Elucidation of host factors and the associated pathways responsible for cellular permissiveness to hepatitis E virus replication and identification of the potential inhibitors

戊型肝炎病毒(HEV)日益被认为是急性肝炎的主要原因。在免疫功能低下的患者中，HEV会导致慢性肝炎。目前，还没有专门的抗HEV药物可用。靶向与HEV复制相关的细胞因子可能是开发特异性抗HEV药物的方法之一。在这种情况下，细胞培养是必要的。即使接种相同的病毒，PLC/PRF/5细胞的亚克隆对HEV的复制也有不同的透过性，这表明除了病毒本身因素外，细胞因素可能参与了决定宿主对HEV复制的易感性，因此可以作为开发特异性抗HEV药物的靶点。单个PLC/PRF/5细胞的亚克隆对HEV复制的透过性差异高达1万倍。根据高许可和低许可PLC/PRF/5亚克隆的RNA芯片分析结果，筛选出15个上调基因和15个下调基因。对上调和下调的基因进行小干扰RNA(SiRNA)介导的基因沉默，然后使用eHEV-NanKAZ(Primadharsini等人，J Virol 2022)进行筛选和细胞培养评估。在高度许可的亚克隆中沉默四个上调基因中的任何一个会导致HEV复制效率下降，而在许可程度较低的亚克隆中沉默四个下调基因中的任何一个会导致HEV复制效率略有提高。

Hepatitis E virus (HEV) is increasingly recognized as the leading cause of acute hepatitis. In immunocompromised patients, HEV can cause chronic hepatitis. Currently, there is no specific anti-HEV drug available. Targeting cellular factors associated with HEV replication can be one of the methods to develop specific anti-HEV drug. In this context, cell culture is required. Subclones of PLC/PRF/5 cells have variable permissiveness to HEV replication even when inoculated with the same virus, suggesting that aside from viral factor itself, cellular factors might be involved in determining host susceptibility to HEV replication, and therefore, can be the target for development of specific anti-HEV drug.Subclones of a single PLC/PRF/5 cell line demonstrated up to 10,000-folds difference in the permissiveness to HEV replication. Based on the results of RNA microarray analysis of highly permissive and poorly permissive PLC/PRF/5 subclones, 15 upregulated genes and 15 downregulated genes were selected. Small interfering RNA (siRNA)-mediated gene silencing was performed on the upregulated and downregulated genes, followed by screening using eHEV-nanoKAZ (Primadharsini et al., J Virol 2022) and evaluation in cell culture. Silencing of any of four of upregulated genes in highly permissive subclone resulted in decreased HEV replication efficiency, while silencing of any of four downregulated genes in the poorly permissive subclone resulted in slightly increased HEV replication efficiency.