The focus of hepatitis B functional cure, defined as sustained loss of hepatitis B virus (HBV) surface antigen (HBsAg) and HBV DNA from blood, is on eliminating or silencing the intranuclear template for HBV replication, covalently closed circular DNA (cccDNA). However, HBsAg also derives from HBV DNA integrated into the host genome (iDNA). Little is known about the contribution of iDNA to circulating HBsAg with current therapeutics. We applied a multiplex droplet digital PCR assay to demonstrate that iDNA is responsible for maintaining HBsAg quantities in some individuals. Using paired bulk liver tissue from 16 HIV/HBV-coinfected persons on nucleos(t)ide analog (NUC) therapy, we demonstrate that people with larger HBsAg declines between biopsies derive HBsAg from cccDNA, whereas people with stable HBsAg levels derive predominantly from iDNA. We applied our assay to individual hepatocytes in paired tissues from 3 people and demonstrated that the individual with significant HBsAg decline had a commensurate loss of infected cells with transcriptionally active cccDNA, while individuals without HBsAg decline had stable or increasing numbers of cells producing HBsAg from iDNA. We demonstrate that while NUC therapy may be effective at controlling cccDNA replication and transcription, innovative treatments are required to address iDNA transcription that sustains HBsAg production.

中文翻译：

---

整合的乙型肝炎病毒 DNA 在抗病毒治疗期间维持表面抗原的产生


乙型肝炎功能性治愈（定义为血液中乙型肝炎病毒 (HBV) 表面抗原 (HBsAg) 和 HBV DNA 持续丧失）的重点是消除或沉默 HBV 复制的核内模板，即共价闭合环状 DNA (cccDNA)。然而，HBsAg 也源自整合到宿主基因组中的 HBV DNA (iDNA)。对于当前治疗中 iDNA 对循环 HBsAg 的贡献知之甚少。我们应用多重液滴数字 PCR 测定来证明 iDNA 负责维持某些个体的 HBsAg 数量。使用 16 名接受核苷（酸）类似物 (NUC) 治疗的 HIV/HBV 合并感染者的配对大块肝组织，我们证明在活检之间 HBsAg 下降幅度较大的人从 cccDNA 中获得 HBsAg，而 HBsAg 水平稳定的人主要从 iDNA 中获得。我们对 3 个人的配对组织中的单个肝细胞进行了检测，证明 HBsAg 显着下降的个体具有转录活性 cccDNA 的感染细胞相应的损失，而 HBsAg 没有下降的个体则具有稳定或增加数量的从 iDNA 产生 HBsAg 的细胞。我们证明，虽然 NUC 疗法可能有效控制 cccDNA 复制和转录，但需要创新疗法来解决维持 HBsAg 产生的 iDNA 转录。