跨膜型TNF-α抗体抵抗内毒素休克的作用及其机制的研究

项目名称： 跨膜型TNF-α抗体抵抗内毒素休克的作用及其机制的研究

项目编号： No.81471899

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 李卓娅

作者单位： 华中科技大学

项目金额： 72万元

中文摘要： TNF-α有跨膜型（tmTNF-α）和分泌型(sTNF-α)。sTNF-α作为促炎细胞因子在内毒素休克中发挥重要作用，我们的前期工作证实tmTNF-α具有抑炎作用，抑制酶解tmTNF-α的TACE酶可保护大鼠抵抗内毒素休克。然而TACE底物众多，抑制之可能引起副作用。本室自制tmTNF-α单克隆抗体可促进tmTNF-α表达，抑制sTNF-α分泌，提高内毒素休克小鼠的存活率。由于LPS主要通过TLR4信号介导大量炎性介质产生而参与内毒素休克，我们推测此抗体可能通过影响LPS/TLR4信号通路发挥抵抗效应。本项目拟通过体内外实验明确此抗体作用的靶环节及其特征；探索其对LPS/TLR4信号的影响及分子机制；并阐明此抗体通过哪条tmTNF-α信号通路影响LPS/TLR4效应。本研究结果不但有利于阐明tmTNF-α在内毒素性休克中的作用及其机制，而且为开发该抗体的临床应用提供理论依据和实验证据。

中文关键词： 跨模型TNF抗体；内毒素休克；脂多糖；Toll样受体4；信号通路

英文摘要： Tumor necrosis factor-α exists transmembrane form (tmTNF-α) and secretory form (sTNF-α). It has been well known that sTNF-α, as a proinflammatory factor, plays an important role in endotoxin shock. Our previous work demonstrated that tmTNF-α acts as an anti-inflammatory factor and inhibition of ectdomain shedding of tmTNF-α by antisense oligonucleotides of TACE protects rats from endotoxin shock. Since TACE has a lot of substrates, inhibition of TACE may induce side effects. We made a monoclonal antibody specific to tmTNF-α which increases cell surface expression of tmTNF-α and decreases secretion of sTNF-α. Treatment with tmTNF-α antibody enhances survival rate of mice with endotoxin shock. Because LPS induces the production of a large number of inflammatory mediators through TLR4 signaling to participate in this pathological process, we hypothesized that tmTNF-α antibody may affect LPS/ TLR4 signaling and thus resist endotoxin shock by facilitating tmTNF-α expression. In this project, we shall investigate (1) the mechanism(s) by which tmTNF-α antibody works; (2) the effect of tmTNF-α antibody on LPS/ TLR4 signaling and its underlying mechanisms; (3) on which tmTNF-α signal pathways (forward or reverse signaling) tmTNF-α antibody acts to affect LPS/ TLR4 signaling. The results of this project will not only help to clarify the effects of tmTNF-α on endotoxin shock and underlying mechanisms, but also provide experimental evidences and a new clue to develop this antibody for the clinical treatment of this pathological process.

英文关键词： tmTNF antibody;endotoxin shock;Lipopolysaccharide;Toll like receptor 4;signal pathway