{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T14:00:39Z","timestamp":1789826439540,"version":"4.0.1"},"reference-count":41,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2018,8,30]],"date-time":"2018-08-30T00:00:00Z","timestamp":1535587200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Base on the sequence of S genes, which encode spike proteins, we previously identified three different types (North American, S INDEL, and S large-DEL types) of porcine epidemic diarrhea virus (PEDV) that have re-emerged in Japan since 2013. Based on experimental infections with the North American and S large-DEL types, we also hypothesized that PEDV virulence may be linked to the S1 subunit of the S protein. To test this hypothesis, we have now assayed in gnotobiotic piglets various recombinant PEDVs generated by reverse genetics. Piglets inoculated with CV777 maintained in National Institute of Animal Health, along with piglets infected with a recombinant form of the same virus, developed subclinical to mild diarrhea. In contrast, severe watery diarrhea, dehydration, weight loss, astasia, and high mortality were observed in piglets inoculated with recombinant strains in which the S gene was partially or fully replaced with corresponding sequences from the highly virulent Japanese PEDV isolate OKN-1\/JPN\/2013. Indeed, symptoms resembled those in piglets inoculated with the OKN-1\/JPN\/2013, and were especially pronounced in younger piglets. Collectively, the data demonstrate that the S1 subunit of the S protein is an important determinant of PEDV virulence, and advance development of new vaccine candidate.<\/jats:p>","DOI":"10.3390\/v10090467","type":"journal-article","created":{"date-parts":[[2018,8,30]],"date-time":"2018-08-30T10:30:06Z","timestamp":1535625006000},"page":"467","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["S1 Subunit of Spike Protein from a Current Highly Virulent Porcine Epidemic Diarrhea Virus Is an Important Determinant of Virulence in Piglets"],"prefix":"10.3390","volume":"10","author":[{"given":"Tohru","family":"Suzuki","sequence":"first","affiliation":[{"name":"Division of Viral Disease and Epidemiology, National Institute of Animal Health, National Agricultural Research Organization, Tsukuba, Ibaraki 3050856, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yutaka","family":"Terada","sequence":"additional","affiliation":[{"name":"Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Enjuanes","sequence":"additional","affiliation":[{"name":"Department of Molecular and Cell Biology, Centro Nacional de Biotecnologia, Campus Universidad Aut\u00f3noma de Madrid, 28049 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seiichi","family":"Ohashi","sequence":"additional","affiliation":[{"name":"Division of Viral Disease and Epidemiology, National Institute of Animal Health, National Agricultural Research Organization, Tsukuba, Ibaraki 3050856, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wataru","family":"Kamitani","sequence":"additional","affiliation":[{"name":"Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1007\/BF01317606","article-title":"A new coronavirus-like particle associated with diarrhea in swine","volume":"58","author":"Pensaert","year":"1978","journal-title":"Arch. Virol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1136\/vr.100.12.243","article-title":"An apparently new syndrome of porcine epidemic diarrhea","volume":"100","author":"Wood","year":"1977","journal-title":"Vet. Rec."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/S0034-5288(18)32994-1","article-title":"Virus-like particles associated with porcine epidemic diarrhoea","volume":"25","author":"Chasey","year":"1978","journal-title":"Res. Vet. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"829","DOI":"10.1292\/jvms1939.45.829","article-title":"An outbreak of swine diarrhea of a new-type associated with coronavirus-like particles in Japan","volume":"45","author":"Takahashi","year":"1983","journal-title":"Jpn. J. Vet. Sci."},{"key":"ref_5","first-page":"249","article-title":"Isolation of porcine epidemic diarrhea virus (PEDV) in Korea","volume":"33","author":"Kweon","year":"1993","journal-title":"Korean J. Vet. Res."},{"key":"ref_6","first-page":"594","article-title":"Prevalence of infectious with enzootic respiratory and enteric viruses in feeder pigs entering fattening herds","volume":"135","author":"Pensaert","year":"1994","journal-title":"Vet. Rec."},{"key":"ref_7","first-page":"9","article-title":"Enterotoxigenic Escherichia coli, rotavirus, porcine epidemic diarrhoea virus, adenovirus and calici-like virus in porcine postweaning diarrhoea in Hungary","volume":"44","author":"Nagy","year":"1996","journal-title":"Acta Vet. Hung."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1007\/s11262-012-0713-1","article-title":"Porcine epidemic diarrhoea virus: A comprehensive review of molecular epidemiology, diagnosis and vaccine","volume":"44","author":"Song","year":"2012","journal-title":"Virus Genes"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1471","DOI":"10.1007\/s00705-010-0720-2","article-title":"Molecular epidemiology of porcine epidemic diarrhea virus in China","volume":"155","author":"Chen","year":"2010","journal-title":"Arch. Virol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"499","DOI":"10.1007\/s11262-012-0794-x","article-title":"Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) samples from field cases in Fujian, China","volume":"45","author":"Chen","year":"2012","journal-title":"Virus Genes"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1350","DOI":"10.3201\/eid1803.120002","article-title":"New variants of porcine epidemic diarrhea virus, China, 2011","volume":"18","author":"Li","year":"2012","journal-title":"Emerg. Infect. Dis."