乙型肝炎病毒核DNA的分布

StephenW

Distribution of Hepatitis B Virus Nuclear DNA                                 

• Mingming Lia,b,
• Ji A. Sohna and
• Christoph Seegera
  

                  

• aInstitute for Cancer Research, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA                        
• bDepartment of Infectious Diseases, Institute of Hepatology, Central South University, Second Xiangya Hospital, Changsha, Hunan,                           People's Republic of China                        
  

               
                                 

• J.-H. James Ou, Editor
  

                  

• University of Southern California
  

               
                                 ABSTRACT                  

Chronic hepatitis B affects over 300 million people who are at risk of developing liver cancer. The basis for the persistence                     of hepatitis B virus (HBV) in hepatocytes, even in the presence of available antiviral therapies, lies in the accumulation                     of covalently closed circular DNA (cccDNA) in nuclei of infected cells. While methods for cccDNA quantification from liver                     biopsy specimens and cell lines expressing the virus are known, information about cccDNA formation, stability, and turnover                     is lacking. In particular, little is known about the fate of cccDNA during cell division. To fill the gaps in knowledge concerning                     cccDNA biology, we have developed a fluorescence imaging in situ hybridization (FISH)-based assay for the detection of duck hepatitis B virus (DHBV) cccDNA and HBV nuclear DNA in established                     cell lines. Using FISH, we determined the distribution of cccDNA under conditions mimicking chronic infections with and without                     antiviral therapy, which prevents de novo viral replication. Our results showed that the copy numbers of viral nuclear DNA can vary by as much as 1.8 orders of magnitude                     among individual cells and that antiviral therapy leads to a reduction in nuclear DNA in a manner consistent with symmetrical                     distribution of viral DNA to daughter cells.                  

                  

IMPORTANCE A mechanistic understanding of the stability of HBV cccDNA in the presence of antiviral therapy and during cell division                     induced by immune-mediated lysis of infected hepatocytes will be critical for the future design of curative antiviral therapies                     against chronic hepatitis B. Current knowledge about cccDNA stability was largely derived from quantitative analyses of cccDNA                     levels present in liver samples, and little was known about the fate of cccDNA in individual cells. The development of a FISH-based                     assay for cccDNA tracking provided the first insights into the fate of DHBV cccDNA and nuclear HBV DNA under conditions mimicking                     antiviral therapy.                  

               

StephenW

乙型肝炎病毒核DNA的分布

    Mingming Lia，b，Ji A. Sohna和Christoph Seegera

    美国宾夕法尼亚州费城福克斯蔡斯癌症中心癌症研究所
    b中南大学湘雅二医院湖南省长沙市肝病研究所传染病科

    J.-H. James Ou，编辑

    南加州大学

抽象

慢性乙型肝炎影响超过3亿人有发展成肝癌的风险。乙型肝炎病毒（HBV）在肝细胞中持续存在的基础，即使存在可用的抗病毒疗法，也存在于感染细胞核中共价闭合环状DNA（cccDNA）的积累。虽然从肝活组织检查标本和表达病毒的细胞系定量cccDNA的方法是已知的，但缺乏关于cccDNA形成，稳定性和转换的信息。特别是对细胞分裂过程中cccDNA的命运知之甚少。为了填补有关cccDNA生物学知识的空白，我们开发了荧光成像原位杂交（FISH）为基础的检测鸭乙型肝炎病毒（DHBV）cccDNA和HBV核DNA在建立的细胞系。使用FISH，我们确定了cccDNA在模拟有和没有抗病毒治疗的慢性感染的条件下的分布，其防止从头病毒复制。我们的结果显示病毒核DNA的拷贝数在单个细胞中可以变化多达1.8个数量级，并且抗病毒疗法导致以与病毒DNA对子细胞对称分布一致的方式减少核DNA。

重要在抗病毒治疗和免疫介导的感染肝细胞裂解诱导的细胞分裂过程中，对HBV cccDNA稳定性的机制理解对于未来设计针对慢性乙型肝炎的治疗性抗病毒疗法至关重要。目前关于cccDNA稳定性的知识主要来源于对肝脏样品中cccDNA水平的定量分析，而对个体细胞中cccDNA的命运知之甚少。基于FISH的cccDNA追踪检测技术的发展提供了对模拟抗病毒治疗条件下DHBV cccDNA和核酸HBV DNA命运的初步了解。