{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T12:49:27Z","timestamp":1788871767381,"version":"build-2803163510"},"reference-count":57,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2015,1,19]],"date-time":"2015-01-19T00:00:00Z","timestamp":1421625600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Research Council of Norway","doi-asserted-by":"publisher","award":["183196"],"award-info":[{"award-number":["183196"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Vaccination is an important strategy for the control and prevention of infectious pancreatic necrosis (IPN) in farmed Atlantic salmon (Salmo salar) in the post-smolt stage in sea-water. In this study, a heterologous gene expression system, based on a replicon  construct of salmonid alphavirus (SAV), was used for in vitro and in vivo expression of IPN virus proteins. The large open reading frame of segment A, encoding the polyprotein  NH2-pVP2-VP4-VP3-COOH, as well as pVP2, were cloned and expressed by the SAV replicon in Chinook salmon embryo cells (CHSE-214) and epithelioma papulosum cyprini (EPC) cells. The replicon constructs pSAV\/polyprotein (pSAV\/PP) and pSAV\/pVP2 were used to immunize Atlantic salmon (Salmo salar) by a single intramuscular injection and tested in a subsequent IPN virus (IPNV) challenge trial. A low to moderate protection against IPN was observed in fish immunized with the replicon vaccine that encoded the pSAV\/PP, while the pSAV\/pVP2 construct was not found to induce protection.<\/jats:p>","DOI":"10.3390\/v7010252","type":"journal-article","created":{"date-parts":[[2015,1,19]],"date-time":"2015-01-19T10:53:54Z","timestamp":1421664834000},"page":"252-267","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["A Polyprotein-Expressing Salmonid Alphavirus Replicon Induces Modest Protection in Atlantic Salmon (Salmo Salar) Against Infectious Pancreatic Necrosis"],"prefix":"10.3390","volume":"7","author":[{"given":"Azila","family":"Abdullah","sequence":"first","affiliation":[{"name":"Department of Food Safety and Infection Biology, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 8146 Dep, 0033 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christel","family":"Olsen","sequence":"additional","affiliation":[{"name":"Department of Food Safety and Infection Biology, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 8146 Dep, 0033 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kjartan","family":"Hodneland","sequence":"additional","affiliation":[{"name":"MSD Animal Health Norway, Thorm\u00f8hlensgate 55, N-5008 Bergen, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9911-5948","authenticated-orcid":false,"given":"Espen","family":"Rimstad","sequence":"additional","affiliation":[{"name":"Department of Food Safety and Infection Biology, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 8146 Dep, 0033 Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/0959-8030(95)00011-9","article-title":"Serological classification of infectious pancreatic necrosis (IPN) virus and other aquatic birnaviruses","volume":"5","author":"Hill","year":"1995","journal-title":"Annu. Rev. Fish Dis."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2061","DOI":"10.1099\/0022-1317-80-8-2061","article-title":"Characteristics of a new birnavirus associated with a warmwater fish cell line","volume":"80","author":"John","year":"1999","journal-title":"J. Gen. Virol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1973","DOI":"10.1099\/vir.0.80438-0","article-title":"An approach for genogrouping of Japanese isolates of aquabirnaviruses in a new genogroup, VII, based on the VP2\/NS junction region","volume":"86","author":"Nishizawa","year":"2005","journal-title":"J. Gen. Virol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1111\/j.1365-2761.1981.tb01117.x","article-title":"A New Viral Epizootic of Anguilla-Japonica Temminck and Schlegel","volume":"4","author":"Sano","year":"1981","journal-title":"J. Fish Dis."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"105","DOI":"10.3181\/00379727-104-25743","article-title":"Virus Nature of Infectious Pancreatic Necrosis in Trout","volume":"104","author":"Wolf","year":"1960","journal-title":"Pr. Soc. Exp. Biol. Med."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1186\/BF03547948","article-title":"Infectious Pancreatic Necrosis-1St Isolation of Virus from Fish in Norway","volume":"17","author":"Hastein","year":"1976","journal-title":"Acta Vet. Scand."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"288","DOI":"10.1177\/104063879000200406","article-title":"Immunohistochemical identification of infectious pancreatic necrosis virus in paraffin-embedded tissues of Atlantic salmon (Salmo salar)","volume":"2","author":"Evensen","year":"1990","journal-title":"J. Vet. Diagn. Invest."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2057","DOI":"10.1128\/JVI.74.5.2057-2066.2000","article-title":"Active residues and viral substrate cleavage sites of the protease of the birnavirus infectious pancreatic necrosis virus","volume":"74","author":"Petit","year":"2000","journal-title":"J. Virol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/0959-8030(95)00003-8","article-title":"The molecular biology of infectious pancreatic necrosis virus","volume":"5","author":"Dobos","year":"1995","journal-title":"Annu. Rev. Fish Dis."