Characterization of IL-21-expressing recombinant hepatitis B virus (HBV) as a therapeutic agent targeting persisting HBV infection

Zhongliang Shen; Jingwen Wu; Zixiang Gao; Jingyu Wang; Haoxiang Zhu; Richen Mao; Xuanyi Wang; Jiming Zhang; Youhua Xie; Jing Liu

doi:10.7150/thno.44715

Characterization of IL-21-expressing recombinant hepatitis B virus (HBV) as a therapeutic agent targeting persisting HBV infection

Theranostics. 2020 Apr 25;10(12):5600-5612. doi: 10.7150/thno.44715. eCollection 2020.

Authors

Zhongliang Shen^{1

2}, Jingwen Wu¹, Zixiang Gao², Jingyu Wang¹, Haoxiang Zhu¹, Richen Mao¹, Xuanyi Wang^{2

3}, Jiming Zhang^{1

2}, Youhua Xie², Jing Liu^{2

3}

Affiliations

¹ Department of Infectious Diseases, Huashan Hospital, Fudan University, Shanghai 200040, People's Republic of China.
² Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Department of Microbiology and Parasitology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, People's Republic of China.
³ Key Laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, People's Republic of China.

Abstract

Chronic infection by hepatitis B virus (HBV) is associated with high risks of liver fibrosis, cirrhosis and hepatocellular carcinoma. In mouse models of HBV persistence, interleukin 21 (IL-21) has been identified as a potent inducer of viral clearance. Strict hepatotropism makes recombinant HBV (rHBV) vectors ideal for liver-targeting gene delivery. Previously, we established an rHBV vector termed 5c3c, which is highly replicative by itself, but requires HBV envelope proteins provided in trans to produce virions. 5c3c-based rHBV virions are capable of delivering cargo gene expression driven by HBV Sp1 promoter into infected hepatocytes. In this work, we explore the feasibility of using 5c3c-derived rHBV for liver-specific delivery of IL-21 as treatment of chronic HBV infection. Methods: 5c3c-derived rHBV replicons harboring mouse or human IL-21 genes (termed 5c3c-mIL-21 and 5c3c-hIL-21 respectively) were constructed and then tested for the production of rHBV virions in vitro and in vivo. 5c3c-mIL-21's anti-HBV effects were determined in chronic HBV mouse model. Furthermore, superinfection by rHBV virions was analysed using HBV-infected HepG2/NTCP cells and human liver chimeric mice. Results: 5c3c-mIL-21 and 5c3c-hIL-21 were efficiently replicative and produced enveloped virions when provided with envelope proteins, both in vitro and in vivo. In mouse model of HBV persistence, IL-21 expressed from injected 5c3c-mIL-21 replicon induced complete viral clearance. 5c3c-mIL-21 and 5c3c-hIL-21 virions could infect HepG2/NTCP cells and engender sustained IL-21 expression. Most importantly, IL-21-expressing rHBV virions could superinfect HBV-infected HepG2/NTCP cells and human hepatocytes in human liver chimeric mice, and engender sustained IL-21 expression and rHBV production. Conclusion: These data suggest the high potential of 5c3c-derived IL-21-expressing rHBV as a novel therapeutic against chronic HBV infection.

Keywords: HBV clearance; hepatitis B virus; interleukin 21; recombinant HBV vector; superinfection.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
DNA, Viral / genetics
Disease Models, Animal
Genetic Vectors / administration & dosage*
Hepatitis / genetics
Hepatitis / pathology
Hepatitis / therapy*
Hepatitis / virology
Hepatitis B virus / genetics
Hepatitis B virus / isolation & purification*
Humans
Interleukins / administration & dosage*
Interleukins / genetics
Interleukins / metabolism
Male
Mice
Mice, Inbred BALB C

Substances

DNA, Viral
Interleukins
interleukin-21