The amino acid substitutions rtP177G and rtF249A in the reverse transcriptase domain of hepatitis B virus polymerase reduce the susceptibility to tenofovir
The amino acid substitutions rtP177G and rtF249A in the reverse transcriptase domain of hepatitis B virus polymerase reduce the susceptibility to tenofovir
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DOI：
10.1016/j.antiviral.2012.12.007
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发表时间：
2013-02-01
影响因子：
7.6
通讯作者：
Chen, Xinwen
中科院分区：
文献类型：
--
作者：
Qin, Bo;Budeus, Bettina;Chen, Xinwen
核苷/核苷酸类似物的长期抗病毒治疗已常规用于治疗慢性B肝炎病毒（HBV）感染，但可能导致出现耐药病毒突变体。然而，替诺福韦（TDF）的HBV耐药突变仍然存在争议。据推测，TDF耐药的遗传屏障可能对HBV很高。我们询问HBV聚合酶中选择性的氨基酸替换是否可以降低对TDF的易感性。通过生物信息学分析，筛选出HBV聚合酶的一系列氨基酸进行突变。在体外和体内测定突变HBV克隆的复制能力和对TDF的敏感性。其中包括19个HBV聚合酶突变，这些突变不同程度地损害了HBV基因组的复制能力。rtL 77 F（sS 69 C）、rtF 88 L（sF 80 Y）和rtP 177 G（sR 169 G）突变也显著影响HBsAg表达。发现带有rtP 177 G和rtF 249 A的HBV突变体在体外对TDF的敏感性降低，耐药指数分别为2.53和12.16。基于流体动力学注射的体内模型中的测试揭示了TDF对野生型和突变型HBV基因组的抗病毒作用，并证实了突变型HBV对TDF的敏感性降低。(C)2012爱思唯尔有限公司版权所有。
Long term antiviral therapy with nucleoside/nucleotide analogs have been routinely used to treat chronic hepatitis B virus (HBV) infection but may lead to the emergence of drug-resistant viral mutants. However, the HBV resistance mutations for tenofovir (TDF) remain controversial. It is speculated that the genetic barrier for TDF resistance may be high for HBV. We asked whether selected amino acid substitutions in HBV polymerase may reduce susceptibility to TDF. A series of amino acids in HBV polymerase were selected based on bioinformatics analysis for mutagenesis. The replication competence and susceptibility to TDF of the mutated HBV clones were determined both in vitro and in vivo. nineteen mutations in HBV polymerase were included and impaired the replication competence of HBV genome in different degrees. The mutations at rtL77F (sS69C), rtF88L (sF80Y), and rtP177G (sR169G) also significantly affected HBsAg expression. The HBV mutants with rtP177G and rtF249A were found to have reduced susceptibility to TDF in vitro with a resistance index of 2.53 and 12.16, respectively. The testing in in vivo model based on the hydrodynamic injection revealed the antiviral effect of TDF against wild type and mutated HBV genomes and confirmed the reduced the susceptibility of mutant HBV to TDF. (C) 2012 Elsevier B.V. All rights reserved.