PROCESSING OF ENDOTOXINS BY LIVER MACROPHAGES

肝脏巨噬细胞对内毒素的处理

• 批准号: 6362999
• 负责人: PETER THOMAS
• 金额: $ 23.61万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-03-01 至 2003-08-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6362999
• 关键词: Kupffer's cell; binding proteins; biological signal transduction; endotoxins; laboratory mouse; laboratory rat; lipopolysaccharides; liver metabolism; manganese; monoclonal antibody; nucleic acid probes; protein purification; protein sequence; protein structure function; tissue /cell culture; toxin metabolism; transfection

Infection due to gram negative bacteria is a major clinical problem and bacterial endotoxins in the circulation cause life threatening systemic reactions. Endotoxin is also involved in the pathology of a number of liver diseases including cirrhosis. The liver is the major site of metabolism for gut derived endotoxins. The cells responsible for endotoxin clearance from the portal blood is the liver macrophage (Kupffer cell) and co-operates with hepatocytes in detoxification. Because of continuous chronic exposure to low levels of endotoxin the Kupffer cell response to endotoxin is different to other macrophages and monocytes and the molecular details of endotoxin uptake and response in Kupffer cells in unclear. To investigate this we will: 1) Characterize the structures necessary for the binding of endotoxin to the Kupffer cells. We have identified two novel endotoxin binding proteins of 31 and 34 kD on rat Kupffer cells that are internal proteins that appear to be involved in transducing the signal for the cytokine response. Experiments are designed to purify these proteins and to determine amino acid sequences. We will produce monoclonal antibodies to both the 31 and 34 kD binding proteins using multiple antigenic peptide (MAP) technology. These antibodies will be used to study the functional significance and distribution of these binding proteins. 2) We will identify and clone and sequence the genes encoding the 31 and 34 kD endotoxin binding proteins using peptide sequences to synthesize specific oligonucleotide probes. The sequence data will be used to create a potential domain model for the binding proteins and to examine their structural relationships to other proteins. The cloned genes will also be available for transfection into eukaryotic cells and provide a model to study the biological role of these novel LPS binding proteins. 3) We will determine the role of the 31 and 34 kD binding proteins in signaling events associated with LPS interaction with Kupffer cells and in the secretion of cytokines by Kupffer cells in response to LPS. To examine the protective effects of Mn/++ and other transition metals against endotoxin and their inhibition of LPS binding to the 31 and 34 kD proteins. These studies will increase our understanding of the biological effects of endotoxins and lead to novel therapies against toxic shock.

革兰氏阴性菌感染是一个主要的临床问题， 细菌内毒素进入循环系统会危及生命 反应。内毒素还参与许多疾病的病理学 肝脏疾病，包括肝硬化。肝脏是主要部位 肠道源性内毒素的代谢。负责的细胞 门静脉血内毒素的清除是肝脏巨噬细胞 （库普弗细胞）并与肝细胞合作解毒。 由于持续长期接触低水平的内毒素 枯否细胞对内毒素的反应与其他巨噬细胞不同， 单核细胞以及内毒素摄取和反应的分子细节 库普弗细胞不清楚。为了调查这一点，我们将：1）表征 内毒素与 Kupffer 结合所需的结构 细胞。我们已经鉴定出两种新型内毒素结合蛋白 31 和 大鼠 Kupffer 细胞上的 34 kD 是内部蛋白质，似乎是 参与转导细胞因子反应的信号。 实验旨在纯化这些蛋白质并测定氨基 酸序列。我们将生产针对 31 和 使用多抗原肽 (MAP) 的 34 kD 结合蛋白 技术。这些抗体将用于研究功能 这些结合蛋白的重要性和分布。 2）我们会 鉴定、克隆和测序编码 31 和 34 kD 的基因 使用肽序列合成内毒素结合蛋白 特异性寡核苷酸探针。序列数据将用于 创建结合蛋白的潜在结构域模型并检查 它们与其他蛋白质的结构关系。克隆的基因将 也可用于转染真核细胞并提供 模型来研究这些新型 LPS 结合蛋白的生物学作用。 3) 我们将确定 31 和 34 kD 结合蛋白在 与 LPS 与 Kupffer 细胞相互作用相关的信号事件 库普弗细胞响应 LPS 分泌细胞因子。到 检查 Mn/++ 和其他过渡金属的保护作用 对抗内毒素并抑制 LPS 与 31 和 34 的结合 kD 蛋白质。这些研究将加深我们对 内毒素的生物学效应并导致针对内毒素的新疗法 中毒性休克。

项目成果

Identification of two novel LPS-binding proteins in Kupffer cells: implications in TNF-alpha production.

库普弗细胞中两种新型 LPS 结合蛋白的鉴定：对 TNF-α 产生的影响。

• DOI: 10.1179/096805106x118898
• 发表时间: 2006
• 期刊: Journal of endotoxin research
• 作者: Thomas,Peter;Lazure,DonaldA;Moussa,Runna;Bajenova,Olga;Burke,PeterA;Ganguly,Aniruddha;Forse,RArmour
• 通讯作者: Forse,RArmour

Inhibition of lipopolysaccharide activation of Kupffer cells by transition metals.

• DOI: 10.1016/j.jss.2007.11.726
• 发表时间: 2008-08
• 期刊: The Journal of surgical research
• 作者: P. Thomas;H. Hayashi;D. Lazure;P. Burke;O. Bajenova;A. Ganguly;R. Forse