title: Baseline quasispecies selection and novel mutations contribute to emerging resistance-associated substitutions in hepatitis C virus after direct-acting antiviral treatment.
abstract: Resistance-associated substitutions (RASs) in hepatitis C virus (HCV) appear upon failure of treatment with direct-acting antivirals (DAAs). However, their origin has not been clarified in detail. Among 11 HCV genotype 1b patients who experienced virologic failure with asunaprevir (ASV)/daclatasvir (DCV), 10 had major NS5A L31M/V-Y93H variants after treatment. L31M/V-Y93H variants were detected as a minor clone before therapy in 6 patients and were the most closely related to the post-treatment variants by phylogenetic tree analysis in 4 patients. Next, to consider the involvement of a trace amount of pre-existing variants below the detection limit, we analysed human hepatocyte chimeric mice infected with DAA-naïve patient serum. L31V-Y93H variants emerged after treatment with ledipasvir (LDV)/GS-558093 (nucleotide NS5B inhibitor) and decreased under the detection limit, but these variants were dissimilar to the L31V-Y93H variants reappearing after ASV/DCV re-treatment. Finally, to develop an infection derived from a single HCV clone, we intrahepatically injected full-genome HCV RNA (engineered based on the wild-type genotype 1b sequence) into chimeric mice. A new Y93H mutation actually occurred in this model after LDV monotherapy failure. In conclusion, post-treatment RASs appear by 2 mechanisms: the selection of pre-existing substitutions among quasispecies and the generation of novel mutations during therapy.
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Yugo
authors.initials: Y
authors.lastname: Kai
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Hayato
authors.initials: H
authors.lastname: Hikita
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Morishita
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Murai
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Tasuku
authors.initials: T
authors.lastname: Nakabori
authors.affiliation: Hyogo Prefectural Nishinomiya Hospital, Nishinomiya, Japan.
authors.forename: Sadaharu
authors.initials: S
authors.lastname: Iio
authors.affiliation: Kansai Rosai Hospital, Amagasaki, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Hagiwara
authors.affiliation: Ikeda Municipal Hospital, Ikeda, Japan.
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Imai
authors.affiliation: Minoh City Hospital, Minoh, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Tamura
authors.affiliation: Itami City Hospital, Itami, Japan.
authors.forename: Syusaku
authors.initials: S
authors.lastname: Tsutsui
authors.affiliation: Suita Municipal Hospital, Suita, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Naito
authors.affiliation: Saso Hospital, Nishinomiya, Japan.
authors.forename: Meiko
authors.initials: M
authors.lastname: Nishiuchi
authors.affiliation: Department of Hepatology, Sendai Kousei Hospital, Sendai, Japan.
authors.forename: Yasuteru
authors.initials: Y
authors.lastname: Kondo
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Takanobu
authors.initials: T
authors.lastname: Kato
authors.affiliation: Department of Laboratory Animal Research, Central Institute for Experimental Animals, Kawasaki, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suemizu
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Ryoko
authors.initials: R
authors.lastname: Yamada
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Tsugiko
authors.initials: T
authors.lastname: Oze
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yakushijin
authors.affiliation: Osaka Rosai Hospital, Sakai, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Hiramatsu
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Sakamori
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Tomohide
authors.initials: T
authors.lastname: Tatsumi
authors.affiliation: Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Takehara
mesh_terms: D000818:Animals; D044966:Anti-Retroviral Agents / Q000494:pharmacology; D002219:Carbamates; D024882:Drug Resistance, Viral / Q000235:genetics*; D019143:Evolution, Molecular; D016174:Hepacivirus / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D006526:Hepatitis C / Q000188:drug therapy / Q000821:virology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology / Q000627:therapeutic use; D007546:Isoquinolines / Q000494:pharmacology / Q000627:therapeutic use; D051379:Mice; D009154:Mutation; D010802:Phylogeny; D011759:Pyrrolidines; D012641:Selection, Genetic; D013449:Sulfonamides / Q000494:pharmacology / Q000627:therapeutic use; D014633:Valine / Q000031:analogs & derivatives
chemical_list: D044966:Anti-Retroviral Agents; D002219:Carbamates; D007093:Imidazoles; D007546:Isoquinolines; D011759:Pyrrolidines; D013449:Sulfonamides; D014633:Valine; C549273:daclatasvir; C571889:asunaprevir