GENETICS OF ARTERIAL AND PROGENITOR ENDOTHELIAL CELLS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 传统的风险因素（例如，脂蛋白、炎症、氧化应激）仅解释动脉粥样硬化疾病风险的一半。我们认为动脉壁对循环危险因素的反应占剩余风险的很大比例。动脉壁是血管病变发生的部位，决定了血管疾病的内源性易感性。此外，动员循环内皮祖细胞（CEPC）在血管损伤的反应在动脉粥样硬化的发生和发展中起着重要作用。在这个项目中，我们将首先测试的假设，即遗传变异是内皮细胞对动脉粥样硬化刺激的反应的主要决定因素，因此在很大程度上是动脉粥样硬化易感性的变化负责。使用动脉活检，我们将收集大血管内皮细胞（EC）从405纯种狒狒，并将这些细胞在体外致动脉粥样硬化的挑战。我们将测量内皮功能障碍的标志物，包括eNOS、VCAM-1、ICAM-1、E-Selectin、vWF和MCP-1的mRNA和蛋白水平，以及内皮细胞活化前后的凋亡百分比。其次，我们将测试的假设，即循环CEPC的基础数量是受遗传调控的，动员CEPC的数量在血管损伤的反应也是遗传控制。我们将通过股动脉结扎从450只基础饮食的狒狒和80只7周攻击后的狒狒中收集体内血管损伤之前和之后的血液，并且我们将通过流式细胞术在损伤之前和损伤后72小时定量血液中的CEPC数量，以评估动员的祖细胞的诱导。这些结果将进行全基因组扫描，以确定携带基因的染色体区域 影响内皮功能或CEPC数量。第三，我们将测试的假设，EC功能特性和CEPC数字预测动脉粥样硬化病变的易感性在一项研究中，111狒狒喂养致动脉粥样硬化饮食2年前尸检和评估病变。第四，我们将检验假设， 致动脉粥样硬化饮食阻碍CEPC分化能力，通过对来自120只狒狒的培养CEPC进行功能测定，在2年饮食挑战之前和期间，以及在股动脉活检之前和之后。最终的目标是确定调节动脉粥样硬化危险因素功能反应的基因， 成熟内皮细胞内衬动脉壁和在血液中循环的祖内皮细胞。我们的项目将建立一个非人灵长类动物模型，可用于血管疾病的药理学和介入研究，直接评估动脉壁内皮功能。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Traditional risk factors (e.g., lipoproteins, inflammation, oxidative stress) explain only half the risk of atherosclerotic disease. We believe that the response of the arterial wall to circulating risk factors accounts for a significant proportion of the remaining risk. Arterial wall is where the vascular pathological changes occur, and it determines endogenous susceptibility to vascular diseases. Furthermore, mobilization of circulating endothelial progenitor cells (CEPCs) in response to vascular injury plays a major role in the initiation and progression of atherosclerosis. In this project, we will first test the hypothesis that genetic variation is the major determinant of endothelial responses to atherogenic stimuli and consequently is largely responsible for variation in susceptibility to atherosclerosis. Using arterial biopsies, we will collect macrovascular endothelial cells (ECs) from 405 pedigreed baboons, and will subject these cells to in vitro pro-atherogenic challenges. We will measure markers of endothelial dysfunction including mRNA and protein levels of eNOS, VCAM-1, ICAM-1, E-Selectin, vWF and MCP-1, and percentage of apoptosis before and after endothelial cells are activated. Second, we will test the hypotheses that the basal number of circulating CEPCs is regulated genetically, and that the number of mobilized CEPCs in response to vascular injury is also genetically controlled. We will collect blood prior to and after in vivo vascular injury by femoral artery ligation from 450 baboons on basal diet and 80 after a 7-wk challenge and we will quantify CEPC number in the blood by flow cytometry before and 72 hr post injury to evaluate the induction of mobilized progenitor cells. The results will be subjected to genome wide scans to identify chromosomal regions that harbor genes affecting endothelial function, or number of CEPCs. Third, we will test the hypothesis that EC functional properties and CEPC numbers predict susceptibility to atherosclerotic lesions in a study of 111 baboons fed atherogenic diet for 2 yr prior to necropsy and assessment of lesions. Fourth, we will test the hypothesis that an atherogenic diet hampers CEPC differentiation capacity by conducting functional assays on cultured CEPCs from 120 baboons before and during a 2-yr dietary challenge, and before and after femoral artery biopsy. The ultimate goal is to identify genes that regulate functional responses to atherogenic risk factors in mature endothelial cells lining arterial wall and in progenitor endothelial cells circulating in the blood. Our project will establish a nonhuman primate model that can be used for pharmacological and interventional investigations of vascular diseases with direct assessment of arterial wall endothelial function.