Engineering an Atherosclerosis-Resistant Endothelium

描述(申请人提供)：动脉粥样硬化发生在血流模式偏离正常层流模式的血管区域。致动脉粥样硬化的血流动力激活血管内皮细胞募集单核细胞，降低屏障功能，在存在全身危险因素的情况下导致动脉粥样硬化。最近的数据表明，内皮下细胞外基质的组成在这一过程中起着重要的作用。流体流动激活内皮细胞中的核因子-KB、PAK和JNK！细胞依赖纤维连接蛋白(FN)或纤维蛋白原，而不是基底膜蛋白，这是由于结合这些细胞外基质蛋白的整合素发出的不同信号。此外，FN在体内动脉粥样硬化易发部位的发现先于其他疾病指征，提示FN的沉积可能在体内动脉粥样硬化的启动中起作用。我们的体外研究表明，FN基质可以被修饰以抑制NF-KB和JNK，这可能是一种预防或治疗动脉粥样硬化的方法。该项目将由弗吉尼亚大学的一个研究团队执行，研究人员包括：从事机械转导和整合素信号转导的马丁·施瓦茨博士；从事机械转导和图像分析工作的生物工程师布莱恩·赫尔姆克；内皮生物学以及血流模式测量和建模方面的生物工程专家布雷特·布莱克曼；以及心脏病专家、动脉粥样硬化和免疫组织化学动物模型专家伊恩·萨雷姆博克。为了利用上述发现创造的机会，我们将使用血管系统中易发生动脉粥样硬化的部位的流动和应变模式来研究体外致动脉粥样硬化力量的影响。这些曲线将被用来阐明导致动脉粥样硬化易发区域动脉粥样硬化通路持续激活的信号机制。这些信息将被用来设计不激活这些通路的转基因内皮细胞系。为了测试体内结果的相关性，将构建在内皮细胞中表达类似结构的转基因小鼠，并将其与载脂蛋白E“‘”小鼠杂交，以评估它们抑制动脉粥样硬化的能力。总之，这些研究将提供对动脉粥样硬化形成机制的洞察，并测试治疗的新治疗策略。

DESCRIPTION (provided by applicant): Atherosclerosis occurs at regions of the vasculature where flow patterns depart from the normal laminar mode. Atherogenic hemodynamic forces activate the endothelium to recruit monocytes and decrease barrier unction, which in the presence of systemic risk factors leads to atherosclerosis. Recent data show that the composition of the subendothelial extracellular matrix plays an important role in this process. Fluid flow activates NF-KB, PAK and JNK in endothelia! cells on fibronectin (FN) or fibrinogen but not on basement membrane proteins due to differential signaling by the integrins that bind these extracellular matrix proteins. Furthermore, FN is found at atherosclerosis-prone sites in vivo prior to other indications of disease, suggesting that deposition of FN may contribute to initiation of atherosclerosis in vivo. Our in vitro studies have shown that FN matrix can be modified to suppress NF-KB and JNK, suggesting a possible method to Drevent or treat atherosclerosis. The project will be performed by a team of researchers at the University of Virginia consisting of Drs. Martin Schwartz, who works on mechanotransduction and integrin signaling; Brian Helmke, a bioengineer who works on mechanotransduction and image analysis; Brett Blackman, a bioengineer expert in endothelial biology and measuring and modeling flow patterns; and Ian Sarembock, a cardiologist and expert in animal models of atherosclerosis and immunohistochemistry. To take advantage of the opportunity created by the above findings, we will use flow and strain patterns from an atherosclerosis- prone site in the vasculature to study effects of atherogenic forces in vitro. These profiles will be used to elucidate mechanisms of signaling that give rise to sustained activation of atherogenic pathways in athero- prone regions. This information will be used to engineer transfected endothelial cell lines that do not activate these pathways. To test the relevance of the results in in vivo, transgenic mice expressing similar constructs in the endothelium will be constructed and crossed with apolipoproteinE"'" mice to evaluate their ability to suppress atherosclerosis. Together, these studies will provide insight into mechanisms of atherogenesis and test novel therapeutic strategies for treatment.