Mechanisms of Leukocyte Integrin Signaling

白细胞整合素信号传导机制

基本信息

批准号：
7196544
负责人：
Clifford A Lowell
金额：
$ 35.91万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-07-01 至 2010-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7196544
关键词：
76-kDa SH2 domain-containing leukocyte protein Acute Adhesions Adhesives Anti-Inflammatory Agents Anti-inflammatory Back Biochemical Biochemical Genetics Bone Marrow CD18 Antigens Cell membrane Cells Class Complex Data Defect Disease Disease model Disruption Enzymes Family Fc Receptor Fetal Liver Fluorescence Resonance Energy Transfer Hematopoietic stem cells ITAM Infection Inflammation Inflammatory Inflammatory Response Injury Integrin Signaling Pathway Integrins Invaded Knock-out LCP2 gene Laboratories Leukocytes Link Lipids Localized Lung Lymphocyte antigen Macrophage Activation Mediating Methods Microscopy Mitogen-Activated Protein Kinases Modeling Molecular Mus Mutant Strains Mice Mutation Myeloid Cells Pathogenesis Pathway interactions Patients Peptides Pharmaceutical Preparations Process Proteins Reaction Research Personnel Rheumatoid Arthritis Sensitivity and Specificity Series Signal Pathway Signal Transduction Signal Transduction Pathway Signaling Molecule Structure T-Cell Receptor T-Lymphocyte TYROBP gene Techniques Testing Therapeutic Tissues Vascular Endothelium Vasculitis Work adapter protein base cellular transduction diaminopyrimidine human SYK protein in vivo leukocyte activation macrophage mutant neutrophil novel novel strategies programs receptor reconstitution research study response retroviral transduction retroviral-mediated src Homology Region 2 Domain src-Family Kinases syk Family Tyrosine Kinase therapeutic target

项目摘要

DESCRIPTION (provided by applicant): Uncontrolled neutrophil adhesion and activation contributes to significantly to tissue damage in inflammatory diseases such as rheumatoid arthritis and vasculitis. Integrins are the major adhesive receptors on neutrophils that regulate cellular activation. Investigating the basic mechanisms of neutrophil integrin signaling is therefore critical to our understanding of the pathogenesis of inflammatory disease. This application is focused on the "outside-in" integrin signaling pathway that induces neutrophil and macrophage activation. In previous work, we have demonstrated that outside-in integrin signaling is mediated by Src-family and Syk tyrosine kinases. In turn, these enzymes signal to SLP-76 leading to downstream activation of MAP kinases. The sequential involvement of Src-family kinases, Syk and SLP-76 is reminiscent of classical immunoreceptor signaling, such as B or T-cell receptor pathways, which depends on ITAM-containing adapter proteins. In preliminary data, we have found that neutrophils derived from DAP-12-/- FcRgamma-/- mice, which lack the two major ITAM adapters present in myeloid cells, are also completely defective in neutrophil integrin signaling. Based on these observations we hypothesize that leukocyte outside-in integrin signaling mimics classical immunoreceptor signaling pathways. We will test this hypothesis is a series of genetic and biochemical experiments. Using retroviral-mediated fetal liver hematopoietic stem cell transduction, we will introduce a series of mutant versions of Syk and DAP-12 into syk-/- or DAP-12-/- FcRgamma-/- mice that will test whether ITAM-Syk interactions are required for integrin signaling in primary neutrophils and macrophages. We will also test whether beta2 integrins form a complex with ITAM-containing DAP-12 and Syk, using biochemical methods and FRET-based microscopy techniques. If Syk and DAP12/FcRgamma are critical in outside-in integrin signaling, then deficiency of these molecules should result in equivalent defects in inflammatory processes in vivo. We will test this using two disease models that are known to be integrin dependent. If our hypothesis that integrin outside-in signaling mimics immunoreceptor pathways by use of ITAM molecules is validated, this will significantly change the view of integrin function in neutrophil-dependent inflammation. Therapeutic targeting of the integrin outside-in signaling pathway may provide novel classes of anti-inflammatory drugs.

描述（由申请人提供）：不受控制的中性粒细胞粘附和激活显着导致炎症性疾病（例如类风湿关节炎和血管炎）的组织损伤。整合素是调节细胞活化的中性粒细胞上的主要粘合剂受体。因此，研究中性粒细胞整合素信号传导的基本机制对于我们对炎症性疾病发病机理的理解至关重要。该应用集中在诱导中性粒细胞和巨噬细胞激活的“外部”整合素信号通路上。在先前的工作中，我们证明了外部整联蛋白信号传导是由SRC-Family和Syk酪氨酸激酶介导的。反过来，这些酶向SLP-76发出信号，导致MAP激酶的下游激活。 SRC-家庭激酶SYK和SLP-76的顺序参与让人联想到经典的免疫感受器信号传导，例如B或T细胞受体途径，该信号取决于含ITAM的衔接蛋白。在初步数据中，我们发现源自DAP-12 - / - fcrgamma - / - 小鼠的中性粒细胞缺乏髓样细胞中存在的两个主要ITAM适配器，在中性粒细胞整合蛋白信号传导中也完全有缺陷。基于这些观察结果，我们假设白细胞内整合素信号传导模仿经典免疫受体信号通路。我们将检验该假设是一系列遗传和生化实验。使用逆转录病毒介导的胎儿肝造血干细胞转导，我们将在SYK-/ - 或DAP-12 - / - fcrgamma-/ - 鼠标中引入一系列突变版本的SYK和DAP-12，这些突变版将测试ITAM-SYK相互作用是否需要ITAM-SYK的相互作用，而伊塔姆 - Syk相互作用是否需要原发性中性粒和乳突中的整合素信号传递。我们还将使用生化方法和基于FRET的显微镜技术来测试Beta2整合素是否与含ITAM的DAP-12和SYK形成复合物。如果SYK和DAP12/FCRGAMMA在整联蛋白信号传导中至关重要，则这些分子的缺乏应导致体内炎症过程中的等效缺陷。我们将使用已知依赖性蛋白的两个疾病模型对此进行测试。如果我们假设整联蛋白外部信号传导通过使用ITAM分子模仿免疫感受器途径，则将显着改变整联蛋白功能在中性粒细胞依赖性炎症中的观点。整联蛋白外部信号传导途径的治疗靶向可能会提供新型的抗炎药。