Institute for Experimental Virology, TWINCORE Centre for Experimental and Clinical Infection Research, a joint venture between Medical School Hannover (MHH) and Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
Institut für Molekularbiologie, Medizinische Hochschule Hannover, Hannover, Germany.
Liver Int. 2023 Oct;43(10):2116-2129. doi: 10.1111/liv.15655. Epub 2023 Jun 27.
Human pluripotent stem cell (hPSC)-derived hepatocyte-like cells (HLCs) are a valuable model to investigate host-pathogen interactions of hepatitis viruses in a mature and authentic environment. Here, we investigate the susceptibility of HLCs to the hepatitis delta virus (HDV).
We differentiated hPSC into HLCs, and inoculated them with infectious HDV produced in Huh7 . HDV infection and cellular response was monitored by RTqPCR and immunostaining.
Cells undergoing hepatic differentiation become susceptible to HDV after acquiring expression of the viral receptor Na -taurocholate co-transporting polypeptide (NTCP) during hepatic specification. Inoculation of HLCs with HDV leads to detection of intracellular HDV RNA and accumulation of the HDV antigen in the cells. Upon infection, the HLCs mounted an innate immune response based on induction of the interferons IFNB and L, and upregulation of interferon-stimulated genes. The intensity of this immune response positively correlated with the level of viral replication and was dependant on both the JAK/STAT and NFκB pathway activation. Importantly, this innate immune response did not inhibit HDV replication. However, pre-treatment of the HLCs with IFNα2b reduced viral infection, suggesting that ISGs may limit early stages of infection. Myrcludex efficiently abrogated infection and blocked innate immune activation. Lonafarnib treatment of HDV mono infected HLCs on the other hand led to exacerbated viral replication and innate immune response.
The HDV in vitro mono-infection model represents a new tool to study HDV replication, its host-pathogen interactions and evaluate new antiviral drugs in cells displaying mature hepatic functions.
人多能干细胞（hPSC）衍生的肝细胞样细胞（HLC）是研究肝炎病毒在成熟和真实环境中宿主-病原体相互作用的有价值模型。在这里，我们研究了 HLC 对乙型肝炎病毒（HDV）的易感性。
我们将 hPSC 分化为 HLC，并将其接种于在 Huh7 细胞中产生的传染性 HDV。通过 RTqPCR 和免疫染色监测 HDV 感染和细胞反应。
在肝特异性表达病毒受体 Na-牛磺胆酸钠共转运蛋白（NTCP）后，进行肝分化的细胞变得容易感染 HDV。将 HLC 接种 HDV 会导致细胞内检测到 HDV RNA，并在细胞中积累 HDV 抗原。感染后，HLC 基于诱导干扰素 IFNB 和 L，并上调干扰素刺激基因，引发先天免疫反应。这种免疫反应的强度与病毒复制水平呈正相关，依赖于 JAK/STAT 和 NFκB 途径的激活。重要的是，这种先天免疫反应不能抑制 HDV 复制。然而，HLC 用 IFNα2b 预处理可减少病毒感染，表明 ISGs 可能限制感染的早期阶段。Myrcludex 可有效阻断感染并阻止先天免疫激活。另一方面，Lonafarnib 处理单独感染 HDV 的 HLC 会导致病毒复制和先天免疫反应加剧。
HDV 体外单感染模型代表了一种新的工具，可用于研究 HDV 复制、宿主-病原体相互作用，并在显示成熟肝功能的细胞中评估新的抗病毒药物。
