CpG-c41分子对TLR7-MyD88依赖型信号通路的交叉干扰作用

Cross-interference of CpG-c41 on TLR7-MyD88-dependent pathway

目的探讨TLR9强力拮抗剂CpG-c41分子对TLR7-MyD88依赖型信号通路的交叉干扰作用。方法体外实验采用ELISA法检测CpG-c41对TLR7激动剂ssRNA83刺激RAW264.7细胞24 h诱发的炎症介质TNF-α和IL-6表达的影响,Western blot检测CpG-c41对TLR7-MyD88依赖型信号通路中IκBα蛋白表达的影响;体内实验采用ELISA法检测CpG-c41对ssRNA83攻击BALB/c小鼠2 h诱发血清中TNF-α和IL-6表达的影响作用。结果体内、体外实验均表明,CpG-c41分子能够显著抑制经ssRNA83刺激诱发TLR7-MyD88依赖型信号通路介导的炎症介质TNF-α和IL-6的释放(P<0.01),体外实验表明抑制作用具有量效关系;而Western blot检测显示在CpG-c41作用下,TLR7-MyD88依赖型信号通路中IκBα的降解受干扰。结论 TLR9强力拮抗剂CpG-c41分子通过干扰TLR7-MyD88依赖型信号通路中IκBα的磷酸化降解,抑制炎症介质的释放,发挥对ssRNA攻击小鼠的免疫保护作用。

Objective To explore the cross-interference effect of toll-like receptor 9 （TLR9） anta-gonist CpG-c41 on TLR7-MyD88-dependent pathway. Methods The levels of TNF-α and IL-6 in the supernatants of RAW264.7 cells （supplied with CpG-c41 simultaneously） treated with TLR7 agonist ssRNA83 were measured by ELISA at 24 h, and IκBα expression mediated by TLR7-MyD88-dependent pathway was assayed by Western blotting. CpG-c41-mediated immune protection of ssRNA83 attacked BALB/c mice was observed according to detection of serum levels of TNF-α and IL-6 by ELISA at 2 h. Results The results of in vitro and in vivo experiments demonstrated that the expression levels of TNF-α and IL-6 were all significantly inhibited （P〈0.01）. The results of in vitro experiment showed a dose-dependent inhibition, and Western blotting results showed that CpG-c41 could interfere with the degradation of IκBα mediated by TLR7-MyD88-dependent pathway. Conclusion CpG-c41 has a cross-interference effect on the degradation of IκBα mediated by TLR7-MyD88-dependent pathway, which consequently inhibits the release of pro-inflammatory cytokines, and protects mice against ssRNA attacking.