Institute of Blood Transfusion, Chinese Academy of Medical Sciences and Peking Union Medical College, Chengdu, Sichuan, China.
Toronto General Research Institute, University of Toronto, Toronto, Ontario, Canada.
J Med Virol. 2017 Dec;89(12):2173-2180. doi: 10.1002/jmv.24867. Epub 2017 Sep 19.
Type I interferons (IFNs) are a family of primordial cytokines that respond to various pathogen infections including Hepatitis C virus (HCV). Type I IFNs signal through Jak/STAT pathway leading to the production of a few hundred interferon stimulated genes (ISGs). The aim of this study was to explore the role of one of these ISGs, MxA in HCV infection and type I IFN production. Plasmid encoding MxA was cloned into PcDNA3.1-3×tag vector and MxA expression was confirmed both at mRNA (RT-PCR) and protein (Western blot, WB) levels. IFNα and IFNβ productions were quantified by RT-PCR from cell lysate and by ELISA kit from culture medium following MxA over-expression in Huh7.5.1 cells. The activation status of Jak/STAT signaling pathway was examined at three levels: p-STAT1 (WB), interferon sensitive response element (ISRE) activity (dual luciferase reporter gene assay), and levels of ISG expression (RT-qPCR). J6/JFH1 HCV culture system was used to study the role of MxA in HCV replication. Our findings indicated that MxA over-expression inhibited HCV replication and potentiated the IFNα-mediated anti-HCV activity; MxA stimulated the production of IFNα, IFNβ, and enhanced IFNα-induced activation of Jak-STAT signaling pathway. We concluded that MxA is a positive regulator of type I IFN signaling in HCV infection.
I 型干扰素 (IFN) 是一组原始细胞因子,可对包括丙型肝炎病毒 (HCV) 在内的各种病原体感染作出反应。I 型 IFN 通过 Jak/STAT 途径发出信号,导致数百种干扰素刺激基因 (ISG) 的产生。本研究旨在探讨这些 ISG 之一,MxA 在 HCV 感染和 I 型 IFN 产生中的作用。将编码 MxA 的质粒克隆到 PcDNA3.1-3×tag 载体中,并在 mRNA(RT-PCR)和蛋白质(Western blot,WB)水平上确认 MxA 的表达。通过 RT-PCR 从细胞裂解物中定量测定 IFNα 和 IFNβ 的产生,并通过 ELISA 试剂盒从培养基中定量测定 Huh7.5.1 细胞中转染 MxA 后的 IFNα 和 IFNβ 的产生。Jak/STAT 信号通路的激活状态在三个水平上进行了检查:p-STAT1(WB)、干扰素敏感反应元件(ISRE)活性(双荧光素酶报告基因检测)和 ISG 表达水平(RT-qPCR)。使用 J6/JFH1 HCV 培养系统研究了 MxA 在 HCV 复制中的作用。我们的研究结果表明,MxA 过表达抑制 HCV 复制并增强 IFNα 介导的抗 HCV 活性;MxA 刺激 IFNα、IFNβ 的产生,并增强 IFNα 诱导的 Jak-STAT 信号通路的激活。我们得出结论,MxA 是 HCV 感染中 I 型 IFN 信号的正调节剂。