Vessel Shear Stress & Cytomegalovirus Disease: Molecular Basis of Atherosclerosis

描述(申请人提供)：心脏病和中风是发达国家导致死亡和长期残疾的主要原因。动脉粥样硬化是心血管疾病的主要病因，被广泛认为是一种由内皮细胞损伤或功能障碍引起的炎症性疾病。人类巨细胞病毒(HCMV)是一种广泛传播的人类病原体，长期以来一直被认为是心血管疾病的危险因素。动脉粥样硬化的发病机制涉及多种细胞类型之间的相互作用，通常发生在大中型动脉的分支或弯曲区域，这些动脉暴露于血流模式紊乱和低流体剪应力。到目前为止，人类巨细胞病毒感染在动脉粥样硬化中的作用仅在静态条件下进行了探索。鉴于细胞间相互作用的重要性和血流在动脉粥样硬化形成中的作用，本研究计划的主要目标是利用流动模型系统在生理背景下揭示HCMV诱导动脉粥样硬化的关键机制。我们计划探索在均匀和湍流的高或低剪应力条件下，人巨细胞病毒与内皮细胞的双向相互作用。为了做到这一点，我们将在室内培养内皮细胞，以允许介质在模拟血流的细胞上调节流动。均匀流室和阶梯流室的使用将使我们能够模拟不同类型的流动模式和发生在血管系统不同部分的剪应力。利用这些系统，我们计划分析暴露在不同流动模式和剪切力下的内皮细胞中HCMV感染的影响，因为它与病毒进展和动脉粥样硬化前基因在蛋白质和RNA水平上的表达有关。此外，我们计划确定在血流的背景下，内皮细胞感染HCMV最终如何调节外周血白细胞的黏附和跨内皮细胞迁移，这是动脉粥样硬化病变发展的主要初始步骤。作为一个整体，本研究计划从血流的生理角度探讨HCMV、内皮细胞和白细胞之间的相互作用，以阐明HCMV诱导动脉粥样硬化的机制。鉴于人巨细胞病毒在人群中的流行(60%-80%的成人)、与动脉粥样硬化相关的死亡率及其对医疗费用的影响，迫切需要在人体动脉发生的生理条件下确定巨细胞病毒感染在动脉粥样硬化形成过程中的作用。这项研究计划的长期目标是为动脉粥样硬化的病毒发病机制提供新的见解，从而为预防与HCMV感染相关的内皮细胞损伤提供经济有效的新策略。 公共卫生相关性：动脉粥样硬化是心血管疾病的主要原因(发达国家死亡的主要原因)，其对保健费用的影响是巨大的。血流动力学因素是动脉粥样硬化的主要调节因素，人类巨细胞病毒(HCMV)感染被认为是疾病进展的重要因素。该项目采用了新的方法来研究动态流动环境中HCMV感染对血管功能的影响，结果将填补目前我们对生理或病理环境中病毒与血管细胞之间双向相互作用的了解空白，从而有助于发现新的治疗方法。

DESCRIPTION (provided by applicant): Heart disease and stroke are the principal causes of mortality and long-term disability in developed nations. The major underlying cause of cardiovascular diseases is atherosclerosis, which is widely recognized as an inflammatory disease initiated by endothelial cell injury or dysfunction. Human cytomegalovirus (HCMV), a widely disseminated human pathogen, has long been proposed as a risk factor for cardiovascular disease. The pathogenesis of atherosclerosis involves interactions between multiple cell types and typically occurs in large to medium-sized arteries in regions that are branched or curved, which are exposed to disturbed patterns of blood flow and low fluid shear stress. To date, the role of HCMV infection in atherosclerosis has only been explored in static conditions. Given the importance cell-cell interactions and the role of blood flow in atherogenesis, the major goal of this research plan is to uncover key mechanisms in HCMV induced atherosclerosis in a physiological context using a flow model system. We plan to explore the bi-directional interactions of HCMV and endothelial cells under conditions of high or low shear stress in uniform and turbulent flow. To do this we will culture endothelial cells in chambers that will allow for the regulated flow of media over cells simulating blood flow. The use of uniform and step-flow chambers will allow us to simulate different types of flow patterns and shear stresses that occur in different parts of the vasculature. Using these systems we plan to analyze the effects of HCMV infection in endothelial cells exposed to varying flow patterns and shear stress as it relates to viral progression and proatherosclerotic gene expression at the protein and RNA level. In addition, we plan to determine how HCMV infection of endothelial cells in the context of flow ultimately modulates the adhesion and transendothelial migration of peripheral blood leukocytes, which is the major initial step in the development of atherosclerotic lesions. As a whole, this research plan is intended to explore the interactions between HCMV, endothelial cells, and leukocytes in the physiological context of blood flow in order to elucidate the mechanisms of HCMV induced atherosclerosis. Given the prevalence of HCMV in the human population (60-80% of adults), the mortality associated with atherosclerosis, and its impact on healthcare costs, there is a great need to determine the role of HCMV infection in the progression of atherogenesis in the physiological conditions that occur in the human artery. The long-term goal of this research plan is to provide novel insights into viral pathogenesis of atherosclerosis leading to cost effective new strategies for prevention of endothelial cell damage associated with HCMV infection. PUBLIC HEALTH RELEVANCE: Atherosclerosis is the major cause cardiovascular diseases (the leading cause of mortality in developed countries) and its impact on health care costs is enormous. Hemodynamic factors are major regulators of atherosclerosis, and human cytomegalovirus (HCMV) infection has been proposed as an important factor in disease progression. The proposed project employs novel approaches to study the effects of HCMV infection on vascular functions in a dynamic flow environment, and the results will fill the current gap in our understanding of bi-directional interactions between virus and vascular cells in physiological or pathological environments, thus facilitating the discovery of new therapies.