Abstract：
High levels of hepatitis B virus (HBV) surface antigen (HBsAg) in the blood of chronic HBV carriers are considered to drive the exhaustion of antigen-specific T and B lymphocytes and thus responsible for the persistence of infection. Accordingly, therapeutic elimination of HBsAg may facilitate the activation of adaptive antiviral immune responses against HBV and achieve a functional cure of chronic hepatitis B. We discovered recently that an amphipathic alpha helix spanning W156 to R169 of HBV small envelope (S) protein plays an essential role in the morphogenesis of subviral particles (SVPs) and metabolism of S protein. We thus hypothesized that pharmacological disruption of SVP morphogenesis may induce intracellular degradation of S protein and reduce HBsAg secretion. To identify inhibitors of SVP biogenesis, we screened 4417 bioactive compounds with a HepG2-derived cell line expressing HBV S protein and efficiently secreting small spherical SVPs. The screen identified 24 compounds that reduced intracellular SVPs and secreted HBsAg in a concentration-dependent manner. However, 18 of those compounds inhibited the secretion of HBsAg and HBeAg in HBV replicon transfected HepG2 cells at similar efficiency, suggesting each of those compounds may disrupt a common cellular function required for the synthesis and/or secretion of these viral proteins. Interestingly, lycorine more efficiently inhibited the secretion of HBsAg in HepG2 cells transfected with HBV replicons, HepG2.2.15 cells and HBV infected - HepG2 cells expressing sodium taurocholate cotransporting polypeptide (NTCP). The structure activity relationship and antiviral mechanism of lycorine against HBV have been determined.
摘要：
慢性HBV携带者血液中高水平的乙型肝炎病毒（HBV）表面抗原（HBsAg）被认为是驱动抗原特异性T和B淋巴细胞的耗尽，从而导致感染的持续存在。因此，治疗性消除HBsAg可能有助于激活针对HBV的适应性抗病毒免疫反应，并实现慢性乙型肝炎的功能性治愈。我们最近发现，跨越W156至R169的HBV小包膜（S）蛋白的两亲性α螺旋在亚病毒颗粒（SVPs）的形态发生和S蛋白的代谢中起着至关重要的作用。因此，我们假设SVP形态发生的药理学破坏可能会诱导S蛋白的细胞内降解并减少HBsAg分泌。为了鉴定SVP生物发生的抑制剂，我们筛选了4,417生物活性化合物与HepG2衍生的细胞系表达HBVS蛋白和有效分泌小球形SVPs。筛选确定了24种化合物，以浓度依赖性方式减少细胞内SVPs和分泌HBsAg。然而,其中18种化合物以相似的效率抑制HBV复制子转染的HepG2细胞中HBsAg和HBeAg的分泌，这些化合物中的每一种都可能破坏合成和/或分泌这些病毒蛋白所需的共同细胞功能。有趣的是,lycorine更有效地抑制HBV复制子转染的HepG2细胞中HBsAg的分泌，HepG2.2.15细胞和HBV感染-HepG2细胞表达牛磺胆酸钠共转运多肽（NTCP）。已经确定了石蒜碱对HBV的结构活性关系和抗病毒机制。
