C1 INHIBITOR-MEDIATED PROTECTION FROM ENDOTOXIN SHOCK

C1 抑制剂介导的内毒素休克保护

• 批准号: 6917375
• 负责人: ALVIN E DAVIS
• 金额: $ 47.25万
• 依托单位: IMMUNE DISEASE INSTITUTE, INC.
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6917375
• 关键词: binding sites; complement inhibitors; complement pathway regulation; cytoskeleton; endotoxins; enzyme linked immunosorbent assay; gram negative bacteria; immunopharmacology; immunosuppression; intermolecular interaction; laboratory mouse; leukocyte activation /transformation; lipopolysaccharides; macrophage; microorganism disease chemotherapy; nonhuman therapy evaluation; pharmacokinetics; protein binding; protein structure function; recombinant proteins; septicemia; shock; surface plasmon resonance; vascular endothelium; vascular endothelium permeability

DESCRIPTION (provided by applicant): Infusion of C1 inhibitor (C1INH) protects mice, dogs, rabbits and baboons from gram negative bacterial sepsis and shock. Protection has been assumed to result from inhibition of activation of the complement and/or contact systems. Because C1INH is so effective, we hypothesized that it might bind to LPS, and that this interaction might interfere with the ability of LPS to activate macrophages. Preliminary studies support this hypothesis. Specific Aim 1 will analyze the C1INH-LPS interaction. The binding site will be defined using recombinant mutated C1INH proteins, which will be analyzed for the ability to bind to LPS (ELISA and surface plasmon resonance), to inhibit binding of LPS to, and activation of, macrophages. The ability of C1 INH to protect mice from endotoxin shock will be directly compared with that of other endotoxin antagonists. Specific Aim 2 will define the role of C1INH in protection from LPS-induced endothelial injury. To analyze the effect of C1INH on LPS-induced vascular permeability, endothelial cell cytoskeletal alterations and cell barrier dysfunction will be characterized, as will the ability of C1INH, C1INH mutants and the amino terminal domain to reverse LPS-mediated increased vascular permeability. Specific Aim 3 will characterize the clearance and organ localization of C1INH-LPS complexes in mice. In addition, the internalization and degradation of C1INH-LPS complexes by different cell types will be analyzed in vitro. The effect of C1INH on LPS tolerance in mice (induced by low doses of LPS) will be determined. Lastly, because sepsis models are more biologically relevant to human disease and because some agents that are protective in endotoxin shock models may not be protective (or may even be harmful) in sepsis, Specific Aim 4 will analyze the role of C1INH and C1 INH variants in protection in the cecal ligation/puncture model in mice. These studies will lead to improved understanding of the role played by C1INH in the cbrresistance to gram negative sepsis and endotoxin shock, and may lead to new therapies for these diseases.

描述（由申请人提供）： 输注C1抑制剂（C1INH）可保护小鼠，狗，兔子和狒狒免受革兰氏阴性细菌败血症和休克的侵害。假定保护是由于抑制补体和/或接触系统的激活而产生的。因为C1INH是如此有效，所以我们假设它可能与LPS结合，并且这种相互作用可能会干扰LP激活巨噬细胞的能力。初步研究支持这一假设。具体目标1将分析C1INH-LPS相互作用。结合位点将使用重组突变的C1INH蛋白来定义，该蛋白将分析与LPS结合的能力（ELISA和表面等离子体共振），以抑制LPS与巨噬细胞的结合和激活。 C1 INH保护小鼠免受内毒素休克的能力将直接与其他内毒素拮抗剂进行比较。具体的目标2将定义C1INH在保护LPS引起的内皮损伤中的作用。为了分析C1INH对LPS诱导的血管渗透性的影响，将表征内皮细胞细胞骨架骨骼改变和细胞屏障功能障碍，C1INH，C1INH突变体和氨基末端结构域的能力也将表征，从而反向LPS介导的LPS介导的LPS介导的增加血管持续性。特定的目标3将表征小鼠C1INH-LPS复合物的清除和器官定位。另外，将在体外分析C1INH-LPS复合物对C1INH-LPS复合物的内在化和降解。将确定C1INH对小鼠LPS公差的影响（低剂量LPS​​诱导）。最后，由于败血症模型在生物学上与人类疾病更加相关，并且由于内毒素冲击模型中具有保护性的某些药物在败血症中可能不会具有保护性（甚至可能是有害的），因此特定的目标4将分析C1INH和C1 INH在小鼠中盲肠连接/透射模型中保护中的作用。这些研究将提高人们对C1INH在CBRResistance中对革兰氏阴性败血症和内毒素休克的作用的理解，并可能导致这些疾病的新疗法。