Institut National de la Recherche Scientifique-Centre Armand-Frappier Santé Biotechnologies, Laval, Canada.
Replicor Inc, Montréal, Canada.
PLoS One. 2023 Nov 1;18(11):e0293167. doi: 10.1371/journal.pone.0293167. eCollection 2023.
Chronic hepatitis B remains a global health problem with 296 million people living with chronic HBV infection and being at risk of developing cirrhosis and hepatocellular carcinoma. Non-infectious subviral particles (SVP) are produced in large excess over infectious Dane particles in patients and are the major source of Hepatitis B surface antigen (HBsAg). They are thought to exhaust the immune system, and it is generally considered that functional cure requires the clearance of HBsAg from blood of patient. Nucleic acid polymers (NAPs) antiviral activity lead to the inhibition of HBsAg release, resulting in rapid clearance of HBsAg from circulation in vivo. However, their efficacy has only been demonstrated in limited genotypes in small scale clinical trials. HBV exists as nine main genotypes (A to I). In this study, the HBsAg ORFs from the most prevalent genotypes (A, B, C, D, E, G), which account for over 96% of human cases, were inserted into the AAVS1 safe-harbor of HepG2 cells using CRISPR/Cas9 knock-in. A cell line producing the D144A vaccine escape mutant was also engineered. The secretion of HBsAg was confirmed into these new genotype cell lines (GCLs) and the antiviral activity of the NAP REP 2139 was then assessed. The results demonstrate that REP 2139 exerts an antiviral effect in all genotypes and serotypes tested in this study, including the vaccine escape mutant, suggesting a pangenomic effect of the NAPs.
慢性乙型肝炎仍然是一个全球性的健康问题，全球有 2.96 亿人感染慢性乙型肝炎病毒，面临发展为肝硬化和肝细胞癌的风险。非传染性亚病毒颗粒（SVP）在患者中大量产生，超过传染性 Dane 颗粒，是乙型肝炎表面抗原（HBsAg）的主要来源。它们被认为会耗尽免疫系统，通常认为功能治愈需要从患者血液中清除 HBsAg。核酸聚合物（NAPs）的抗病毒活性导致 HBsAg 释放的抑制，从而导致 HBsAg 在体内循环中迅速清除。然而，它们的疗效仅在小规模临床试验的有限基因型中得到了证明。HBV 存在 9 种主要基因型（A 至 I）。在这项研究中，最常见的基因型（A、B、C、D、E、G）的 HBsAg ORFs 通过 CRISPR/Cas9 基因敲入插入 HepG2 细胞的 AAVS1 安全港。还构建了产生 D144A 疫苗逃逸突变体的细胞系。在这些新的基因型细胞系（GCLs）中证实了 HBsAg 的分泌，并评估了 NAP REP 2139 的抗病毒活性。结果表明，REP 2139 在本研究中测试的所有基因型和血清型中均发挥抗病毒作用，包括疫苗逃逸突变体，这表明 NAPs 具有泛基因组效应。
