Guo Yan, Lan Yu, Jing Yuanyuan, Cai Bin, Gong Hanshi, Zhang Yixin, Duan Yong
Clinical Laboratory, Shaanxi Blood Center, Zhuque Street No.407, Yanta District, Xi'an, Shaanxi 710061, China.
NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, ChangBai Road No.155, Changping District, Beijing 102206, China.
Can J Infect Dis Med Microbiol. 2022 Jul 19;2022:1874435. doi: 10.1155/2022/1874435. eCollection 2022.
The coexistence of hepatitis B virus (HBV) and hepatitis B surface antibodies (anti-HBs) in occult hepatitis B virus infection (OBI) is a contradictory phenomenon, and the underlying mechanism is not fully understood. The characteristics of pre-S/S mutations in OBI genotypes B and C (OBI and OBI) in the presence or absence of anti-HBs were analyzed extensively in this study. . The amino acid substitutions of envelope proteins of 21 OBI strains, including 4 HBs (+) OBI, 6 HBs (-) OBI, 6 HBs (+) OBIc, and 5 HBs (-) OBI samples, were analyzed and fully compared among groups of HBV genotypes and the presence of anti-HBs.
The mutation rates in pre-S1, pre-S2, and S proteins of OBI were significantly higher than wild-type HBV (wt-HBV) genotype C strains, but only the mutation rate of S protein in OBI was significantly higher compared to wild-type HBV genotype B. The mutation rates in S protein of anti-HBs (-) OBI were higher than anti-HBs(+) OBI samples (4.40% vs. 2.43% in genotype B, > 0.05; 6.81% vs. 3.47% in genotype C, < 0.05). For these high-frequency substitutions in the pre-S/S region, the mutations sN40S and sK122R were found in 27.3% and 45.5% of anti-HBs (-) OBI strains, respectively. 7 substitutions were uniquely found in OBI strains and 9 substitutions were commonly detected in OBI and OBI strains.
These results suggested that the mutations might occur randomly and were not selected by antibody pressure.
隐匿性乙型肝炎病毒感染（OBI）中乙型肝炎病毒（HBV）与乙型肝炎表面抗体（抗-HBs）并存是一种矛盾现象，其潜在机制尚未完全明确。本研究广泛分析了在存在或不存在抗-HBs的情况下，OBI基因型B和C（OBI和OBI）中前S/S突变的特征。分析了21株OBI毒株包膜蛋白的氨基酸替换情况，包括4株HBs（+）OBI、6株HBs（-）OBI、6株HBs（+）OBIc和5株HBs（-）OBI样本，并在HBV基因型组和抗-HBs存在情况之间进行了全面比较。
OBI的前S1、前S2和S蛋白的突变率显著高于野生型HBV（wt-HBV）C基因型毒株，但与野生型HBV B基因型相比，仅OBI的S蛋白突变率显著更高。抗-HBs（-）OBI的S蛋白突变率高于抗-HBs（+）OBI样本（B基因型中分别为4.40%对2.43%，>0.05；C基因型中为6.81%对3.47%，<0.05）。对于前S/S区域的这些高频替换，在27.3%和45.5%的抗-HBs（-）OBI毒株中分别发现了sN40S和sK122R突变。在OBI毒株中独特发现了7个替换，在OBI和OBI毒株中共同检测到9个替换。
这些结果表明，这些突变可能是随机发生的，并非由抗体压力选择。
