To analyze the mechanisms of HCV drug resistance by using chimeric HCV cell culture system

2014 Fiscal Year Final Research Report

• Project/Area Number: 25860513
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Gastroenterology
• Research Institution: Hokkaido University
• Principal Investigator: SUDA Goki 北海道大学, 医学(系)研究科(研究院), 特任助教 (20447460)
• Co-Investigator(Renkei-kenkyūsha): SAKAMOTO Naoya 北海道大学, 大学院医学研究科, 教授 (10334418)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: ＨＣＶ / ＩＦＮ / 薬剤耐性ウイルス

Outline of Final Research Achievements

The mechanism of HCV resistance to IFN has not been wellunderstood. We conducted homologous recombination between HCV-2b and JFH1 and ensured that the chimeric virus could be long-cultured. Then we long-cultured HCV-2b/JFH1 chimeric virus (C3) with or without IFN and compared virus kinetics between the two groups, and tried to extract IFN resistant clone. Supernatant HCV of C3 decreased immediately. However, 6 weeks after IFN treatment, replication of one C3 clone increased . Comparison of amino acid sequences revealed two sequence differences in structure region. Next we constructed these two sequence differences substituted C3 clone (IFNrC3) and compared IFN sensitivity between IFNrC3 and C3 by transfection into cells and subsequently IFN treatment. The newly constructed IFNrC3 showed resistance to IFN.
Additionally, we investigated prevalence of resistant HCV against DAA in japan by using NGS. The existence of resistant virus did not affect treatment outcome in TPV based therapy.

Free Research Field

肝臓病学