Elimination of cccDNA by genome editing by using HBV-infected mice

• Project/Area Number: 17K09427
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Gastroenterology
• Research Institution: Hiroshima University
• Principal Investigator: Imamura Michio 広島大学, 病院(医), 講師 (40403513)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2019: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2018: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2017: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
• Keywords: B型肝炎 / cccDNA / ヒト肝細胞移植マウス / 末梢血単核球 / B型肝炎ウイルス / 肝臓学

Outline of Final Research Achievements

High-dose combination therapy with six weeks of entecavir plus PEG-IFN for hepatitis B virus (HBV)-infected human hepatocyte transplanted uPA/SCID mice resulted in persistently negative HBV DNA in serum. Serum HBsAg and hepatitis B corerelated antigen (HBcrAg) continued to decrease and eventually became negative at 12 weeks after cessation of the therapy. Persistent loss of serum HBV DNA and loss of HBV markers by entecavir and PEG-IFN combination treatment in mice suggests that control of HBV can be achieved even in the absence of a cellular immune response. We generated new immunodeficiency cDNA-uPA/Rag2-/-/Jak3-/- mice with humanized livers that were almost completely repopulated with human hepatocytes and succeeded in HBV infection to these mice. Co-culture of PBMCs with human hepatocyte and anti-CD80/CD86 antibodies before administration to mice resulted in an establishment of human CD45-positive mononuclear cell chimerism with reduction of allo-immunity.

Academic Significance and Societal Importance of the Research Achievements

HBV感染マウスに抗ウイルス薬を投与することで肝内cccDNAを十分に低下させることが可能であった。今後、抗ウイルス薬と免疫調整薬を組み合わせることにより肝内cccDNAを消失させる治療法開発が期待される。cDNA-uPA/Rag2-/-/Jak3-/-マウスを用いてヒトPBMCの生着が可能であった。今後さらに生着したPBMCのプロファイルの解析、HBV特異的CTLの有無、肝線維化発症の有無などの検討が必要である。B型肝炎モデルマウスの構築は、B型慢性肝炎に対する根治的治療法開発に有用である。

Research Products

• [Int'l Joint Research] National Institutes of Health(米国)
• [Int'l Joint Research] Loyola University/Liver Diseases Branch, NIH(米国)
• [Journal Article] Diminished hepatic IFN response following HCV clearance triggers HBV reactivation in coinfection. (2020)
  • Author(s): Cheng X, Uchida T, Xia Y, Umarova R, Liu CJ, Chen PJ, Gaggar A, Suri V, Mucke MM, Vermehren J, Zeuzem S, Teraoka Y, Osawa M, Aikata H, Tsuji K, Mori N, Hige S, Karino Y, Imamura M, Chayama K, Liang TJ.
  • Journal Title: J Clin Invest. Volume: - Issue: 6 Pages: 3205-3220
  • DOI: 10.1172/jci135616
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Acute hepatitis B virus infection in humanized chimeric mice has multiphasic viral kinetics (2018)
  • Author(s): Ishida Y, Chung TL, Imamura M, Hiraga N, Sen S, Yokomichi H, Tateno C, Canini L, Perelson AS, Uprichard SL, Dahari H, Chayama K
  • Journal Title: Hepatology Volume: 68 Issue: 2 Pages: 473-484
  • DOI: 10.1002/hep.29891
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Usefulness of humanized cDNA-uPA/SCID mice for the study of hepatitis B virus and hepatitis C virus virology. (2017)
  • Author(s): Uchida T, Imamura M, Kan H, Hiraga N, Hayes CN, Tsuge M, Abe-Chayama H, Aikata H, Makokha GN, Miki D, Ochi H, Ishida Y, Tateno C, Chayama K.
  • Journal Title: J Gen Virol. Volume: 印刷中 Issue: 5 Pages: 1040-1047
  • DOI: 10.1099/jgv.0.000726
  • Peer Reviewed
• [Journal Article] Persistent loss of HBV markers in serum without cellular immunity by combination of PEG-IFN plus ETV therapy in humanized mice (2017)
  • Author(s): Uchida T, Imamura M, Hayes CN, Hiraga N, Kan H, Tsuge M, Abe-Chayama H, Zhang Y, Makokha GN, Aikata H, Miki D, Ochi H, Ishida Y, Tateno C, Chayama K
  • Journal Title: Antimicrob Agents Chemother Volume: 61 Issue: 9
  • DOI: 10.1128/aac.00725-17
  • Peer Reviewed / Open Access
• [Presentation] ヒト肝細胞キメラマウスを用いた肝内cccDNA制御による抗HBV療法 (2017)
  • Author(s): 内田宅郎、今村道雄、茶山一彰
  • Organizer: 第53回日本肝臓学会総会
• [Presentation] Persistent loss of HBV markers in serum without cellular immunity by combination of PEG-IFN plus ETV therapy in humanized mice (2017)
  • Author(s): Takuro Uchida, Michio Imamura, Nelson C Hayes, Nobuhiko Hiraga, Masataka Tsuge, Hiromi Abe-Chayama, Grace Naswa Makokha, Yuji Ishida, Chise Tateno, Kazuaki Chayama
  • Organizer: AASLD The liver meeting 2017
  • Int'l Joint Research