Cyclophilin A基因多态性及其介导的炎症反应在冠心病中的作用

【作者】 唐振旺；

【导师】 廖端芳；

【作者基本信息】 南华大学 ， 病理学与病理生理学， 2012， 博士

【摘要】 目的：研究cyclophilinA基因多态性及其作为促炎因子在冠状动脉粥样硬化中的作用，并探讨cyclophilinA调控炎症反应的分子机制。方法：DNA池结合荧光定量PCR技术观察cyclophilinA、TNF-α、IL-6和IL-10各SNP位点多态性与冠心病的相关性。ELISA测定冠心病患者行PCI术前后不同时间段血中cyclophilin A、TNF-α、IL-6和IL-10的水平，观察血中cyclophilin A水平与冠心病炎症状态的相关性。免疫组织化学检测cyclophilin A在冠状动脉粥样硬化斑块和正常组织中的表达差异。Western blot和免疫共沉淀分析在T淋巴细胞中敲除cyclophilinA后对ITK和T-bet表达及活性的影响。结果：冠心病人cyclophilin A829位点AA型、IL-6797位点AG型和910位点AA型高于正常人，其它位点无明显差异。冠心病患者行PCI术后血中cyclophilin A水平和IL-6、TNF-α逐渐降低，而IL-10水平逐渐升高。CyclophilinA在冠状动脉粥样硬化斑块处高表达，从T细胞中敲除cyclophilin A后，ITK的表达和活性降低，而T-bet表达增加。结论：1. CypA829位点的AA基因型突变与冠心病相关。2. CypA在冠心病人血中水平与冠心病炎症状态呈现正相关性，对PCI术后炎症及术后并发症具有指示作用。3. CypA通过抑制ITK活性，阻止T细胞向Th2亚型分化，同时促进T-bet的表达，使之向Th1亚型分化，最终加重冠状动脉粥样硬化的炎症程度。更多还原

【Abstract】 Object To investigate the roles of gene polymorphism and pro-inflammatory activityof cyclophilin A in coronary atherosclerosis, and to explore the mechanisms ofcyclophilin A in inflammatory response.Methods DNA pool combined with quantitative PCR technique to observe thecorrelation between coronary artery disease and polymorphism of cyclophilin A,TNF-alpha, IL-6and IL-10. ELISA to detect the level of cyclophilin A, TNF-alpha,IL-6and IL-10level before and after percutaneous coronary intervention(PCI) incoronary artery disease(CHD) patients, and observed the correlation betweencyclophilin A level and inflammatory state in coronary artery disease.Immunohistochemical to detect the expression of cyclophilin A in coronaryatherosclerotic plaque and normal tissue. Western blot and coimmunoprecipitation toanalyze the effects of cyclophilin A knock-down on expression of ITK and T-bet in Tlymphocytes.Results Genotype and allele frequency of the SNP of M829in cyclophilin A gene hasa significant difference between200patients and200controls. Cyclophilin A829AAwas significantly higher than that of healthy controls. Genotype of797A/G and910A/G in IL-6gene was higher than that of healthy controls. There hasn’t significantdifference between200patients and200controls in the allele frequency of the SNP ofTNF-α gene. The levels of cyclophilin A, IL-6and TNF-α were decreased after PCI inCHD, while IL-10levels gradually increased. Cyclophilin A was highly expressed incoronary atherosclerotic plaques. Expression and activity of ITK was declined whenknock-down of cyclophilin A, while T-bet was increased.Conclusion The polymorphism genotype of cyclophilin A829AA was significantlyhigher than that of healthy controls, may be related to CHD. There was a positivecorrelation between cyclophilin A level and inflammatory state in CHD, cyclophilin Amay be used as a indicator of postoperative inflammation and complications after PCI.Cyclophilin A prevented the differentiation of T cells to Th2subtype by Suppression of ITK activity, while promoting the differentiation to Th1subtype by inducingexpression of T-bet, which aggravated the inflammation in CHD.更多还原