Mast Cell Derived PGD2 and LTC4 in Lung Inflammation

肥大细胞衍生的 PGD2 和 LTC4 在肺部炎症中的作用

基本信息

批准号：
7858449
负责人：
BING K LAM
金额：
$ 47.32万
依托单位：
BRIGHAM AND WOMEN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/7858449
关键词：
1-Phosphatidylinositol 3-Kinase 3-Dimensional Abbreviations Acute Aerosols Affinity Allergens Allergic Antibodies Antigen-Presenting Cells Antigens Arachidonate 5-Lipoxygenase Asthma Attenuated Basophils Binding Sites Bone Marrow Bovine Serum Albumin Breathing Bronchoalveolar Lavage Catalysis Chemicals Chronic Chymase Cutaneous Cyclic AMP Cytosolic Phospholipase A2 Data Development Dinoprostone Down-Regulation EMSA Effector Cell Eicosanoids Eicosatetraenoic Acids Electrophoretic Mobility Shift Assay Embryo Enzymes Esters Flare Forced expiratory volume function G Protein-Coupled Receptor Genes Generations Genetic Transcription Gland Glutathione Glutathione S-Transferase Hematopoietic High Pressure Liquid Chromatography Human Hyperplasia IgE Receptors Immune response Immunoassay Inflammation Inflammatory Inflammatory Response Insulin Receptor Interleukin-3 Interleukin-4 Interleukins Leukotriene A4 Leukotriene C4 Leukotrienes Link Lipopolysaccharides Lung Lung Inflammation Lung diseases Mediating Mediator of activation protein Modeling Movement Mucous body substance Mus NF-kappa B Nuclear Ovalbumin Peptidoglycan Peroxisome Proliferator-Activated Receptors Pertussis Toxin Phase Phosphate Buffer Phosphotransferases Pneumonia Polyacrylamide Gel Electrophoresis Process Prostaglandin D2 Prostaglandin-Endoperoxide Synthase Prostaglandins Protein Kinase C Proteins Pulmonary Function Test/Forced Expiratory Volume 1 Role STAT protein STAT6 Transcription Factor Saline Signal Pathway Signal Transduction Site Sodium Dodecyl Sulfate-PAGE Stat3 protein Stem Cell Factor Stimulus Th2 Cells Therapeutic Agents Thromboxane A2 Receptor Toll-like receptors Transgenic Mice Tumor Necrosis Factor-alpha Tumor Necrosis Factors Up-Regulation Welts X-Ray Crystallography airway hyperresponsiveness airway inflammation airway remodeling alpha helix base crosslink cysteinyl leukotriene receptor 2 cysteinyl-leukotriene cytokine eosinophil human CCXCR1 receptor in vivo inhibitor/antagonist intradermal injection leukotriene D4 receptor leukotriene-C4 synthase lymph nodes mast cell methacholine microbial monomer overexpression prostaglandin D receptor prostaglandin R2 D-isomerase receptor receptor-mediated signaling respiratory response stem three dimensional structure

