Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany.
German Center for Infection Research (DZIF), partner site Heidelberg, TTU Hepatitis, Heidelberg, Germany.
Sci Rep. 2019 Jul 10;9(1):10021. doi: 10.1038/s41598-019-46493-1.
Human hepatitis delta virus (HDV) causes the most severe form of viral hepatitis. Approximately 15-25 million people are chronically infected with HDV. As a satellite virus of the human hepatitis B virus (HBV), HDV uses the HBV-encoded envelope proteins for egress from and de novo entry into hepatocytes. So far, in vitro production of HDV particles is restricted to co-transfection of cells with HDV/HBV encoding cDNAs. This approach has several limitations. In this study, we established HuH7-END cells, which continuously secrete infectious HDV virions. The cell line was generated through stepwise stable integration of the cDNA of the HDV antigenome, the genes for the HBV envelope proteins and the HBV/HDV receptor NTCP. We found that HuH7-END cells release infectious HDV particles up to 400 million copies/milliliter and support virus spread to co-cultured cells. Due to the expression of NTCP, HuH7-END cells are also susceptible to de novo HDV entry. Virus production is stable for >16 passages and can be scaled up for preparation of large HDV virus stocks. Finally, HuH7-END cells are suitable for screening of antiviral drugs targeting HDV replication. In summary, the HuH7-END cell line provides a novel tool to study HDV replication in vitro.
人类乙型肝炎病毒 delta 型(HDV)是引起病毒性肝炎最严重的形式。大约有 1500 万至 2500 万人患有慢性 HDV 感染。作为乙型肝炎病毒(HBV)的卫星病毒,HDV 使用 HBV 编码的包膜蛋白从肝细胞中逸出和从头进入。到目前为止,HDV 颗粒的体外生产仅限于用 HDV/HBV 编码 cDNA 共转染细胞。这种方法有几个局限性。在这项研究中,我们建立了 HuH7-END 细胞,该细胞持续分泌感染性的 HDV 病毒粒子。该细胞系是通过逐步稳定整合 HDV 抗原基因组、HBV 包膜蛋白基因和 HBV/HDV 受体 NTCP 的 cDNA 产生的。我们发现 HuH7-END 细胞释放高达 4 亿拷贝/毫升的感染性 HDV 颗粒,并支持病毒传播到共培养的细胞。由于 NTCP 的表达,HuH7-END 细胞也容易发生从头感染 HDV。病毒生产稳定超过 16 代,可用于大规模制备 HDV 病毒储备。最后,HuH7-END 细胞适合筛选针对 HDV 复制的抗病毒药物。总之,HuH7-END 细胞系为研究 HDV 体外复制提供了一种新的工具。