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"13829","DOI":"10.1128\/JVI.78.24.13829-13838.2004","article-title":"Genome assembly and particle maturation of the birnavirus infectious pancreatic necrosis virus","volume":"78","author":"Villanueva","year":"2004","journal-title":"J. Virol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"5110","DOI":"10.1016\/j.vaccine.2012.05.062","article-title":"Evaluation of the immune response against immature viral particles of infectious pancreatic necrosis virus (IPNV): A new model to develop an attenuated vaccine","volume":"30","author":"Galaz","year":"2012","journal-title":"Vaccine"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.virol.2003.12.016","article-title":"Identification of putative motifs involved in the virulence of infectious pancreatic necrosis virus","volume":"322","author":"Santi","year":"2004","journal-title":"Virology"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3229","DOI":"10.1128\/JVI.02939-12","article-title":"Structure of a VP1-VP3 Complex Suggests How Birnaviruses Package the VP1 Polymerase","volume":"87","author":"Bahar","year":"2013","journal-title":"J. Virol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"6652","DOI":"10.1128\/JVI.02831-06","article-title":"VP3, a structural protein of infectious pancreatic necrosis virus, interacts with RNA-dependent RNA polymerase VP1 and with double-stranded RNA","volume":"81","author":"Pedersen","year":"2007","journal-title":"J. Virol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1103","DOI":"10.1007\/s00705-007-0935-z","article-title":"Characterization of cleavage sites and protease activity in the polyprotein precursor of Japanese marine aquabirnavirus and expression analysis of generated proteins by a VP4 protease activity in four distinct cell lines","volume":"152","author":"Imajoh","year":"2007","journal-title":"Arch. Virol."},{"key":"ref_16","first-page":"2059","article-title":"Comparison of the immunogenicity of recombinant VP2 and VP3 of infectious pancreatic necrosis virus and marine birnavirus","volume":"149","author":"Moon","year":"2004","journal-title":"Arch. Virol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1016\/j.fsi.2012.01.004","article-title":"Slow release cortisol implants result in impaired innate immune responses and higher infection prevalence following experimental challenge with infectious pancreatic necrosis virus in Atlantic salmon (Salmo salar) parr","volume":"32","author":"Gadan","year":"2012","journal-title":"Fish Shellfish Immun."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1111\/j.1365-2761.2006.00758.x","article-title":"Analysis of the incidence of infectious pancreatic necrosis mortality in pedigreed Atlantic salmon, Salmo salar L., populations","volume":"29","author":"Guy","year":"2006","journal-title":"J. Fish Dis."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1016\/j.aquaculture.2007.03.021","article-title":"Mortality after IPNV challenge of Atlantic salmon (Salmo salar L.) differs based on developmental stage of fish or challenge route","volume":"271","author":"Ronneseth","year":"2007","journal-title":"Aquaculture"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1006\/fsim.1997.0113","article-title":"Vaccination of Atlantic salmon with recombinant VP2 of infectious pancreatic necrosis virus (IPNV), added to a multivalent vaccine, suppresses viral replication following IPNV challenge","volume":"7","author":"Frost","year":"1997","journal-title":"Fish Shellfish Immun."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2657","DOI":"10.1016\/j.vaccine.2011.01.097","article-title":"A comparative review on European-farmed finfish RNA viruses and their vaccines","volume":"29","author":"Estepa","year":"2011","journal-title":"Vaccine"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1016\/0165-2427(86)90142-X","article-title":"Experimental Induction of the Carrier State in Yearling Brook Trout-A Model Challenge Protocol for Ipnv Immunization","volume":"12","author":"Bootland","year":"1986","journal-title":"Vet. Immun. Immunopathol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"11","DOI":"10.3354\/dao060011","article-title":"Protection of Atlantic salmon Salmo salar against infectious pancreatic necrosis after DNA vaccination","volume":"60","author":"Mikalsen","year":"2004","journal-title":"Dis. Aquatic. Org."},{"key":"ref_24","first-page":"460","article-title":"Efficacy of a recombinant vaccine against infectious pancreatic necrosis in Atlantic salmon post-smolt","volume":"90","author":"Frost","year":"1997","journal-title":"Fish Vaccinol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"723","DOI":"10.1111\/j.1365-2761.2007.00858.x","article-title":"Field validation of experimental challenge models for IPN vaccines","volume":"30","author":"Ramstad","year":"2007","journal-title":"J. Fish Dis."