Mechanisms Governing Monocyte Recruitment during Periodontal Inflammation

牙周炎症期间单核细胞募集的机制

• 批准号: 7932530
• 负责人: Rebecca Worthylake
• 金额: $ 8.21万
• 依托单位: LSU HEALTH SCIENCES CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-22 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7932530
• 关键词: Actins; Adhesions; Area; Binding; Blood Circulation; CX3CL1 gene; Cell Adhesion Molecules; Cytoskeleton; Data; Development; Disease; Endothelium; GTP Phosphohydrolase Activators; Goals; Inflammation; Inflammatory; Inflammatory Response; Integrins; Kinetics; Leukocytes; Measures; Mediating; Modeling; Molecular; Oral health; Periodontal Diseases; Proteins; Proteomics; Reaction; Recruitment Activity; Regulation; Research Design; Research Personnel; Role; Signal Pathway; Signal Transduction; Testing; Therapeutic; Therapeutic Intervention; Tissues; Up-Regulation; base; chemokine; combat; design; in vivo; migration; monocyte; novel; public health relevance; research study; response; rho; rho GTP-Binding Proteins; trafficking

DESCRIPTION (provided by applicant): Inflammation is a major contributor to periodontal disease, and understanding the molecular mechanisms that govern the inflammatory response is a necessary precursor to the rational design of therapeutics to combat disease. Our overall objective is to discover specific signaling pathways that regulate monocyte recruitment to promote inflammation, and thereby contribute to the development and progression of periodontal disease. Chemokines are the molecular guides for monocyte trafficking throughout the body & the actin cytoskeleton and integrin adhesion are the molecular machinery that respond to the chemokine signals to effect monocyte migration. In our study, we are investigating how a chemokine associated with periodontal disease, CX3CL1, signals through the cytoskeletal regulator, ROCK, to promote monocyte recruitment from the circulation into periodontal tissue. In this proposal, we are pursuing two aspects of this signaling pathway. First, we are asking if CX3CL1-promoted adhesion is mediated by temporal regulation of ROCK activity. Our preliminary data shows that CX3CL1 and inhibition of ROCK both promote adhesion of monocytes to endothelial adhesion molecules. Chemokines are known to regulate ROCK and its upstream Rho GTPase activators, although the kinetics of specific Rho GTPases in response to CX3CL1 have not been investigated. The purpose of this aim will be to test the hypothesis that CX3CL1 signals through distinct Rho GTPases to transiently inhibit ROCK and promote monocyte adhesion to endothelial adhesion molecules. Second, we are investigating novel mechanisms of ROCK signaling by asking how ROCK interacts with a potential downstream effector, Coronin1A. We have identified Coronin1A as a putative ROCK interacting protein through a proteomics-based approach, and recent studies of Coronin1A function in leukocytes reveal an important role for Coronin1A in leukocyte adhesion, spreading and trafficking in vivo. The functional overlap of ROCK and Coronin1A, in combination with our proteomics results, strongly suggests a previously unrecognized functional interaction between these two proteins. The purpose of this aim will be to determine if ROCK binds to Coronin1A directly, or if Coronin1A is a substrate of ROCK. We anticipate that the results of Aim 1 will provide the data needed to convert our correlative relationship between CX3CL1, ROCK and adhesion into a direct mechanistic relationship. Similarly, while the case for interaction between ROCK and Coronin1A is compelling, the experiments in Aim 2 are necessary to provide the critical preliminary data to directly test their interaction. Together, the results of these aims will provide the necessary preliminary data needed to support a successful R01 application investigating the hypothesis that CX3CL1 triggers monocyte recruitment by inducing adhesion mediated by inhibition of ROCK and subsequent activation of Coronin1A. PUBLIC HEALTH RELEVANCE: Inflammation is a large contributor to periodontal disease, and developing strategies to combat pathological inflammatory reactions is a key goal for oral health investigators. Our studies are designed to understand the molecular mechanisms that govern periodontal inflammation, which will provide necessary information for rational development of therapeutic interventions.

描述（由申请人提供）：炎症是牙周病的主要诱因，了解控制炎症反应的分子机制是合理设计治疗方法以对抗疾病的必要前提。我们的总体目标是发现调节单核细胞募集以促进炎症的特定信号通路，从而促进牙周病的发生和进展。趋化因子是单核细胞在全身运输的分子向导，肌动蛋白细胞骨架和整合素粘附是响应趋化因子信号以影响单核细胞迁移的分子机制。在我们的研究中，我们正在研究一种与牙周病相关的趋化因子CX3CL1如何通过细胞骨架调节因子ROCK发出信号，促进单核细胞从循环招募到牙周组织。在本提案中，我们正在研究这一信号通路的两个方面。首先，我们想知道cx3cl1促进的粘附是否通过ROCK活性的时间调节介导。我们的初步数据显示，CX3CL1和抑制ROCK均促进单核细胞对内皮粘附分子的粘附。已知趋化因子可调节ROCK及其上游Rho GTPase激活剂，但尚未研究特异性Rho GTPase响应CX3CL1的动力学。本研究的目的是验证CX3CL1信号通过不同的Rho gtpase短暂抑制ROCK并促进单核细胞粘附内皮粘附分子的假设。其次，我们正在通过询问ROCK如何与潜在的下游效应物Coronin1A相互作用来研究ROCK信号传导的新机制。我们已经通过基于蛋白质组学的方法确定了Coronin1A是一种假定的ROCK相互作用蛋白，最近关于Coronin1A在白细胞中的功能的研究揭示了Coronin1A在体内白细胞粘附、扩散和运输中的重要作用。ROCK和Coronin1A的功能重叠，结合我们的蛋白质组学结果，强烈表明这两种蛋白之间存在以前未被认识到的功能相互作用。目的是确定ROCK是直接与Coronin1A结合，还是Coronin1A是ROCK的底物。我们预计Aim 1的结果将提供将CX3CL1、ROCK和粘附之间的相关关系转化为直接机制关系所需的数据。同样，虽然ROCK和Coronin1A之间相互作用的情况令人信服，但Aim 2中的实验对于提供直接测试它们相互作用的关键初步数据是必要的。总之，这些目标的结果将提供必要的初步数据，以支持成功的R01应用，研究CX3CL1通过抑制ROCK和随后激活Coronin1A介导的诱导粘附来触发单核细胞募集的假设。