产肠毒素大肠杆菌K88诱导仔猪炎症反应的分子机制  

Molecular Mechanism of the Inflammatory Response Induced by Enterotrxigenic E.coli K88 in Piglets

作　　者：李海花[1,2] 朱琪[1,2] 王世琼[1,2] 杨春蕾[1,2] 赵向华[1,2] 乔家运[1,2] 王文杰[1,2] LI Hai-hua ZHU Qi WANG Shi-qiong YANG Chun-lei ZHAO Xiang-hua QIAO Jia-yun WANG Wen-jie(Tianjin Institute of Animal Husbandry and Veterinary Science, Tianjin 300381, China Tianjin Engineering Research Center for Livestock and Poultry Health Breeding, Tianjin 300381, China)

机构地区：[1]天津市畜牧兽医研究所,天津300381 [2]天津市畜禽健康养殖技术工程中心,天津300381

出　　处：《中国畜牧兽医》2017年第1期262-267,共6页China Animal Husbandry & Veterinary Medicine

基　　金：国家自然科学基金(31402087)

摘　　要：为探讨产肠毒素大肠杆菌(ETEC)K88感染仔猪发生炎症反应的分子机制,试验用ETEC K88灌服断奶仔猪,ELISA法检测攻毒后仔猪血清中白细胞介素8(IL-8)含量,实时荧光定量PCR方法检测淋巴结中Toll样受体2(TLR2)、Toll样受体4(TLR4)及其信号通路相关基因(髓样分化因子88(MyD88)、Toll相互作用蛋白(Tollip)、B细胞淋巴瘤因子3(Bcl3))的mRNA相对表达水平。结果发现,仔猪攻毒ETEC K88后6和24h血清IL-8含量和淋巴结TLR2/4的表达水平均极显著或显著高于对照组(P<0.01;P<0.05),且感染后24h显著低于感染后6h(P<0.05);仔猪感染ETEC K88后24h淋巴结中MyD88、Tollip和Bcl3的表达水平均极显著高于对照组(P<0.01),但是感染后6h时与对照组相比均无显著差异(P>0.05)。综上所述,ETEC K88感染仔猪可能是通过TLR2/4-MyD88信号通路产生炎症因子IL-8,促使仔猪出现炎症反应,且该炎症反应可能受Tollip和Bcl3蛋白的调控而被减弱。To investigate the molecular mechanism of the inflammatory response in the piglets in- fected with enterotoxigenic E. coli （ETEC） K88, piglets were infected with ETEC K88, the IL-8 content in serum of piglets were assayed hy ELISA,and the mRNA relative expression levels of TLR2/4 and its signal transduction pathway related genes （MyD88,Tollip and Bcl3） in mesenteric lymph nodes were detected by quantitative Real-time PCR. The results showed that compared with control group,the content of IL-8 in serum and the expressions of TLR2/4 in lymph nodes were all extremely significantly or significantly increased at 6 and 24 h after infection （P〈0.01 ; P〈0. 05） ,and the IL 8 content and TLR2/4 mRNA expression at 24 h after infection were all significantly lower than those at 6 h after infection （P〈0.05）. In addition, the expressions of MyD88, Tollip and Bcl3 in lymph nodes were all extremely significantly increased at 24 h after in- fection compared with control group （P〈0, 01）, but there was no significant difference between experimental group and control group at 6 h after infection （P〉0.05）. In conclusion,ETEC K88 infected piglets might produce inflammatory cytokines IL-8 through the TLR2/4-MyD88 signaling pathway,which could promote the inflammatory reaction in piglets. This inflammatory response might be regulated by Tollip and Bcl3,which could weak the inflammatory intensity in piglets.

关 键 词：大肠杆菌K88 仔猪 炎症反应 Toll-样受体 炎症调控 

分 类 号：S858.28[农业科学—临床兽医学]