title: Characterization of a hepatitis C virus-like particle vaccine produced in a human hepatocyte-derived cell line.
abstract: An effective immune response against hepatitis C virus (HCV) requires the early development of multi-specific class 1 CD8+ and class II CD4+ T-cells together with broad neutralizing antibody responses. We have produced mammalian-cell-derived HCV virus-like particles (VLPs) incorporating core, E1 and E2 of HCV genotype 1a to produce such immune responses. Here we describe the biochemical and morphological characterization of the HCV VLPs and study HCV core-specific T-cell responses to the particles. The E1 and E2 glycoproteins in HCV VLPs formed non-covalent heterodimers and together with core protein assembled into VLPs with a buoyant density of 1.22 to 1.28 g cm-3. The HCV VLPs could be immunoprecipited with anti-ApoE and anti-ApoC. On electron microscopy, the VLPs had a heterogeneous morphology and ranged in size from 40 to 80 nm. The HCV VLPs demonstrated dose-dependent binding to murine-derived dendritic cells and the entry of HCV VLPs into Huh7 cells was blocked by anti-CD81 antibody. Vaccination of BALB/c mice with HCV VLPs purified from iodixanol gradients resulted in the production of neutralizing antibody responses while vaccination of humanized MHC class I transgenic mice resulted in the prodution of HCV core-specific CD8+ T-cell responses. Furthermore, IgG purified from the sera of patients chronically infected with HCV genotypes 1a and 3a blocked the binding and entry of the HCV VLPs into Huh7 cells. These results show that our mammalian-cell-derived HCV VLPs induce humoral and HCV-specific CD8+ T-cell responses and will have important implications for the development of a preventative vaccine for HCV.
authors.affiliation: Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Earnest-Silveira
authors.affiliation: Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: B
authors.initials: B
authors.lastname: Chua
authors.affiliation: Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Chin
authors.affiliation: Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia.|Department of Surgery, Austin Hospital, University of Melbourne, Australia.
authors.forename: D
authors.initials: D
authors.lastname: Christiansen
authors.affiliation: Department of Infectious Diseases, Austin Hospital, Heidelberg, Victoria 3084, Australia.
authors.forename: D
authors.initials: D
authors.lastname: Johnson
authors.affiliation: Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Herrmann
authors.affiliation: Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Science and Biotechnology, University of Melbourne, Australia.
authors.forename: S A
authors.initials: SA
authors.lastname: Ralph
authors.affiliation: Center for Vaccinology, Ghent University and Hospital, De Pintelaan 185 9000, Ghent, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Vercauteren
authors.affiliation: Center for Vaccinology, Ghent University and Hospital, De Pintelaan 185 9000, Ghent, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Mesalam
authors.affiliation: Center for Vaccinology, Ghent University and Hospital, De Pintelaan 185 9000, Ghent, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Meuleman
authors.affiliation: Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
authors.forename: S
authors.initials: S
authors.lastname: Das
authors.affiliation: Centre for Biomedical Research, Burnet Institute, Melbourne, Australia.
authors.forename: I
authors.initials: I
authors.lastname: Boo
authors.affiliation: Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia.|Centre for Biomedical Research, Burnet Institute, Melbourne, Australia.|Department of Microbiology, Monash University, Clayton, Australia.
authors.forename: H
authors.initials: H
authors.lastname: Drummer
authors.affiliation: Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany.
authors.forename: C-T
authors.initials: CT
authors.lastname: Bock
authors.affiliation: The Basil Hetzel Institute and Queen Elizabeth Hospital, University of Adelaide, Australia.
authors.forename: E J
authors.initials: EJ
authors.lastname: Gowans
authors.affiliation: Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: D C
authors.initials: DC
authors.lastname: Jackson
authors.affiliation: Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: Joseph
authors.initials: J
authors.lastname: Torresi
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D002460:Cell Line; D002478:Cells, Cultured; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology*; D018937:Hepatitis C Antibodies / Q000097:blood*; D022781:Hepatocytes / Q000821:virology; D006801:Humans; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D008854:Microscopy, Electron; D013601:T-Lymphocytes / Q000276:immunology*; D058425:Vaccines, Virus-Like Particle / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D014758:Viral Core Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D022701:Virosomes / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D057134:Antibodies, Neutralizing; C087035:E1 protein, Hepatitis C virus; D018937:Hepatitis C Antibodies; D058425:Vaccines, Virus-Like Particle; D014758:Viral Core Proteins; D014759:Viral Envelope Proteins; D022701:Virosomes; C069130:nucleocapsid protein, Hepatitis C virus; C091015:glycoprotein E2, Hepatitis C virus