[Investigating the inhibitory effects of interferon-alpha on the replication of hepatitis C virus replicon].
OBJECTIVE
To investigate the inhibitory effects of interferon-alpha (IFN-alpha) on HCV replicon and evaluate the expressing levels of signal transducer and activator of transcription genes (STAT1 and STAT2) and IFN-alpha stimulated genes (ISGs) which may mediate the inhibitory effects of IFN-alpha on HCV.


METHODS
Firstly HCV replicon cell culture system was established by transfecting HCV replicon RNA transcribed in vitro into Huh7 cells and screening with G418. Secondly, the established HCV replicon cells were treated with various concentrations of IFN-alpha (0, 10, 25, 50, 100, 250, 500, 750, 1000, 2500, and 5000 IU/ml) for 72 h or treated with 1000 IU/ml of IFN-alpha for different lengths of time (0, 24, 48, 72, 96 h), then the levels of HCV RNA and NS5A protein in these cells were examined by semi-quantitative RT-PCR and Western blot respectively.


RESULTS
IFN-alpha could effectively inhibit HCV RNA replication. 10 IU/ml or 25 IU/ml of IFN-alpha could lead to about 68% and 75% of HCV-RNA reduction respectively. The cells treated with 1000 IU/ml IFN-alpha for 24 h or 96 h had about 75% and 88% of HCV RNA reduction compared with the cells of control, demonstrated that the inhibitory effects of IFN-alpha on HCV replicon are in dose and time dependent manners. The expressions of antiviral ISGs-PKR, 2'5'OAS, G1P3, ISG20 and ISGF3gamma are strongly induced by IFN-alpha.


CONCLUSIONS
HCV replicons were sensitive to IFN-alpha treatment. The inhibitory effects of IFN-alpha on HCV RNA and NS5A are both dose and time dependents. PKR, 2'5'OAS, G1P3, ISG20 and ISGF3gamma may mediate the inhibitory effects of IFN-alpha on HCV replicon replication.
Jia
Yin-tang
YT
Institute of Hepatology, People's Hospital, Peking University, Beijing 100044, China.
Wei
Lai
L
Jiang
Dong
D
Cong
Xu
X
Fei
Ran
R
D016174:Hepacivirus / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D016898:Interferon-alpha / Q000494:pharmacology*; D008113:Liver Neoplasms / Q000473:pathology / Q000821:virology*; D012367:RNA, Viral / Q000096:biosynthesis / Q000187:drug effects; D012093:Replicon / Q000187:drug effects*; D014407:Tumor Cells, Cultured; D014779:Virus Replication / Q000187:drug effects*
D016898:Interferon-alpha; D012367:RNA, Viral