Departments of Pathology and Laboratory Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario K1H 8M5, Canada.
Virol J. 2014 Feb 7;11:22. doi: 10.1186/1743-422X-11-22.
Hepatitis B virus (HBV) infection has a low rate of chronicity compared to HCV infection, but chronic liver inflammation can evolve to life threatening complications. Experimental data from HBV infected chimpanzees and HBV transgenic mice have indicated that cytotoxic T cells are the main cell type responsible for inhibition of viral replication, but also for hepatocyte lysis during chronic HBV infection. Their lower activation and impaired function in later stages of infection was suggested as a possible mechanism that allowed for low levels of viral replication. The lack of an interferon response in these models also indicated the importance of adaptive immunity in clearing the infection. Increased knowledge of the signalling pathways and pathogen associated molecular patterns that govern activation of innate immunity in the early stages of viral infections in general has led to a re-evaluation of the innate immune system in HBV infection. Numerous studies have shown that HBV employs active strategies to evade innate immune responses and induce immunosuppression. Some of the immune components targeted by HBV include dendritic cells, natural killer cells, T regulatory cells and signalling pathways of the interferon response. This review will present the current understanding of innate immunity in HBV infection and of the challenges associated with clearing of the HBV infection.
乙型肝炎病毒 (HBV) 感染的慢性化率低于丙型肝炎病毒 (HCV) 感染，但慢性肝炎症可发展为危及生命的并发症。来自感染乙型肝炎病毒的黑猩猩和乙型肝炎病毒转基因小鼠的实验数据表明，细胞毒性 T 细胞是抑制病毒复制的主要细胞类型，但也是慢性乙型肝炎感染期间肝细胞裂解的主要细胞类型。在感染的后期，其较低的激活和受损的功能被认为是允许低水平病毒复制的一种可能机制。这些模型中缺乏干扰素反应也表明适应性免疫在清除感染中的重要性。对一般病毒感染早期固有免疫激活的信号通路和病原体相关分子模式的了解增加，导致对乙型肝炎病毒感染中固有免疫系统的重新评估。大量研究表明，乙型肝炎病毒采用主动策略来逃避固有免疫反应并诱导免疫抑制。乙型肝炎病毒靶向的一些免疫成分包括树突状细胞、自然杀伤细胞、T 调节细胞和干扰素反应的信号通路。这篇综述将介绍目前对乙型肝炎病毒感染固有免疫的理解，以及清除乙型肝炎病毒感染所面临的挑战。
