title: Isolation and characterization of highly replicable hepatitis C virus genotype 1a strain HCV-RMT.
abstract: Multiple genotype 1a clones have been reported, including the very first hepatitis C virus (HCV) clone called H77. The replication ability of some of these clones has been confirmed in vitro and in vivo, although this ability is somehow compromised. We now report a newly isolated genotype 1a clone, designated HCV-RMT, which has the ability to replicate efficiently in patients, chimeric mice with humanized liver, and cultured cells. An authentic subgenomic replicon cell line was established from the HCV-RMT sequence with spontaneous introduction of three adaptive mutations, which were later confirmed to be responsible for efficient replication in HuH-7 cells as both subgenomic replicon RNA and viral genome RNA. Following transfection, the HCV-RMT RNA genome with three adaptive mutations was maintained for more than 2 months in HuH-7 cells. One clone selected from the transfected cells had a high copy number, and its supernatant could infect naïve HuH-7 cells. Direct injection of wild-type HCV-RMT RNA into the liver of chimeric mice with humanized liver resulted in vigorous replication, similar to inoculation with the parental patient's serum. A study of virus replication using HCV-RMT derivatives with various combinations of adaptive mutations revealed a clear inversely proportional relationship between in vitro and in vivo replication abilities. Thus, we suggest that HCV-RMT and its derivatives are important tools for HCV genotype 1a research and for determining the mechanism of HCV replication in vitro and in vivo.
authors.affiliation: Advanced Medical Research Laboratory, Mitsubishi Tanabe Pharma Corporation, Kanagawa, Japan ; Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Arai
authors.affiliation: Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Tokunaga
authors.affiliation: Advanced Medical Research Laboratory, Mitsubishi Tanabe Pharma Corporation, Kanagawa, Japan ; Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
authors.forename: Asako
authors.initials: A
authors.lastname: Takagi
authors.affiliation: Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Tobita
authors.affiliation: Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hirata
authors.affiliation: PhoenixBio Co., Ltd., Hiroshima, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ishida
authors.affiliation: PhoenixBio Co., Ltd., Hiroshima, Japan.
authors.forename: Chise
authors.initials: C
authors.lastname: Tateno
authors.affiliation: Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
authors.forename: Michinori
authors.initials: M
authors.lastname: Kohara
mesh_terms: D000818:Animals; D005814:Genes, Viral; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D051379:Mice; D009154:Mutation; D012367:RNA, Viral / Q000235:genetics; D014779:Virus Replication / Q000235:genetics*
chemical_list: D012367:RNA, Viral