克罗恩病相关的NOD2及β-防御素-2基因多态性对β-防御素-2表达的影响  

Effect of polymorphisms of Crohn disease related NOD2 gene and human beta-defensin 2 on expression of human beta-defeusin 2

作　　者：姚国鹏[1] 智发朝[1] 张迎春[1] 陈正彦[1] 智佳[1] 林勇[1] 关婧[1] 王继德[1] 姜泊[1] 

机构地区：[1]南方医科大学南方医院消化内科,广州510515

出　　处：《中华消化内镜杂志》2009年第11期584-588,共5页Chinese Journal of Digestive Endoscopy

基　　金：广东省自然科学基金项目（03004770）

摘　　要：目的探讨克罗恩病（Crohndisease，CD）相关的NOD2及人β-防御素-2（humanbeta—defensin2，hBD-2）基因多态性对hBD-2转录活性的影响及主要机理。方法将hBD-2报告基因质粒和NOD2真核表达载体共转染至HEK293T细胞，用脂多糖（LPS）和TNF—α分别孵育刺激后测定hBD-2转录活性变化。结果LPS对hBD-2转录活性有抑制作用（P=0．020），TNF—α可相对升高hBD-2转录活性，呈剂量依赖性（P=0．004）；LPS作用时，NOD2（P268S）改变前后hBD-2的转录活性差异有统计学意义（P=0．008）；hBD-2（-233）改变前后hBD-2的转录活性差异无统计学意义（P=0．053）。在TNF-α（5ng／m1）刺激时，NOD2（P268S）改变前后hBD-2的转录活性差异无统计学意义（P=0．064）；hBD-2（-233）改变前后hBD-2的转录活性差异有统计学意义（P=0．006）；NF—κB抑制剂可显著下调hBD-2转录的激活（P〈0．001）。结论NOD2（P268S）改变能够降低hBD-2的内源性表达；hBD-2（-233）改变导致hBD-2诱生性表达的减少；NF—κB通路可能是hBD-2诱导表达的主要路径。Objective To explore the effects of polymorphisms of Crohn＇s disease related NOD2 gene and human beta-defensin 2 （hBD-2） on transcription of hBD-2 gene and its mechanism. Methods I-IEK293T cells were transfected with hBD-2 gene and NOD2 eukaryotic expression plasmid, and were then stimulated with LPS, TNF-α or BAY 11-7082 （ antagonist of NF-κB） , respectively. Transcriptional activity of hBD-2 was detected afterwards. Results LPS could suppress transcription of hBD-2 （ P = 0. 020） , which was increased by TNF-α in a dose-dependent manner （P = 0. 004）. In the presence of LPS, there was significant difference in transcriptional activity of hBD-2 between wild-NOD2 transfected group and mutated NOD2 （P268S） transfected group （P = 0. 008 ）, but there was no significant difference between wild hBD-2 transfected group and mutated hBD-2 transfected group （ P =0. 053 ）. With the stimulation of TNF-α （5 ng/ml）, there was a significant difference between mutated hBD-2 transfected group and wild hBD-2 transfected group （ P = 0. 006 ）, but no significant difference between wild-NOD2 transfected and mutated NOD2 transfected group was defected （P =0. 064 ）. Pretreatment with BAY 11-7082 before TNF-α （5 ng/ml） significantly inhibited the transcriptional activity of hBD-2 （ P 〈 0.001 ）. Conclusion The polymorphism of NOD2 affects the innate expression of hBD-2, the polymorphism of site in hBD-2 promoter （-233） may lead to significant decline of the inducible expression of hBD-2, and NF-K B might be a key pathway that NOD2 protein mediates the expression of defensin.

关 键 词：Β-防御素-2 CARD15/NOD2 CROHN病 基因多态性 免疫 天然 

分 类 号：R57[医药卫生—消化系统]