Regulation of Mast Cell Development and Function

肥大细胞发育和功能的调节

基本信息

批准号：
7904354
负责人：
Stephen Joseph Galli
金额：
$ 36.61万
依托单位：
STANFORD UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-08-15 至 2011-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7904354
关键词：
1-Phosphatidylinositol 3-Kinase 2,4-Dinitrophenol Abbreviations Accounting Address Affect Affinity Allergic Anaphylaxis Antibodies Antigens Asthma Atopic Dermatitis Attention Bone Marrow Bromodeoxyuridine Cell Degranulation Cell Survival Cell secretion Chromosomes, Human, Pair 10 Chymase Coupling Cues Cyclin-Dependent Kinases Dermal Development Disease Effector Cell Elements Endothelin-1 Esters Exhibits Extracellular Signal Regulated Kinases Extrinsic asthma Fetal Liver Glutathione S-Transferase Goals Green Fluorescent Proteins Guanine Nucleotide Exchange Factors Hexosaminidases Histamine Histocytochemistry Homologous Gene Human IgE IgE Receptors Immune response In Vitro Individual Inflammation Inflammation Mediators Interleukin-3 Interleukins Leukotrienes Lipids MEKs Mediator of activation protein Mitogen-Activated Protein Kinases Molecular Monoclonal Antibodies Mus Mutation Nucleotides PTEN gene Passive Cutaneous Anaphylaxis Patients Peritoneal Phenotype Phosphotransferases Propidium Diiodide Prostaglandins Proteins Proto-Oncogene Protein c-kit Rattus Recombinants Regulation Reporting Rhinitis Role Serine Serum Serum Albumin Signal Pathway Signal Transduction Skin Stem Cell Factor Structure TNF gene Tissues Toll-like receptors Tumor Necrosis Factor-alpha Tumor Necrosis Factors Ubiquitin Ubiquitination Vacuolar Protein Sorting Venous Work Zinc Fingers beta-n-acetylhexosaminidase burden of illness cytokine economic cost embryonic stem cell in vivo mast cell mutant novel therapeutic intervention phosphatidylinositol 3,4,5-triphosphate receptor response subcutaneous tensin ubiquitin ligase

项目摘要

Mast cells (MCs) are major effector cells in IgE antibody-dependent allergic disorders, such as anaphylaxis, allergic rhinitis and atopic asthma, which account for a very large burden of illness and economic costs in the developed world. MCsare also critical for the optimal expression of certain innate immune responses. While much attention has been focused on the elements which positively regulate the IgE- and specific antigen (Ag)-dependent secretion of pro-inflammatory mediators and cytokines from MCs, the molecular mechanisms which can suppress the magnitude and/or duration of such responses have been less studied. We recently reported that RabGEFI (Rajb guanine nucleotide exchange factor 1.) can negatively regulate Ras-dependent signaling pathways, and the secretion of all three classes of mediators (pre-formed, lipid and cytokine), in MCs stimulated with IgE and specific Ag. More recently, we found that RabGEFI also importantly regulates responses in MCs which are elicited by the major survival, developmental and proliferation factor for MCs, SCF (stem cell factor, the c-Kit ligand). Notably, our Rabgefl^' mice exhibit severe inflammation of the skin associated with increased numbers of MCs, evidence of dermal MC degranulation (i.e., "activation"), and increased levels of histamine and IgE in the serum. The central questions which we now wish to address are: By what molecular mechanisms does RabGEFI influence MC development, activation and function, and to what extent might these actions of RabGEFI on MCs account for some of the dramatic phenotypic abnormalities observed in Rabgefl^'mice? In Aim 1. we will investigate how RabGEFI, and its individual functional domains, can negatively regulate mouse MC activation induced by signaling via FceRI or c-Kit (the SCF receptor) in vitro or in vivo, and will identify and characterize RabGEFI-interacting proteins and their downstream effectors in MCswhich have been activated via these receptors. In Aim 2. we will define the mechanisms by which RabGEFI can regulate the survival, development, phenotype & proliferation of MCs in vitro and in vivo. The in vivo studies will take advantage of our ability to transfer in wfro-derived MCs which lack, or express mutant forms of, RabGEFI into the tissues of c-kit mutant, Kitw/w~v or Kit"-3¿"'*" genetically MC-deficient mice (which express wild type RabGEFI). We thus can study the effects of RabGEFI on MCs in mice in which only the MCs lack, or express mutant forms of, RabGEFI. Elucidating how RabGEFI negatively regulates FceRI- or c-Kit-dependent signaling in MCs will increase our understanding of the regulation of MC activation and development, which is the long-term goal of this project. Such work also may help in the development of new therapeutic approaches for the alleviation of diseases, such as asthma and atopic dermatitis, which are associated with IgE-dependent MC activation and, in many patients, with increased numbers of MCs in the affected tissues.

肥大细胞 (MC) 是 IgE 抗体依赖性过敏性疾病的主要效应细胞，例如过敏反应、过敏性鼻炎和特应性哮喘给人们带来了巨大的疾病负担和经济成本 MCs 对于某些先天免疫反应的最佳表达也至关重要。正向调节 IgE 和特异性抗原的元件受到了广泛关注 MC 中 (Ag) 依赖性促炎介质和细胞因子的分泌，分子能够抑制这种反应的幅度和/或持续时间的机制的研究较少。我们最近报道了 RabGEFI（Rajb 鸟嘌呤核苷酸交换因子 1）可以负向调节 Ras 依赖性信号传导途径，以及所有三类介质（预形成介质、脂质介质和介质介质）的分泌最近，我们发现 RabGEFI 还刺激了 IgE 和特异性 Ag 刺激的 MC。重要的是调节 MC 的反应，这些反应是由主要的生存、发育和 MC 增殖因子、SCF（干细胞因子、c-Kit 配体）值得注意的是，我们的 Rabgefl^' 小鼠表现出。与 MC 数量增加相关的严重皮肤炎症，真皮 MC 的证据脱颗粒（即“激活”）以及血清中组胺和 IgE 水平升高。我们现在要解决的问题是： RabGEFI 通过什么分子机制影响 MC 发育、激活和功能，以及 RabGEFI 对 MC 的这些作用在多大程度上可能起作用对于在 Rabgefl^' 小鼠中观察到的一些显着的表型异常？在目标 1 中，我们将进行调查 RabGEFI 及其各个功能域如何负向调节小鼠 MC 诱导的激活通过 FceRI 或 c-Kit（SCF 受体）在体外或体内发出信号，并将识别和表征 MC 中的 RabGEFI 相互作用蛋白及其下游效应子已通过这些蛋白被激活在目标 2 中，我们将定义 RabGEFI 调节存活的机制，体内研究将利用 MC 的体外和体内发育、表型和增殖。我们能够将缺乏 RabGEFI 或表达 RabGEFI 突变形式的 MC 转移到组织中 c-kit 突变体、Kitw/w~v 或 Kit"-3¿"'*" 遗传 MC 缺陷小鼠（表达野生型 RabGEFI）。我们因此可以研究 RabGEFI 对仅 MC 缺乏或表达突变形式的小鼠 MC 的影响阐明 RabGEFI 如何负向调节 MC 中的 FceRI 或 c-Kit 依赖性信号传导。将增加我们对 MC 激活和发育调控的理解，这是长期的该项目的目标也可能有助于开发新的治疗方法。缓解与 IgE 依赖性 MC 相关的疾病，例如哮喘和特应性皮炎激活，并且在许多患者中，受影响组织中的 MC 数量增加。