Integrin-CCN1 Interaction in Vascular Thrombogenicity

整合素-CCN1 相互作用在血管血栓形成中的作用

• 批准号: 6920899
• 负责人: Stephen CT Lam
• 金额: $ 34.43万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-22 至 2009-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6920899
• 关键词: atherosclerosis; biological signal transduction; cardiovascular disorder epidemiology; cardiovascular disorder risk; cell adhesion; cell migration; cell proliferation; clinical research; gene expression; genetically modified animals; human subject; immediate early protein; integrins; interleukin 1; laboratory mouse; ligands; monocyte; monocyte chemoattractant protein 1; muscle cells; protein protein interaction; site directed mutagenesis; thromboplastin; thrombosis; vascular smooth muscle

DESCRIPTION (provided by applicant): CCN1 (CYR61), a novel integrin ligand of the CCN family of matricellular regulatory proteins, supports cell adhesion, promotes cell migration and enhances growth factor-induced cell proliferation. Whereas CCN1 is present at low levels in healthy adult blood vessels, its expression is upregulated in vascular diseases such as atherosclerosis and proliferative restenosis. Transmigrated monocytes and vascular smooth muscle cells (VSMCs) play important roles in vascular disease development. Recently, we showed that monocytes and VSMCs adhere to CCN1 through integrin alpha-M-beta-2 and alpha-6-beta1, respectively. Moreover, CCN1 induces gene expression in monocytes, resulting in upregulation of interleukin 1-beta (IL-1-beta), monocyte chemotactic protein-1 (MCP-1), and tissue factor. Based on these observations, we hypothesize that: CCN1 expression in the vessel wall modulates monocyte and VSMC function, leading to an increased risk of atherosclerosis and thrombosis. In this proposal, we aim: 1) To characterize CCN1 interaction with integrins alpha-M-beta-2 and alpha-6-beta-1. We have identified the H2 and T1 sequences in CCN1 as novel binding sites for alpha-M-beta-2 and alpha-6-beta-1 respectively. By mutagenesis, we will define critical residues in these sequences mediating integrin interaction and create CCN1 mutants defective in alpha-M-beta-2 or alpha-6-beta-1 binding. 2) To examine the ability of CCN1 to induce monocyte transmigration. We will also characterize CCN1-induced gene expression in monocytes focusing on IL-1-beta, MCP-1 and tissue factor. The signaling pathways involved in this process will be investigated. 3) To evaluate the ability of CCN1 to stimulate VSMC phenotype change and proliferation. CCN1-induced expression of tissue factor and its inhibitor in VSMCs will also be examined. 4) To determine the in vivo effect of CCN1 expression on vascular disease development. We will generate transgenic mice in which doxycycline regulates inducible expression of CCN1 in arterial SMCs. We will examine whether CCN1 expression in vessel walls induces monocyte transmigration, VSMC proliferation, and tissue factor expression. Using this transgenic mouse model, will examine whether CCN1 expression in vessel walls accelerates diet-induced atherosclerosis and the formation of occluding thrombi in a photochemically induced vascular injury model. These studies will provide new insights into the mechanistic basis of the development of vascular diseases.

描述（由申请人提供）：CCN 1（CYR 61）是一种基质细胞调节蛋白CCN家族的新型整联蛋白配体，支持细胞粘附、促进细胞迁移并增强生长因子诱导的细胞增殖。尽管CCN 1在健康成人血管中以低水平存在，但其表达在血管疾病如动脉粥样硬化和增殖性再狭窄中上调。跨膜单核细胞和血管平滑肌细胞（VSMCs）在血管疾病的发生发展中起重要作用。最近，我们发现单核细胞和VSMC分别通过整合素α-M-β-2和α-6-β 1粘附于CCN 1。此外，CCN 1诱导单核细胞中的基因表达，导致白细胞介素1-β（IL-1-β）、单核细胞趋化蛋白-1（MCP-1）和组织因子的上调。基于这些观察，我们假设：CCN 1在血管壁中的表达调节单核细胞和VSMC功能，导致动脉粥样硬化和血栓形成的风险增加。在本提案中，我们的目标是：1）表征CCN 1与整合素α-M-β-2和α-6-β-1的相互作用。我们已经鉴定了CCN 1中的H2和T1序列分别作为α-M-β-2和α-6-β-1的新结合位点。通过诱变，我们将确定这些序列中介导整联蛋白相互作用的关键残基，并产生α-M-β-2或α-6-β-1结合缺陷的CCN 1突变体。2)检测CCN 1诱导单核细胞迁移的能力。我们还将表征CCN 1诱导的单核细胞中的基因表达，重点是IL-1-β、MCP-1和组织因子。参与这一过程的信号通路将被调查。3)评价CCN 1刺激VSMC表型改变和增殖的能力。还将检查CCN 1诱导的VSMC中组织因子及其抑制剂的表达。4)确定CCN 1表达对血管疾病发展的体内作用。我们将产生转基因小鼠，其中多西环素调节动脉SMC中CCN 1的诱导型表达。我们将研究CCN 1在血管壁中的表达是否诱导单核细胞迁移、VSMC增殖和组织因子表达。使用这种转基因小鼠模型，将检查血管壁中的CCN 1表达是否加速饮食诱导的动脉粥样硬化和光化学诱导的血管损伤模型中闭塞血栓的形成。这些研究将为血管疾病发展的机制基础提供新的见解。