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：
7156984
负责人：
Stephen Joseph Galli
金额：
$ 41.91万
依托单位：
STANFORD UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1986
资助国家：
美国
起止时间：
1986-09-01 至 2011-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7156984
关键词：
1-Phosphatidylinositol 3-Kinase 2,4-Dinitrophenol 5-(6)-carboxyfluorescein diacetate succinimidyl ester Abbreviations Accounting Address Affect Affinity Allergic Anaphylaxis Antibodies Antigens Atopic Dermatitis Attention Bone Marrow Bromodeoxyuridine Cell Degranulation Cell Survival Cell secretion Chromosomes, Human, Pair 10 Chymase Class Coupling Cues Cyclin-Dependent Kinases Dermal Development Disease Economics 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 Health Systems Agencies Hexosaminidases Histamine Histocytochemistry Homologous Gene Human IgE IgE Receptors Immune response Immunohistochemistry In Vitro Individual Inflammation Inflammatory Interleukin-3 Interleukins Iodine-131 Human Serum Albumin Leukotrienes Lipids MEKs Mediator of activation protein Mitogen-Activated Protein Kinases Molecular Monoclonal Antibodies Mus Mutation Nucleotides Numbers PTEN gene Passive Cutaneous Anaphylaxis Patients Peritoneal Phenotype Phosphotransferases Propidium Diiodide Prostaglandins Prostaglandins D 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 cost cytokine embryonic stem cell human TNF protein in vivo mast cell mutant novel therapeutics phosphatidylinositol 3,4,5-triphosphate receptor response subcutaneous tensin ubiquitin ligase

项目摘要

DESCRIPTION (provided by applicant): 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. MCs are 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 RabGEF1 (Rab 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 RabGEF1 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 Rabgef1-/- 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 RabGEF1 influence MC development, activation and function, and to what extent might these actions of RabGEF1 on MCs account for some of the dramatic phenotypic abnormalities observed in Rabgef1-/- mice? In Aim 1. we will investigate how RabGEF1, 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 RabGEF1-interacting proteins and their downstream effectors in MCs which have been activated via these receptors. In Aim 2, we will define the mechanisms by which RabGEF1 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, RabGEF1 into the tissues of c-kit mutant, KitW/W-v or KitW-sh/W-sh genetically MC-deficient mice (which express wild type RabGEF1). We thus can study the effects of RabGEF1 on MCs in mice in which only the MCs lack, or express mutant forms of, RabGEF1. Elucidating how RabGEF1 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.

描述（由申请人提供）：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，这些疾病在发达国家造成了巨大的疾病负担和经济成本。 MC 对于某些先天免疫反应的最佳表达也至关重要。虽然人们的注意力集中在正向调节 MC 中促炎介质和细胞因子的 IgE 和特异性抗原 (Ag) 依赖性分泌的元件上，但可以抑制此类反应的幅度和/或持续时间的分子机制已经被证实。研究较少。我们最近报道，在 IgE 和特异性 Ag 刺激的 MC 中，RabGEF1（Rab 鸟嘌呤核苷酸交换因子 1）可以负向调节 Ras 依赖性信号通路以及所有三类介质（预形成介质、脂质介质和细胞因子）的分泌。最近，我们发现 RabGEF1 还重要地调节 MC 的反应，这些反应是由 MC 的主要生存、发育和增殖因子 SCF（干细胞因子，c-Kit 配体）引起的。值得注意的是，我们的 Rabgef1-/- 小鼠表现出与 MC 数量增加相关的严重皮肤炎症、真皮 MC 脱颗粒（即“激活”）的证据以及血清中组胺和 IgE 水平增加。我们现在希望解决的核心问题是：RabGEF1 通过什么分子机制影响 MC 的发育、激活和功能，以及 RabGEF1 对 MC 的这些作用在多大程度上解释了 Rabgef1-/- 中观察到的一些显着的表型异常。老鼠？在目标 1 中，我们将研究 RabGEF1 及其各个功能域如何在体外或体内负调节由 FceRI 或 c-Kit（SCF 受体）信号传导诱导的小鼠 MC 激活，并将鉴定和表征 RabGEF1 相互作用MC 中的蛋白质及其下游效应子已通过这些受体激活。在目标 2 中，我们将定义 RabGEF1 在体外和体内调节 MC 的存活、发育、表型和增殖的机制。体内研究将利用我们将缺乏 RabGEF1 或表达突变形式 RabGEF1 的体外衍生 MC 转移到 c-kit 突变体、KitW/W-v 或 KitW-sh/W-sh 基因 MC 的组织中的能力有缺陷的小鼠（表达野生型 RabGEF1）。因此，我们可以研究 RabGEF1 对仅 MC 缺乏 RabGEF1 或表达 RabGEF1 突变形式的小鼠 MC 的影响。阐明 RabGEF1 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 激活和发育调节的理解，这是该项目的长期目标。此类工作还可能有助于开发新的治疗方法来缓解疾病，例如哮喘和特应性皮炎，这些疾病与 IgE 依赖性 MC 激活有关，并且在许多患者中，与受影响组织中 MC 数量的增加有关。