Regulation of MD-2 function and expression

MD-2 功能和表达的调节

基本信息

批准号：
7234403
负责人：
JERROLD P WEISS
金额：
$ 34.96万
依托单位：
UNIVERSITY OF IOWA
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-06-01 至 2009-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7234403
关键词：
Abbreviations Agonist Albumins Antibodies Binding Binding Proteins Biological CD14 gene Calcium Cell surface Cells Complex Coupled Coupling Development Endothelial Cells Endotoxins Epithelial Cells Epithelium Exposure to Fresh Tissue Goals Gram-Negative Bacteria Hanks Balanced Salt Solution Human Immune Immune response Infection Inflammatory Response Invaded Label Lead Link Lipid A Lipopolysaccharides Magnesium Mediator of activation protein Membrane Messenger RNA Molecular Monitor Monoclonal Antibodies Neisseria Pathology Property Proteins Recombinants Regulation Research Personnel Role Signal Transduction Structure Surface TLR4 gene Therapeutic Tissues Toll-Like Receptor 2 Toll-like receptors Transcriptional Activation Umbilical vein Up-Regulation airway epithelium base bronchial epithelium cytokine extracellular improved insight kidney cell lipooligosaccharide lipopolysaccharide-binding protein molecular recognition novel programs prophylactic protein E response toll-like receptor 4

项目摘要

DESCRIPTION (provided by applicant): Highly sensitive host responses to endotoxin (E) are needed for optimal defense against many species of invading Gram-negative bacteria (GNB) but can also lead to significant host pathology when exposure to endotoxin is not adequately controlled. Maximum sensitivity of E signaling requires the ordered interaction of E with several extracellular and cell surface host proteins, including: lipopolysaccharide (LPS)-binding protein (LBP), CD14, MD-2 and Toll-Like Receptor (TLR) 4. Recent observations, including our own, indicate an essential role for MD-2, linking E recognition initiated by LBP and CD14 to activation of TLR4 and determining, at least in certain settings (e.g. airway epithelium), cellular responsiveness to E. The long-term goals of this project are to better understand the molecular basis of innate immune recognition of E and of the coupling of E recognition to induction of pro-inflammatory responses. Our immediate focus will be the structure, function and expression of MD-2, including: 1) further characterization of the structural determinants of E-MD-2 interactions; 2) identification of molecular properties of E:MD-2 complexes required either for potent agonist or antagonist function; and 3) characterization of mechanism(s) regulating MD-2 expression in human airway epithelial cells. We will use metabolically labeled and chromatographically purified E and recombinant E-binding proteins (LBP, sCD14 and MD-2) to analyze protein-E interactions at low, patho-physiologically relevant E concentrations and to preparatively purify protein:E complexes for further structural and functional analyses. MD-2 expression will be monitored by mRNA and protein analyses of fresh tissue and primary cultures of human bronchial epithelium to identify mediators and mechanisms of regulation of MD-2 expression. These studies should yield novel insights concerning the structural determinants of host-E interactions important in innate immune recognition and response to invading GNB. A better understanding of the structure, function and expression of MD-2 should improve understanding of the regulation of host responsiveness to E and could pave the way for development of compounds that, by modulating cellular responses to E, may have prophylactic and/or therapeutic applications.

描述（由申请人提供）：宿主对内毒素（E）的高度敏感反应是针对许多种入侵的革兰氏阴性菌（GNB）的最佳防御所必需的，但当内毒素暴露未得到充分控制时，也可能导致严重的宿主病理。 E 信号传导的最大灵敏度需要 E 与多种细胞外和细胞表面宿主蛋白有序相互作用，包括：脂多糖 (LPS) 结合蛋白 (LBP)、CD14、MD-2 和 Toll 样受体 (TLR) 4. 最新观察结果，包括我们自己的，表明 MD-2 的重要作用，将 LBP 和 CD14 启动的 E 识别与 TLR4 的激活联系起来，并确定至少在某些情况下（例如气道）上皮），细胞对大肠杆菌的反应。该项目的长期目标是更好地了解 E 的先天免疫识别以及 E 识别与促炎症反应诱导的耦合的分子基础。我们当前的重点将是 MD-2 的结构、功能和表达，包括：1）进一步表征 E-MD-2 相互作用的结构决定因素； 2) 鉴定有效激动剂或拮抗剂功能所需的 E:MD-2 复合物的分子特性； 3) 调节人气道上皮细胞中 MD-2 表达的机制的表征。我们将使用代谢标记和色谱纯化的 E 和重组 E 结合蛋白（LBP、sCD14 和 MD-2）来分析低病理生理相关 E 浓度下的蛋白质-E 相互作用，并制备纯化蛋白质：E 复合物以进行进一步的结构分析。和功能分析。通过对人支气管上皮的新鲜组织和原代培养物进行 mRNA 和蛋白质分析来监测 MD-2 表达，以确定 MD-2 表达调节的介质和机制。这些研究应该对宿主-E相互作用的结构决定因素产生新的见解，这对于先天免疫识别和对入侵GNB的反应很重要。更好地了解 MD-2 的结构、功能和表达应提高对宿主对 E 的反应性调节的理解，并可能为开发通过调节细胞对 E 的反应而可能具有预防和/或治疗作用的化合物铺平道路。应用程序。