MOLECULAR ANALYSIS OF ENDOTOXIN RECEPTOR FUNCTION

内毒素受体功能的分子分析

• 批准号: 6395883
• 负责人: Theo N Kirkland
• 金额: $ 15.89万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2000-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6395883
• 关键词: Baculoviridae; CD antigens; X ray crystallography; carbohydrate receptor; cellular pathology; endotoxins; lipopolysaccharides; molecular pathology; nuclear magnetic resonance spectroscopy; protein structure function; receptor binding; septic shock; surface antigens; tissue /cell culture

Septic shock is a highly lethal syndrome triggered by bacterial toxins. A major leap in our understanding of the pathogenesis of septic shock has been the discovery of LPS receptor protein on cells and in the plasma. CD14 is a 55 kDa glycophosphatidylinositol-linked protein surface expressed on the surface of macrophages and polymorphonuclear leucocytes. It also circulates in the plasma. Both membrane and soluble CD14 are critical parts of the LPS recognition system in human beings. Macrophages are stimulated via CD14 to make cytokines, enzymes and a variety of other responses to LPS. Other stimulatory bacterial products, such as peptidoglycan and lipoprotein from Gram-positive bacteria and lipoarabinomannan from mycobacteria also stimulate responses via CD14. Soluble CD14 complexed with LPS stimulates endothelial cells, smooth muscle cells, astrocytes and mesangial cells to express ICAM, ELAM, E- selectin, to make cytokines and nitrous oxide. Over the past five years, we have described some of the critical regions within the N-terminal half of CD14. CD14 is not homologous to other LPS binding proteins. Our hypothesis is that determining the specific structural features of CD14 which encode the various functions of CD14 will yield novel and meaningful information about LPS-protein interactions and the ensuing activation of cells. It is our goal to define the structural features of CD14 which determine its functions. The specific aims of this proposal are: 1. To determine the structural regions of CD14 which enable CD14 to bind lipopolysaccharides, interact with LBP, initiate cellular activation of cells expressing mCD14, enable internalization of LPS-LBP complexes, activate cells via the sCD14-LPS-dependent pathway; 2. To test whether the structural features of CD14 which recognize LPS are also involved in recognizing the surface molecules of Gram-positive microorganisms 3. To determine the three dimensional structure of CD14 by multidimensional NMR and X-ray crystallography we believe that better understanding of the structural domains of CD14 may allow design of new therapeutic strategies for the treatment of septic shock. Since septic shock currently has a mortality rate of 50%, and is a common occurrence in hospitalized patients, effective therapy would be a major medical advance.

感染性休克是一种由细菌毒素引发的高致死性综合征。 我们对感染性休克发病机制认识的重大飞跃 是在细胞上发现了LPS受体蛋白， 等离子体CD 14是一种55 kDa的糖磷脂酰肌醇连接蛋白 在巨噬细胞和多形核细胞表面表达 白细胞它也在血浆中循环。膜和可溶性 CD 14是人类LPS识别系统的关键部分。 巨噬细胞通过CD 14刺激，产生细胞因子、酶和细胞因子。 对LPS的各种反应。其他刺激性细菌产品， 例如来自革兰氏阳性细菌肽聚糖和脂蛋白， 来自分枝杆菌的脂阿拉伯甘露聚糖也通过CD 14刺激应答。 可溶性CD 14与LPS复合刺激内皮细胞，平滑 肌细胞、星形胶质细胞和系膜细胞表达ICAM、ELAM、E- 选择素，制造细胞因子和一氧化二氮。在过去的五年里， 我们已经描述了N-末端内的一些关键区域， CD 14的一半。CD 14与其他LPS结合蛋白不同源。我们 一种假设是确定CD 14的特定结构特征， 其编码CD 14的各种功能， 关于LPS-蛋白质相互作用的有意义的信息， 激活细胞。我们的目标是确定 CD 14决定其功能。具体目标是 建议如下：1.为了确定CD 14的结构区域， 使CD 14能够结合脂多糖，与LBP相互作用， 表达mCD 14的细胞的细胞活化，使内化成为可能 LPS-LBP复合物，通过sCD 14-LPS依赖性激活细胞 路径; 2.为了检测CD 14的结构特征， 识别LPS也参与识别 革兰氏阳性微生物3.为了确定三维的 CD 14多维NMR和X射线晶体学结构研究 相信更好地理解CD 14的结构域可以 允许设计新的治疗策略用于治疗脓毒症 冲击.由于感染性休克目前的死亡率为50%， 这在住院患者中很常见，有效的治疗将 是医学上的一大进步