项目摘要

Mast cells (MCs) to respond to activation by innate stimuli or cross linking of the high-affinity receptor for IgE (FceRI) by generating eicosanoids, particularly the cysteinyl leukotrienes (cysLTs) and prostaglandin (PG) D2, providing a direct link to the inflammatory processes in bronchial asthma. While the role of cysLTs in bronchial asthma is established by the efficacy of therapeutic agents that block their synthesis or their action at the type 1 (CysLT-i) receptor, comparable evidence for PGD2 awaits development of specific inhibitors for human use. Our Preliminary studies now reveal that PGD2 unexpectedly suppresses LTC4 synthase (LTC4S) and LTC4 generation by mouse bone marrow-derived MCs (mBMMCs), and that a microbial signal, eptidoglycan (PGN), induces the expression of LTC4S (but not hematopoietic PGD2 synthase) by mBMMCs. Unlike IL-4, PGN upregulates LTC4S by a signal transducer activator of transcription (STAT)6 independent signaling pathway that likely involves nuclear factor KB (NF-icB) and other Toll-like receptor (TLR)-dependent signals. We hypothesize that (1) that PGD2 inhibits LTC4S function by a DP2 receptor-mediated signal directed predominantly to a post translational mechanism, that PGN upregulates LTC4S expression through NF-KB-dependent transcription and that the PGD2 mediated down regulation of LTC4S action will be dominant over the enhancement action of PGN; (2) that in allergen challenge models of pulmonary inflammation, CysLT1 is more important in the inflammatory response and CysLT2 is more relavent to pulmonary remodeling, and that MC-derived PGD2 and PGE2, through suppression of LTC4S, will counter the effects of cysLTs; and (3) that LTC4S functions as homotrimer with each monomer containing four alpha helixes, and that Arg-51 and Tyr-93 are involved in catalysis while lle-27, Val-35, Val-49, Arg-51, Ala-52, Asn-55, Tyr-59, Tyr-93, Tyr-97, and Ala-112 form the binding sites for LTA4 and GSH. We therefore propose the following Specific Aims: 1) To elucidate the mechanism by which PGN upregulates and PGD2 downregulates the expression of LTC4S in mBMMCs; 2) To examine the in vivo role of LTC4 and PGD2 in mast cell dependent models of airway inflammation and in chronic models with remodeling of airways; and 3) To determine the three-dimensional structure of human LTC4S by X-ray crystallography.

肥大细胞 (MC) 通过产生类二十烷酸，特别是半胱氨酰白三烯 (cysLT) 和前列腺素 (PG) D2，对先天刺激或 IgE 高亲和力受体 (FceRI) 交联的激活作出反应，从而提供与支气管哮喘的炎症过程。虽然 CysLT 在支气管哮喘中的作用是通过阻断其合成或其对 1 型 (CysLT-i) 受体的作用的治疗剂的功效来确定的，但 PGD2 的类似证据仍在等待开发用于人类的特定抑制剂。我们的初步研究现在表明，PGD2 出乎意料地抑制了 LTC4 合酶 (LTC4S) 和小鼠骨髓来源的 MC (mBMMC) 产生 LTC4，并且微生物信号肽聚糖 (PGN) 诱导 LTC4S 的表达（但不诱导造血 PGD2 合酶）的表达。）由 mBMMC 进行。与 IL-4 不同，PGN 通过信号转导转录激活剂 (STAT)6 独立信号通路上调 LTC4S，该信号通路可能涉及核因子 KB (NF-icB) 和其他 Toll 样受体 (TLR) 依赖性信号。我们假设 (1) PGD2 通过 DP2 受体介导的信号抑制 LTC4S 功能，该信号主要针对翻译后机制，PGN 通过上调 LTC4S 表达 NF-KB 依赖性转录，并且 PGD2 介导的 LTC4S 作用下调将比 PGN 的增强作用占主导地位； (2)在肺部炎症的过敏原激发模型中，CysLT1在炎症反应中更重要，CysLT2与肺重塑更相关，并且MC衍生的PGD2和PGE2通过抑制LTC4S，将抵消cysLT的作用； (3) LTC4S 作为同源三聚体，每个单体含有四个 α 螺旋，Arg-51 和 Tyr-93 参与催化，而 lle-27、Val-35、Val-49、Arg-51、Ala-52 、Asn-55、Tyr-59、Tyr-93、Tyr-97 和 Ala-112 形成 LTA4 和 GSH 的结合位点。因此，我们提出以下具体目标： 1) 阐明 PGN 上调和 PGD2 下调 mBMMC 中 LTC4S 的表达； 2) 检查LTC4和PGD2在肥大细胞依赖性气道炎症模型和气道重塑慢性模型中的体内作用； 3)通过X射线晶体学确定人类LTC4S的三维结构。