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"4007","DOI":"10.1016\/j.vaccine.2012.04.039","article-title":"Comparison of vaccine efficacy for different antigen delivery systems for infectious pancreatic necrosis virus vaccines in Atlantic salmon (Salmo salar L.) in a cohabitation challenge model","volume":"30","author":"Fredriksen","year":"2012","journal-title":"Vaccine"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1002\/rmv.360","article-title":"Alphavirus vectors and vaccination","volume":"12","author":"Rayner","year":"2002","journal-title":"Rev. Med. Virol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"11371","DOI":"10.1073\/pnas.93.21.11371","article-title":"Alphavirus-based expression vectors: Strategies and applications","volume":"93","author":"Frolov","year":"1996","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"10394","DOI":"10.1128\/JVI.77.19.10394-10403.2003","article-title":"An alphavirus replicon particle chimera derived from Venezuelan equine encephalitis and Sindbis viruses is a potent gene-based vaccine delivery vector","volume":"77","author":"Perri","year":"2003","journal-title":"J. Virol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1016\/j.vaccine.2009.10.015","article-title":"Alphavirus replicon particle vaccines developed for use in humans induce high levels of antibodies to influenza virus hemagglutinin in swine: Proof of concept","volume":"28","author":"Erdman","year":"2010","journal-title":"Vaccine"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"5672","DOI":"10.1016\/j.vaccine.2013.09.058","article-title":"Salmonid alphavirus replicon is functional in fish, mammalian and insect cells and in vivo in shrimps (Litopenaeus vannamei)","volume":"31","author":"Olsen","year":"2013","journal-title":"Vaccine"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1186\/1743-422X-6-173","article-title":"Characterization of untranslated regions of the salmonid alphavirus 3 (SAV3) genome and construction of a SAV3 based replicon","volume":"6","author":"Karlsen","year":"2009","journal-title":"Virol. J."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1186\/1756-0500-3-241","article-title":"Development of infectious cDNA clones of Salmonid alphavirus subtype 3","volume":"3","author":"Karlsen","year":"2010","journal-title":"BMC Res. Notes"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"6206","DOI":"10.1016\/j.vaccine.2014.09.026","article-title":"Salmonid alphavirus glycoprotein E2 requires low temperature and E1 for virion formation and induction of protective immunity","volume":"32","author":"Hikke","year":"2014","journal-title":"Vaccine"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1016\/j.vaccine.2012.11.045","article-title":"A hemagglutinin-esterase-expressing salmonid alphavirus replicon protects Atlantic salmon (Salmo salar) against infectious salmon anemia (ISA)","volume":"31","author":"Wolf","year":"2013","journal-title":"Vaccine"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1016\/0378-1135(90)90151-K","article-title":"Detection of infectious pancreatic necrosis virus (IPNV) RNA by hybridization with an oligonucleotide DNA probe","volume":"23","author":"Rimstad","year":"1990","journal-title":"Vet. Microbiol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.virusres.2013.07.001","article-title":"Infectious salmon anaemia virus nuclear export protein is encoded by a spliced gene product of genomic segment 7","volume":"177","author":"Ramly","year":"2013","journal-title":"Virus Res."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"701","DOI":"10.1111\/j.1365-2761.2010.01165.x","article-title":"Current lineages of the epithelioma papulosum cyprini (EPC) cell line are contaminated with fathead minnow, Pimephales promelas, cells","volume":"33","author":"Winton","year":"2010","journal-title":"J. Fish Dis."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"25","DOI":"10.3354\/dao022025","article-title":"Isolation of A Toga-Like Virus from Farmed Atlantic Salmon Salmo-Salar with Pancreas Disease","volume":"22","author":"Nelson","year":"1995","journal-title":"Dis. Aquatic Org."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"653","DOI":"10.1007\/s10495-010-0468-x","article-title":"Aquatic birnavirus capsid protein, VP3, induces apoptosis via the Bad-mediated mitochondria pathway in fish and mouse cells","volume":"15","author":"Chiu","year":"2010","journal-title":"Apoptosis"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"8903","DOI":"10.1128\/JVI.00851-10","article-title":"Alpha Interferon and Not Gamma Interferon Inhibits Salmonid Alphavirus Subtype 3 Replication In Vitro","volume":"84","author":"Xu","year":"2010","journal-title":"J. Virol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"120","DOI":"10.1016\/j.fsi.2008.11.021","article-title":"In vitro and in vivo immune responses induced by a DNA vaccine encoding the VP2 gene of the infectious pancreatic necrosis virus","volume":"27","author":"Prieto","year":"2009","journal-title":"Fish Shellfish Immun."