TLR4介导的BV-2细胞抗HCV固有免疫应答机制初步研究

Preliminary study on the mechanism of innate immune response mediated by TLR4 in BV-2 cells anti-HCV

目的:观察BV-2细胞感染HCV后IFN-β、IL-6分泌和TLR4表达相关性,初步探讨TLR4是否介导参与中枢神经系统抗HCV固有免疫应答及其可能机制。方法:将BV-2细胞接种于24孔培养板,贴壁后换用含20%HCV阳性血清的培养液感染细胞,为HCV实验组,同时设正常血清组和空白对照组。应用流式细胞术检测各组BV-2细胞TLR4蛋白水平的表达;用RT-PCR观察阻断TLR4后各组BV-2细胞TLR4mRNA表达变化;用ELISA检测阻断TLR4后各组BV-2细胞IFN-β、IL-6分泌变化。结果:HCV实验组TLR4表达和IFN-β、IL-6分泌均高于正常血清组及空白对照组(P<0.01);阻断TLR4的HCV实验组TLR4mRNA表达及IFN-β、IL-6分泌明显低于非阻断组(P<0.01)。结论:HCV感染中枢神经系统后,TLR4可通过启动下游细胞因子IL-6、IFN-β等的转录和翻译,介导参与宿主抗HCV固有免疫应答过程。

Objective：To explore whether the TLR4 involved in and mediated in the innate immune response in central nervous system anti-HCV and its possible mechanism through observing the correlation between the expression of TLR4 and the secretion of IL-6 and IFN-β in BV-2 cells after HCV infection.Methods：The BV2 cells were seeded in 24-well culture plate and infected with culture solution which contains 20% HCV positive serum,for the HCV experimental group,also have 20% normal serum group and the control group.Meanwhile the expression of TLR4 in every groups were detected at protein levels respectively with Flow cytometry.The changes of TLR4mRNA expression which was observed by RT-PCR and the secretion of IL-6 and IFN-β detected by ELISA in each group when TLR4 were blocked.Results：Both of the TLR4 expression and the secretion of IL6 and IFN-β in HCV experimental group were higher than other groups（P〈0.01）,TLR4mRNA and these cytokines in HCV experimental group were significantly down-regulate when TLR4 were blocked（P〈0.01）.Conclusion：TLR4 may mediate and be involed in the host anti-HCV innate immune response after HCV infecting the central nervous system,through starting transcription and translation of the downstream cytokines IL-6 and IFN-β.