Team 'Pathophysiology and Therapy of Chronic Viral Hepatitis', Inserm U955, Créteil, France Université Paris-Est, Créteil, France.
Inserm U1085, Institut de Recherche Santé Environnement & Travail (IRSET), Rennes, France Université de Rennes 1, Rennes, France Fédération de Recherche BIOSIT de Rennes, UMS 3480-US18, Rennes, France.
Gut. 2015 Jun;64(6):957-65. doi: 10.1136/gutjnl-2013-305634. Epub 2014 Jul 25.
Chronic HCV infection is associated with the development of hepatic fibrosis. The direct role of HCV in the fibrogenic process is unknown. Specifically, whether HCV is able to infect hepatic stellate cells (HSCs) is debated.
To assess whether human HSCs are susceptible to HCV infection.
We combined a set of original HCV models, including the infectious genotype 2a JFH1 model (HCVcc), retroviral pseudoparticles expressing the folded HCV genotype 1b envelope glycoproteins (HCVpp) and a subgenomic genotype 1b HCV replicon, and two relevant cellular models, primary human HSCs from different patients and the LX-2 cell line, to assess whether HCV can infect/replicate in HSCs.
In contrast with the hepatocyte cell line Huh-7, neither infectious HCVcc nor HCVpp infected primary human HSCs or LX-2 cells. The cellular expression of host cellular factors required for HCV entry was high in Huh-7 cells but low in HSCs and LX-2 cells, with the exception of CD81. Finally, replication of a genotype 2a full-length RNA genome and a genotype 1b subgenomic replicon was impaired in primary human HSCs and LX-2 cells, which expressed low levels of cellular factors known to play a key role in the HCV life-cycle, suggesting that human HSCs are not permissive for HCV replication.
Human HSCs are refractory to HCV infection. Both HCV entry and replication are deficient in these cells, regardless of the HCV genotype and origin of the cells. Thus, HCV infection of HSCs does not play a role in liver fibrosis. These results do not rule out a direct role of HCV infection of hepatocytes in the fibrogenic process.
慢性 HCV 感染与肝纤维化的发展有关。HCV 在纤维发生过程中的直接作用尚不清楚。具体来说,HCV 是否能够感染肝星状细胞(HSCs)存在争议。
评估人 HSCs 是否易感染 HCV。
我们结合了一系列原始的 HCV 模型,包括感染性基因型 2a JFH1 模型(HCVcc)、表达折叠 HCV 基因型 1b 包膜糖蛋白的逆转录病毒假型(HCVpp)和亚基因组基因型 1b HCV 复制子,以及两种相关的细胞模型,来自不同患者的原代人 HSCs 和 LX-2 细胞系,以评估 HCV 是否可以感染/复制 HSCs。
与肝细胞系 Huh-7 相反,传染性 HCVcc 或 HCVpp 均未感染原代人 HSCs 或 LX-2 细胞。HCV 进入所需的宿主细胞因子在 Huh-7 细胞中表达较高,但在 HSCs 和 LX-2 细胞中表达较低,除了 CD81。最后,基因型 2a 全长 RNA 基因组和基因型 1b 亚基因组复制子的复制在原代人 HSCs 和 LX-2 细胞中受损,这些细胞表达已知在 HCV 生命周期中起关键作用的细胞因子水平较低,表明人 HSCs 不利于 HCV 复制。
人 HSCs 对 HCV 感染具有抗性。这些细胞中 HCV 的进入和复制均不足,无论 HCV 基因型和细胞来源如何。因此,HCV 感染 HSCs 不会在肝纤维化中起作用。这些结果并不排除 HCV 感染肝细胞在纤维发生过程中的直接作用。