Interferon resistance of hepatitis C virus replicon-harbouring cells is caused by functional disruption of type I interferon receptors.
Hepatitis C virus (HCV) replicon-harbouring cell lines possessing interferon (IFN)-resistant phenotypes have recently been established. These were divided into two classes: partially IFN resistant and highly IFN resistant. Here, the viral and cellular factors contributing to the IFN resistance of HCV replicon-harbouring cells were evaluated. The results revealed that cellular factors rather than viral factors contributed to a highly IFN-resistant phenotype. The possibility of genetic abnormality of the factors involved in IFN signalling was investigated. As a result, nonsense mutations and deletions in type I IFN receptor genes (IFNAR1 and IFNAR2c) were found in replicon-harbouring cells showing a highly IFN-resistant phenotype, but rarely appeared in cells showing a partially IFN-resistant phenotype. Furthermore, similar genetic alterations were also found in IFN-resistant phenotype, replicon-harbouring cell lines obtained additionally by IFN-beta treatment. Moreover, it was shown that ectopic expression of wild-type IFNAR1 in IFN-resistant phenotype, replicon-harbouring cells possessing the IFNAR1 mutant restored type I IFN signalling.
Naka
Kazuhito
K
Department of Molecular Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Takemoto
Kazunori
K
Department of Molecular Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Abe
Ken-Ichi
KI
Department of Molecular Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Dansako
Hiromichi
H
Department of Molecular Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Ikeda
Masanori
M
Department of Molecular Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Shimotohno
Kunitada
K
Department of Viral Oncology, Institute for Virus Research, Kyoto University, 53 Kawara-cho Shogo-in, Sakyo-ku, Kyoto 606-8507, Japan.
Kato
Nobuyuki
N
Department of Molecular Biology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
D024882:Drug Resistance, Viral; D016174:Hepacivirus / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D016898:Interferon-alpha / Q000378:metabolism / Q000494:pharmacology; D016899:Interferon-beta / Q000378:metabolism / Q000494:pharmacology; D007372:Interferons / Q000378:metabolism / Q000494:pharmacology*; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D053633:Receptor, Interferon alpha-beta; D017471:Receptors, Interferon / Q000235:genetics / Q000502:physiology*
C507964:IFNAR1 protein, human; D016898:Interferon-alpha; D008565:Membrane Proteins; D017471:Receptors, Interferon; D053633:Receptor, Interferon alpha-beta; D016899:Interferon-beta; D007372:Interferons