title: A synthetic codon-optimized hepatitis C virus nonstructural 5A DNA vaccine primes polyfunctional CD8+ T cell responses in wild-type and NS5A-transgenic mice.
abstract: The hepatitis C virus (HCV) nonstructural (NS) 5A protein has been shown to promote viral persistence by interfering with both innate and adaptive immunity. At the same time, the HCV NS5A protein has been suggested as a target for antiviral therapy. In this study, we performed a detailed characterization of HCV NS5A immunogenicity in wild-type (wt) and immune tolerant HCV NS5A-transgenic (Tg) C57BL/6J mice. We evaluated how efficiently HCV NS5A-based genetic vaccines could activate strong T cell responses. Truncated and full-length wt and synthetic codon-optimized NS5A genotype 1b genes were cloned into eukaryotic expression plasmids, and the immunogenicity was determined after i.m. immunization in combination with in vivo electroporation. The NS5A-based genetic vaccines primed high Ab levels, with IgG titers of >10(4) postimmunization. With respect to CD8(+) T cell responses, the coNS5A gene primed more potent IFN-γ-producing and lytic cytotoxic T cells in wt mice compared with NS5A-Tg mice. In addition, high frequencies of NS5A-specific CD8(+) T cells were found in wt mice after a single immunization. To test the functionality of the CTL responses, the ability to inhibit growth of NS5A-expressing tumor cells in vivo was analyzed after immunization. A single dose of coNS5A primed tumor-inhibiting responses in both wt and NS5A-Tg mice. Finally, immunization with the coNS5A gene primed polyfunctional NS5A-specific CD8(+) T cell responses. Thus, the coNS5A gene is a promising therapeutic vaccine candidate for chronic HCV infections.
authors.affiliation: Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, S-141 86 Stockholm, Sweden.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Holmström
authors.forename: Anna
authors.initials: A
authors.lastname: Pasetto
authors.forename: Veronica
authors.initials: V
authors.lastname: Nähr
authors.forename: Anette
authors.initials: A
authors.lastname: Brass
authors.forename: Malte
authors.initials: M
authors.lastname: Kriegs
authors.forename: Eberhard
authors.initials: E
authors.lastname: Hildt
authors.forename: Kate E
authors.initials: KE
authors.lastname: Broderick
authors.forename: Margaret
authors.initials: M
authors.lastname: Chen
authors.forename: Gustaf
authors.initials: G
authors.lastname: Ahlén
authors.forename: Lars
authors.initials: L
authors.lastname: Frelin
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D019496:Cancer Vaccines; D003062:Codon / Q000235:genetics; D003602:Cytotoxicity, Immunologic; D004279:DNA, Viral / Q000138:chemical synthesis / Q000235:genetics / Q000276:immunology*; D005813:Genes, Synthetic; D006183:H-2 Antigens / Q000276:immunology; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology*; D018937:Hepatitis C Antibodies / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D007114:Immunization; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000378:metabolism; D008228:Lymphoma, Non-Hodgkin / Q000276:immunology / Q000628:therapy; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology; D037182:T-Cell Antigen Receptor Specificity; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D019444:Vaccines, DNA / Q000276:immunology*; D014761:Viral Hepatitis Vaccines / Q000276:immunology* / Q000627:therapeutic use; D017361:Viral Nonstructural Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D012324:RNA-Dependent RNA Polymerase
chemical_list: D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D003062:Codon; D004279:DNA, Viral; D006183:H-2 Antigens; D018937:Hepatitis C Antibodies; D007074:Immunoglobulin G; D008222:Lymphokines; D010446:Peptide Fragments; D019444:Vaccines, DNA; D014761:Viral Hepatitis Vaccines; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase