Gaspareto Karine V, Ribeiro Roberto M, de Mello Malta Fernanda, Gomes-Gouvêa Michele S, Muto Nair H, Romano Camila M, Mendes-Correa Maria C, Carrilho Flair J, Sabino Ester C, Rebello Pinho João R
Laboratory of Tropical Gastroenterology and Hepatology 'João Alves de Queiroz and Castorina Bittencourt Alves', LIM-07, Institute of Tropical Medicine and Department of Gastroenterology, School of Medicine, University of São Paulo, São Paulo, Brazil.
Graduate Program in Biotechnology Interunits (USP/Butantan/IPT), University of São Paulo, São Paulo, Brazil.
Antivir Ther. 2016;21(8):653-660. doi: 10.3851/IMP3057. Epub 2016 Jun 17.
As a result of increased understanding of the HCV life cycle, a new generation of drugs known as direct-acting antivirals (DAAs) was developed and is constantly being improved. At baseline, HCV variants resistant to DAA therapy may pre-exist, increasing the likelihood of treatment failure. The aim of this study was to investigate the presence of resistance-associated variants (RAVs) in treatment-naive patients infected with HCV subtypes 1a and 1b.
Next-generation sequencing was used to assess the frequencies of NS3-4A, NS5A and NS5B RAVs in 100 HCV monoinfected DAA-naive patients (HCV-1a: n=51; HCV-1b: n=49).
Complete HCV sequence information was obtained for most samples. RAVs were detected in the NS3-4A (T54S, V55A, Q80K and R155K), NS5A (Q30H/R, H58P and Y93C/H/N) and NS5B (A421V) regions in 10%, 22% and 8%, respectively, of patients infected with HCV subtype-1a. Among the patients infected with HCV subtype-1b, mutations in the NS3-4A (F43I, T54S, Q80H, D168E and M175L), NS5A (L28M, R30Q, L31M, Q54H, A92T and Y93H) and NS5B (L159F, C316N, A421V and S556G) regions were observed in 12%, 53% and 31% of patients, respectively.
High-throughput DNA sequencing allows an easier and more complete analysis of DAA RAVs, including mutations that represent only a minor variant of the whole viral population. RAVs to the three different classes of DAAs were found in our population. The characterization of their profile in the circulating virus is relevant to determine the better treatment option for infected individuals or to guide the implementation of treatment policies.
由于对丙型肝炎病毒（HCV）生命周期的认识不断加深，新一代被称为直接作用抗病毒药物（DAAs）的药物得以研发并持续改进。在基线时，可能预先存在对DAA治疗耐药的HCV变异株，这增加了治疗失败的可能性。本研究的目的是调查初治的感染HCV 1a和1b亚型患者中耐药相关变异（RAVs）的存在情况。
采用新一代测序技术评估100例单纯HCV感染且未接受过DAA治疗的患者（HCV-1a：n = 51；HCV-1b：n = 49）中NS3-4A、NS5A和NS5B RAVs的频率。
大多数样本获得了完整的HCV序列信息。在感染HCV 1a亚型的患者中，分别有10%、22%和8%的患者在NS3-4A（T54S、V55A、Q80K和R155K）、NS5A（Q30H/R、H58P和Y93C/H/N）和NS5B（A421V）区域检测到RAVs。在感染HCV 1b亚型的患者中，分别有12%、53%和31%的患者在NS3-4A（F43I、T54S、Q80H、D168E和M175L）、NS5A（L28M、R30Q、L31M、Q54H、A92T和Y93H）和NS5B（L159F、C316N、A421V和S556G）区域观察到突变。
高通量DNA测序能够更轻松、更全面地分析DAA RAVs，包括那些仅占整个病毒群体一小部分变异的突变。在我们的研究人群中发现了对三类不同DAA的RAVs。对其在循环病毒中的特征进行描述，对于确定感染个体的更佳治疗方案或指导治疗政策的实施具有重要意义。
