Augmented epigenetic repression of hepatitis B virus covalently closed circular DNA by interferon-α and small-interfering RNA synergy

作者：Kongying Hu, Wenjing Zai, Mingzhu Xu, H L Wang, Xinluo Song, Chao Huang, Jiangxia Liu, Juan Chen, Qiang Deng, Zhenghong Yuan, Jieliang Chen · 发表于：mBio · 年份：2024 · DOI：10.1128/mbio.02415-24 · 被引用次数：9 · 研究领域：Hepatitis B Virus Studies、RNA Interference and Gene Delivery、HIV Research and Treatment

The persistence of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is a key obstacle for HBV cure. This study aims to comprehensively assess the effect of interferon (IFN) and small-interfering RNA (siRNA) combination on the cccDNA minichromosome. Utilizing both cell and mouse cccDNA models, we compared the inhibitory effects of IFNα, siRNA, and their combination on cccDNA activity and assessed its epigenetic state. IFNα2 treatment alone reduced HBV RNAs, HBeAg, and HBsAg levels by approximately 50%, accompanied by a low-level reconstitution of SMC5/6-a chromatin modulator that restricts cccDNA transcription. HBx-targeting siRNA (siHBx) achieved significant suppression of viral antigens and reconstitution of SMC5/6, but this effect could be reversed by the deacetylase inhibitor Belinostat. The combination of IFN with siHBx resulted in over 95% suppression of virological markers, reduction in epigenetic activation modifications (H3Ac and H4Ac) on cccDNA, and further reduced cccDNA accessibility, with the effect not reversible by Belinostat. In an extracellular humanized IFNAR C57BL/6 mouse model harboring recombinant cccDNA, the effect of combination of clinically used pegylated IFNα2 and GalNac-siHBx was further clarified, indicating a higher and more durable suppression of cccDNA activity compared to either therapy alone. In conclusion, the combination of IFNα and siRNA achieves a more potent and durable epigenetic inhibition of cccDNA activity in cell and mo...