Mechanism and pathophysiological significance of mast cell regulated exocytosis

肥大细胞调节胞吐作用的机制及病理生理学意义

基本信息

批准号：
8803758
负责人：
Roberto Adachi
金额：
$ 48.7万
依托单位：
UNIVERSITY OF TX MD ANDERSON CAN CTR
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-03-01 至 2016-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8803758
关键词：
2,4-Dinitrophenol Abbreviations Adaptor Signaling Protein Affinity Alleles Allergic Allergic Reaction Allergic inflammation Animals Bacterial Infections Bacterial Pneumonia Biological Assay Bone Marrow Bovine Serum Albumin Bronchoalveolar Lavage Caenorhabditis elegans Calcium Carboxypeptidase Cell Degranulation Cell membrane Cell physiology Cells Cellular biology Chronic Chymase Clinical Colony-forming units Defect Development Disease Electric Capacitance Electron Microscopy Embryo Event Evolution Exocytosis Extrinsic asthma Failure Functional disorder Galactosidase Genes Genetic Recombination Health Histamine Human IgE IgE Receptors Immune Immune response Individual Infection Control Infectious Agent Inflammation Inflammation Mediators Inflammatory Inflammatory Arthritis Interleukins Intervention Intravenous LacZ Genes Leukotrienes Mast Cell Stabilizer Mediating Modeling Morbidity - disease rate Mus Mutant Strains Mice N-ethylmaleimide-sensitive protein Neuroendocrine Cell Neurons Ovalbumin Participant Passive Cutaneous Anaphylaxis Play Process Property Prostaglandins Protein Isoforms Proteinase-Activated Receptors Proteins Proto-Oncogene Protein c-kit Reaction Relative (related person)Resistance Resolution Role S-nitro-N-acetylpenicillamine SNAP receptor Secretory Vesicles Serotonin Serum Albumin Site Staging Stem Cell Factor Synaptosomes TNF gene Testing Therapeutic Toxic effect Tryptase Tumor Necrosis Factor-alpha airway hyperresponsiveness allergic response anti-IgE cromoglycate cytokine embryonic stem cell human disease intraperitoneal lipid mediator mast cell receptor recombinase research study respiratory response stem synaptotagmin syntaxin syntaxin 3 syntaxin 4 syntaxin binding protein 1 therapeutic target trafficking vesicle-associated membrane protein

项目摘要

DESCRIPTION (provided by applicant): Mast cells play important roles in inflammation and innate immune reactions. Activated mast cells release many inflammatory mediators. Some of them are preformed, stored in their secretory granules, and released via degranulation, a form of regulated exocytosis. The importance of degranulation, different to other mast cell responses, in the development and evolution of inflammation is not known. It is accepted that mast cell degranulation should be important in the early allergic response because histamine and serotonin are secreted through this mechanism. However, we have recently shown that mast cell tryptases released during degranulation play important roles in inflammatory arthritis and defense against bacterial infections. The effects of degranulation on the chronic stages of allergic and non-allergic inflammation are not known. Exocytosis is a highly regulated process, and Syntaxins and Munc18 proteins are essential components of the exocytic machinery. Although the precise role of Syntaxins in exocytosis is well known, the identity of the exocytic step controlled by Munc18 proteins remains controversial. Syntaxins-3 and -4, and Munc18-2 and -3 are the main isoforms expressed in mast cells. Munc18-3 regulates Syntaxin-4 and Munc18-2 regulates Syntaxin-3. We have created genetically-modified mice with specific deletions of each of these four genes in their mast cells. Preliminary studies in these mutant mice point to a severe and selective defect in mast cell regulated exocytosis. We plan to study single mast cells from these unique mice at high resolution to uncover the specific exocytic step mediated by each of these Syntaxins and regulated by each of these Munc18 proteins. Additionally, we will be able to describe how two different Syntaxin/Munc18 pairs control the same vesicular trafficking event. Then, moving from single cell to whole animal studies, we will try to end the controversy about the extent and versatility of the effects of mast cell degranulation by studying our mast cell degranulation- deficient mice in models of chronic allergic asthma, inflammatory arthritis, and bacterial pneumonia. Our genetically modified mice may reveal if mast cell degranulation is an attractive and safe therapeutic target for some inflammatory diseases.

描述（由申请人提供）：肥大细胞在炎症和先天免疫反应中起重要作用。活化的肥大细胞释放许多炎症介质。其中一些是预先形成的，存储在其分泌颗粒中，并通过脱粒释放，这是一种调节的胞吐作用形式。在炎症的发展和演变中，脱粒的重要性与其他肥大细胞反应不同。可以接受的是，肥大细胞脱粒在早期的过敏反应中应该很重要，因为组胺和5-羟色胺通过这种机制分泌。但是，我们最近表明，在脱粒过程中释放出的肥大细胞胰蛋白酶在炎症性关节炎和针对细菌感染的防御中起着重要作用。脱粒对过敏性和非过敏性炎症的慢性阶段的影响尚不清楚。胞吐作用是一个高度调节的过程，语法素和MUNC18蛋白是胞外机械的重要组成部分。尽管语法在胞吞作用中的确切作用是众所周知的，但由Munc18蛋白控制的外吞步骤的身份仍然存在争议。语法-3和-4，Munc18-2和-3是在肥大细胞中表达的主要同工型。 MUNC18-3调节Syntaxin-4和Munc18-2调节Syntaxin-3。我们创建了遗传改性的小鼠，其肥大细胞中这四个基因中的每个基因中的每个基因的特异性缺失。这些突变小鼠的初步研究表明肥大细胞调节胞吐作用的严重缺陷。我们计划在高分辨率下研究这些独特的小鼠的单个肥大细胞，以发现由每种语法素介导的特定外囊性步骤并由这些Munc18蛋白调节。此外，我们将能够描述两个不同的语法/Munc18如何控制相同的囊泡贩运事件。然后，从单个细胞到整个动物研究，我们将尝试通过研究慢性过敏性哮喘，炎性关节炎和细菌性肺炎的模型中的肥大细胞脱粒不足的小鼠来结束有关肥大细胞脱粒的影响的争议。我们的转基因小鼠可能会揭示肥大细胞脱粒是否是某些炎症性疾病的有吸引力且安全的治疗靶标。