title: Intracellular-delivery of a single-chain antibody against hepatitis             B core protein via cell-penetrating peptide inhibits hepatitis B virus replication             in vitro.
abstract: Assembly of nucleocapsids is an attractive target for novel anti-hepatitis B virus (HBV) agents, and intracellular single-chain variable fragment (scFv) antibodies against HBV core (HBc) protein are a class of potential alternatives for this purpose; however, their application is limited by the lack of a suitable means of delivery. Owing to the favorable performance of cytoplasmic transduction peptide (CTP) in cargo delivery in hepatocytes, we purified an anti-HBc scFv fused to CTP using a previous screened sequence by a prokaryotic expression system and evaluated its efficacy in the inhibition of HBV in vitro. Our results showed that cytoplasmic translocation of the previous anti-HBc scFv was achieved by CTP in HepG2.2.15 cells. Immunoprecipitation analysis indicated the fusion protein anti-HBc scFv-CTP interacted with its target antigen HBc, and negligible cytotoxicity was observed. Moreover, the anti-HBc scFv-CTP interfered with nucleocapsid assembly and markedly reduced both the supernatant HBV DNA level and the intracellular DNA replication intermediates, with a 5.1 µM of half maximal effect concentration and a dose-dependent effect. In conclusion, this novel anti-HBc scFv fused to CTP demonstrated inhibitory activity of HBV replication in vitro and warrants further in vivo study.
authors.affiliation: Department of Infectious Disease, The Sixth People's Hospital                     Affiliated to Shanghai Jiao Tong University, Shanghai, P.R. China.
authors.forename: Yunhao
authors.initials: Y
authors.lastname: Xun
authors.forename: Qingchun
authors.initials: Q
authors.lastname: Pan
authors.forename: Zhenghao
authors.initials: Z
authors.lastname: Tang
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Chen
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Yu
authors.forename: Min
authors.initials: M
authors.lastname: Xi
authors.forename: Guoqing
authors.initials: G
authors.lastname: Zang
mesh_terms: D000998:Antiviral Agents / Q000008:administration & dosage* / Q000378:metabolism / Q000493:pharmacokinetics / Q000494:pharmacology; D057846:Cell-Penetrating Peptides / Q000008:administration & dosage* / Q000235:genetics / Q000493:pharmacokinetics / Q000494:pharmacology; D056945:Hep G2 Cells; D006509:Hepatitis B / Q000188:drug therapy* / Q000821:virology; D006510:Hepatitis B Antibodies / Q000008:administration & dosage* / Q000494:pharmacology; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D006515:Hepatitis B virus / Q000187:drug effects* / Q000276:immunology / Q000502:physiology; D006801:Humans; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage / Q000235:genetics / Q000493:pharmacokinetics / Q000494:pharmacology; D057127:Single-Chain Antibodies / Q000008:administration & dosage* / Q000235:genetics / Q000493:pharmacokinetics / Q000494:pharmacology; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D057846:Cell-Penetrating Peptides; D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D011993:Recombinant Fusion Proteins; D057127:Single-Chain Antibodies