},{"key":"ref_43","first-page":"165","article-title":"Development of a subunit vaccine for infectious pancreatic necrosis virus using a baculovirus insect\/larvae system","volume":"121","author":"Shivappa","year":"2005","journal-title":"Dev. Biol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1046\/j.1365-2761.2002.00402.x","article-title":"Development of a reproducible infectious pancreatic necrosis virus challenge model for Atlantic salmon, Salmo salar L.","volume":"25","author":"Bowden","year":"2002","journal-title":"J. Fish Dis."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"3291","DOI":"10.1016\/j.vaccine.2010.02.106","article-title":"An active DNA vaccine against infectious pancreatic necrosis virus (IPNV) with a different mode of action than fish rhabdovirus DNA vaccines","volume":"28","author":"Cuesta","year":"2010","journal-title":"Vaccine"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"2193","DOI":"10.1099\/0022-1317-67-10-2193","article-title":"Monoclonal-Antibodies to Infectious Pancreatic Necrosis Virus-Analysis of Viral Epitopes and Comparison of Different Isolates","volume":"67","author":"Caswellreno","year":"1986","journal-title":"J. Gen. Virol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1111\/j.1365-2761.1990.tb00789.x","article-title":"Infectious Pancreatic Necrosis Virus in Norway-Partial Serotyping by Monoclonal-Antibodies","volume":"13","author":"Christie","year":"1990","journal-title":"J. Fish Dis."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1165","DOI":"10.1099\/0022-1317-76-5-1165","article-title":"Mapping of Neutralization Epitopes on Infectious Pancreatic Necrosis Viruses","volume":"76","author":"Frost","year":"1995","journal-title":"J. Gen. Virol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1099\/0022-1317-76-3-551","article-title":"Evidence of A Major Neutralizable Conformational Epitope Region on Vp2 of Infectious Pancreatic Necrosis Virus","volume":"76","author":"Tarrab","year":"1995","journal-title":"J. Gen. Virol."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1792","DOI":"10.1128\/JVI.01536-09","article-title":"Crystal Structure of an Aquabirnavirus Particle: Insights into Antigenic Diversity and Virulence Determinism","volume":"84","author":"Coulibaly","year":"2010","journal-title":"J. Virol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"10289","DOI":"10.1128\/JVI.79.16.10289-10299.2005","article-title":"Molecular determinants of infectious pancreatic necrosis virus virulence and cell culture adaptation","volume":"79","author":"Song","year":"2005","journal-title":"J. Virol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"220","DOI":"10.1016\/j.fsi.2014.02.003","article-title":"Food pellets as an effective delivery method for a DNA vaccine against infectious pancreatic necrosis virus in rainbow trout (Oncorhynchus mykiss, Walbaum)","volume":"37","author":"Ballesteros","year":"2014","journal-title":"Fish Shellfish Immun."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.virol.2004.01.025","article-title":"The C-terminal domain of the pVP2 precursor is essential for the interaction between VP2 and VP3, the capsid polypeptides of infectious bursal disease virus","volume":"322","author":"Ona","year":"2004","journal-title":"Virology"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"4082","DOI":"10.1128\/JVI.06535-11","article-title":"Superior Induction of T Cell Responses to Conserved HIV-1 Regions by Electroporated Alphavirus Replicon DNA Compared to That with Conventional Plasmid DNA Vaccine","volume":"86","author":"Knudsen","year":"2012","journal-title":"J. Virol."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1281","DOI":"10.1007\/s00705-010-0717-x","article-title":"The amino terminus of the salmonid alphavirus capsid protein determines subcellular localization and inhibits cellular proliferation","volume":"155","author":"Karlsen","year":"2010","journal-title":"Arch. Virol."},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Moen, T., Baranski, M., Sonesson, A.K., and Kjoglum, S. (2009). Confirmation and fine-mapping of a major QTL for resistance to infectious pancreatic necrosis in Atlantic salmon (Salmo salar): Population-level associations between markers and trait. BMC Genomics, 10.","DOI":"10.1186\/1471-2164-10-368"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"531","DOI":"10.1111\/j.1365-2052.2010.02032.x","article-title":"Segregation of infectious pancreatic necrosis resistance QTL in the early life cycle of Atlantic Salmon (Salmo salar)","volume":"41","author":"Gheyas","year":"2010","journal-title":"Anim. Genet."}],"container-title":["Viruses"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1999-4915\/7\/1\/252\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:41:45Z","timestamp":1760215305000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1999-4915\/7\/1\/252"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,1,19]]},"references-count":57,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2015,1]]}},"alternative-id":["v7010252"],"URL":"https:\/\/doi.org\/10.3390\/v7010252","relation":{},"ISSN":["1999-4915"],"issn-type":[{"value":"1999-4915","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,1,19]]}}}