Mechanisms of complement induced endothelial dysfunction

补体诱导内皮功能障碍的机制

• 批准号: 7676512
• 负责人: GREGORY L STAHL
• 金额: $ 10万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7676512
• 关键词: Abbreviations; Acetylglucosamine; Affinity; Anaphylatoxin; Anaphylatoxins; Animals; Anti-Inflammatory Agents; Anti-inflammatory; Antibodies; Binding; C3bi; C5a anaphylatoxin receptor; Complement; Complement 3a; Complement 5a; Complement Activation; Complement Factor D; Complement Membrane Attack Complex; Complement component C5; Complex; Data; Deposition; Endothelial Cells; Endothelium; Functional disorder; Funding; Gene Expression; Gene Expression Profile; Genes; Human; Hypoxia; Immunoglobulin M; In Vitro; Inflammation; Inflammatory; Injury; Ischemia; Knockout Mice; Knowledge; Laboratories; Lectin; Literature; Lung; Mannose Binding Lectin; Mannose-Binding Lectin Complement Pathway; Mannose-Binding Lectins; Mediating; Micro Array Data; Modeling; Molecular; Monoclonal Antibodies; Mus; Organ; Oxidative Stress; Pathogenesis; Pathway interactions; Physiological reperfusion; Play; Polymerase Chain Reaction; Proteins; Publications; Rattus; Reagent; Recombinants; Regulation; Reperfusion Injury; Reperfusion Therapy; Reporting; Research; Research Personnel; Resolution; Reverse Transcriptase Polymerase Chain Reaction; Role; Serine Protease; Serum; Staging; Stress; Structure; Surface Plasmon Resonance; Thinking; Time; Tissues; Umbilical vein; Upper arm; Vascular Endothelial Cell; Wing; cobra venom factor; complement pathway; defined contribution; esterase inhibitor; gastrointestinal; human data; ileum; in vivo; mouse model; neutrophil; novel; novel therapeutics; programs; restoration; therapeutic target

DESCRIPTION (provided by applicant): While the exact mechanisms of ischemia/reperfusion injury remain to be elucidated, inhibition of complement activation (e.g., sCRl or Cl esterase inhibitor), depletion of complement components (e.g., cobra venom factor) and complement component (e.g., C3 and C4) knockout mice have revealed an important role of complement in ischemia/reperfusion (I/R) injury. During the previous two funding cycles we have shown that complement is activated on human endothelial cells following oxidative stress and involves the activation of the lectin complement pathway and mannose binding lectin (MBL). During the last cycle, we identifed C5 as a critical complement component involved in gastrointestinal (G) I/R injury. However, the specific pathways involved, the order of pathway activation, and the specific contribution of C5a versus C5b-9 in the setting of GI/R is not well characterized. Reports in the literature suggest that the classical pathway initiates complement activation and mediates tissue injury in GI/R by way of natural antibody (IgM) deposition. Our preliminary data demonstrate complement activation in GI/R is Clq-independent. Preliminary data raise a new potential role for IgM and MBL interactions, perhaps setting stage for a new paradigm in complement activation. This application will investigate the several gaps in our knowledge about complement and its role in mediating tissue injury and inflammation associated with GI/R. Novel anti-complement reagents and knockout mice have been developed for characterizing the role of each complement pathway in GI/R. Specifically we will identify the importance of each specific complement pathway (e.g., lectin, classical and alternative) in GI/R. Previous reports by our group and others have demonstrated that complement activation influences gene expression and we will identify novel pro- and anti-inflammatory genes that are regulated by complement activation and define the role of C5a vs C5b-9 in GI/R, which seems to differ in the ileum compared to other organs. Novel and potential therapeutically useful reagents will be made and used in vivo to establish and validate the genes expressed in vivo and resolution of inflammation in vivo. Our aims are to: 1) Characterize complement pathways involved in complement activation GI/R; 2) define the role of CSa, C3a and C5b-9 in GI/R, 3) characterize the role of MASPs, IgM and MBL complex regulation in GI/R and oxidatively stressed endothelium, and 4) Define/validate the gene expression profile of the lung and ileum following I/R with an emphasis on complement dependent and independent mechansims.

描述(由申请人提供)： 虽然缺血/再灌注损伤的确切机制尚不清楚，但抑制补体激活(如sCR1或氯酯酶抑制剂)、耗尽补体成分(如眼镜蛇蛇毒因子)和补体成分(如C3和C4)基因敲除小鼠已揭示补体在缺血/再灌注损伤中的重要作用。在前两个资助周期中，我们已经证明，在氧化应激后，补体在人内皮细胞上被激活，并涉及凝集素补体途径和甘露糖结合凝集素(MBL)的激活。在最后一个周期中，我们确定C5是参与胃肠道(G)I/R损伤的关键补体成分。然而，涉及的具体途径、途径激活的顺序以及C5a和C5b-9在GI/R中的具体作用尚未得到很好的表征。文献报道表明，在GI/R中，经典途径通过天然抗体(IgM)沉积启动补体激活并介导组织损伤。我们的初步数据表明，GI/R中的补体激活不依赖于Clq。初步数据提出了IgM和MBL相互作用的新的潜在作用，可能为补体激活的新范式奠定了基础。这项应用将调查我们关于补体及其在介导与GI/R相关的组织损伤和炎症中的作用的知识中的几个空白。新的抗补体试剂和基因敲除小鼠已经被开发出来，用于表征每个补体途径在GI/R中的作用。具体地说，我们将确定每种特定的补体途径(例如，凝集素、经典的和替代的)在GI/R中的重要性。以前我们团队和其他人的报告已经证明，补体激活影响基因表达，我们将确定受补体激活调控的新的促炎和抗炎基因，并确定C5a与C5b-9在GI/R中的作用。与其他器官相比，回肠似乎有所不同。新的和潜在的治疗有用的试剂将被制造并用于体内，以建立和验证体内表达的基因和体内炎症的消退。我们的目标是：1)确定补体激活GI/R的补体途径；2)确定CsA、C3a和C5b-9在GI/R中的作用；3)确定MASPs、IgM和MBL复合体在GI/R和氧化应激内皮细胞中的调节作用；4)确定/验证I/R后肺和回肠的基因表达谱，强调补体依赖和独立的机制。