微血管床内的事件。因此，具体的 本项目的目标是：L)在分子上刻画， VCAM-1对高密度脂蛋白内皮细胞的调节作用 描述生化、结合和分子调控 HDMEC CD36的特性，并将这些特性与 CD36在其他组织中的表达；以及3)确定 肿瘤坏死因子-α、白介素1-α和白介素1β的作用条件和机制 由HDMEC合成并发布。

During the previous grant cycle we undertook the determination of whether microvascular cells from skin possessed unique characteristics, capabilities, and functional properties that would provide insights into the role of endothelial cells in cutaneous homeostasis and pathology. We reasoned that since pathologic and indeed most physiologic events take place at the level of the microvasculature, cells derived from this source would be the most appropriate to study regarding organ specific responsiveness. Inherent in this approach was our hypothesis that not all endothelial cells are alike and that the information derived from studies of large vessel endothelial cells would not be necessarily applicable to microvascular endothelial cells. At that time, and even now, almost all laboratories engaged in the study of endothelial cells used large vessel endothelial cells derived from human umbilical veins, because of the relative ease of isolating and culturing these cells. Conversely, microvascular cells are relatively difficult to isolate and propagate, and their culture requirements are very expensive. We have clearly determined that microvascular endothelial cells from skin differ profoundly from HUVEC in a variety of ways, including growth requirements, state of differentiation, expression of cell adhesion molecules, regulation of cell adhesion molecules at the biochemical and molecular levels, and function of cell adhesion molecules as they relate to cell-cell and cell-matrix interactions. In this next grant cycle, we have chosen to pursue in greater detail three important observations that we have made that are biologically significant and apparently unique to microvascular endothelial cells. These observations involve the microvascular-specific regulated expression of vascular cell adhesion molecule-1 (VCAM1), a cell adhesion molecule fundamentally involved in leukocyte trafficking and localization of immune and inflammatory responses; CD36, a cell surface glycoprotein critically involved in pathologic vaso-occlusive processes within the microvasculature; and TNF-alpha and IL-1, two essential pro- inflammatory cytokines implicated in the initiation and localization of cutaneous inflammation and hypoxic damage. Our studies indicate that the induction and expression profiles of these important proteins are uniquely different in HDMEC, and that these differences are critically important in the pathogenesis of localized inflammatory processes and vaso-occlusive events which occur within the microvascular bed. Therefore, the Specific Aims of this project are: l) To characterize at the molecular, biochemical, and functional levels the regulation of VCAM-1 on HDMEC; 2) To delineate the biochemical, binding, and molecular regulatory characteristics of the HDMEC CD36, and compare these characteristics to those of CD36 described in other tissues; and 3) To determine the conditions and mechanisms by which TNF-alpha, IL-1alpha, and IL-1beta are synthesized and released by HDMEC.