title: Adenovirus vectors lacking virus-associated RNA expression enhance shRNA activity to suppress hepatitis C virus replication.
abstract: First-generation adenovirus vectors (FG AdVs) expressing short-hairpin RNA (shRNA) effectively downregulate the expressions of target genes. However, this vector, in fact, expresses not only the transgene product, but also virus-associated RNAs (VA RNAs) that disturb cellular RNAi machinery. We have established a production method for VA-deleted AdVs lacking expression of VA RNAs. Here, we showed that the highest shRNA activity was obtained when the shRNA was inserted not at the popularly used E1 site, but at the E4 site. We then compared the activities of shRNAs against hepatitis C virus (HCV) expressed from VA-deleted AdVs or conventional AdVs. The VA-deleted AdVs inhibited HCV production much more efficiently. Therefore, VA-deleted AdVs were more effective than the currently used AdVs for shRNA downregulation, probably because of the lack of competition between VA RNAs and the shRNAs. These VA-deleted AdVs might enable more effective gene therapies for chronic hepatitis C.
authors.affiliation: Laboratory of Molecular Genetics, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Pei
authors.affiliation: Department of Infectious Diseases, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan.
authors.forename: Guoli
authors.initials: G
authors.lastname: Shi
authors.affiliation: Laboratory of Molecular Genetics, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan.
authors.forename: Saki
authors.initials: S
authors.lastname: Kondo
authors.affiliation: Department of Infectious Diseases, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ito
authors.affiliation: Laboratory of Molecular Genetics, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Maekawa
authors.affiliation: Laboratory of Molecular Genetics, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Laboratory of Molecular Genetics, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan.
authors.forename: Izumu
authors.initials: I
authors.lastname: Saito
authors.affiliation: Department of Infectious Diseases, Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Laboratory of Molecular Genetics, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Kanegae
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D017498:Adenovirus E1 Proteins / Q000235:genetics; D017503:Adenovirus E3 Proteins / Q000235:genetics; D017504:Adenovirus E4 Proteins / Q000235:genetics; D002460:Cell Line; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000235:genetics*; D057809:HEK293 Cells; D016174:Hepacivirus / Q000235:genetics* / Q000254:growth & development; D019698:Hepatitis C, Chronic / Q000235:genetics / Q000628:therapy*; D006801:Humans; D011401:Promoter Regions, Genetic; D034622:RNA Interference; D034741:RNA, Small Interfering; D012367:RNA, Viral / Q000096:biosynthesis; D016662:Virus Integration / Q000235:genetics; D014779:Virus Replication / Q000235:genetics*
chemical_list: D017498:Adenovirus E1 Proteins; D017503:Adenovirus E3 Proteins; D017504:Adenovirus E4 Proteins; D034741:RNA, Small Interfering; D012367:RNA, Viral