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1007\/s11262-012-0735-8","article-title":"Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea virus (PEDV) field cases in south China","volume":"45","author":"Li","year":"2012","journal-title":"Virus Genes"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e00737-13","DOI":"10.1128\/mBio.00737-13","article-title":"Origin, evolution, and genotyping of emergent porcine epidemic diarrhea virus strains in the United States","volume":"4","author":"Huang","year":"2013","journal-title":"MBio"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"649","DOI":"10.1177\/1040638713501675","article-title":"Emergence of porcine epidemic diarrhea virus in the United States: Clinical signs, lesions, and viral genomic sequences","volume":"25","author":"Stevenson","year":"2013","journal-title":"J. Vet. Diagn. Investig."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"917","DOI":"10.3201\/eid2005.140195","article-title":"New variant of porcine epidemic diarrhea virus, United States, 2014","volume":"20","author":"Wang","year":"2014","journal-title":"Emerg. Infect. Dis."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1620","DOI":"10.3201\/eid2010.140491","article-title":"Distinct characteristics and complex evolution of PEDV strains, North America, May 2013\u2013February 2014","volume":"20","author":"Vlasova","year":"2014","journal-title":"Emerg. Infect. Dis."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1111\/tbed.12269","article-title":"Investigation into the role of potentially contaminated feed as a source of the first-detected outbreaks of porcine epidemic diarrhea in Canada","volume":"61","author":"Pasick","year":"2014","journal-title":"Transbound. Emerg. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1223","DOI":"10.3201\/eid2007.140294","article-title":"Outbreak-related porcine epidemic diarrhea virus strains similar to US strains, South Korea, 2013","volume":"20","author":"Lee","year":"2014","journal-title":"Emerg. Infect. Dis."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1016\/j.meegid.2014.06.005","article-title":"Comparative genome analysis and molecular epidemiclogy of the reemerging porcine epidemic diarrhea virus strains isolated in Korea","volume":"26","author":"Choi","year":"2014","journal-title":"Infect. Genet. Evol."},{"key":"ref_20","first-page":"2","article-title":"Molecular characterization of the porcine epidemic diarrhea virus TW4\/2014 in Taiwan","volume":"1","author":"Chiou","year":"2014","journal-title":"Austin Virol. Retrovirol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4893","DOI":"10.3201\/eid2103.141165","article-title":"Comparison of porcine epidemic diarrhea viruses from Germany and the United States, 2014","volume":"21","author":"Hanke","year":"2015","journal-title":"Emerg. Infect. Dis."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"e00506-15","DOI":"10.1128\/genomeA.00506-15","article-title":"Complete genome sequence of a porcine epidemic diarrhea virus from a novel outbreak in Belgium, January 2015","volume":"3","author":"Theuns","year":"2015","journal-title":"Genome Announc."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"e00877-15","DOI":"10.1128\/genomeA.00877-15","article-title":"Complete genome sequence of the porcine epidemic diarrhoea virus variant Tottori2\/JPN\/2014","volume":"3","author":"Murakami","year":"2015","journal-title":"Genome Announc."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1016\/j.meegid.2015.10.017","article-title":"Molecular characterization of pig epidemic diarrhoea viruses isolated in Japan from 2013 to 2014","volume":"36","author":"Suzuki","year":"2015","journal-title":"Infect. Genet. Evol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2565","DOI":"10.1007\/s00705-015-2522-z","article-title":"Discovery of a new PEDV variant with a large deletion in the spike gene identified in domestic pigs","volume":"160","author":"Masuda","year":"2015","journal-title":"Arch. Virol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1823","DOI":"10.1099\/jgv.0.000513","article-title":"Pig epidemic diarrhoea virus S gene variant with a large deletion non-lethal to colostrum-deprived newborn piglet","volume":"97","author":"Suzuki","year":"2016","journal-title":"J. Gen. Virol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"6078","DOI":"10.1128\/JVI.00074-08","article-title":"Cleavage of group 1 coronavirus spike proteins: How furin cleavage is traded off against heparan sulfate binding upon cell culture adaptation","volume":"82","author":"Haijema","year":"2008","journal-title":"J. Virol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"6121","DOI":"10.1128\/JVI.00430-15","article-title":"Receptor usage and cell entry of porcine epidemic diarrhea coronavirus","volume":"89","author":"Liu","year":"2015","journal-title":"J. Virol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1725","DOI":"10.1099\/0022-1317-69-7-1725","article-title":"Antigenic differentiation between transmissible gastroenteritis virus of swine and a related porcine respiratory coronavirus","volume":"69","author":"Callebaut","year":"1988","journal-title":"J. Gen. Virol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1006\/viro.2000.0757","article-title":"Coronavirus spike proteins in viral entry and pathogenesis","volume":"279","author":"Gallagher","year":"2001","journal-title":"Virology"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/bs.aivir.2016.08.004","article-title":"Coronavirus spike protein and tropism changes","volume":"96","author":"Hulswit","year":"2016","journal-title":"Adv. Virus Res."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"e00227-17","DOI":"10.1128\/JVI.00227-17","article-title":"Deletion of a 197-amino-acid region in the N-terminal domain of spike protein attenuates porcine epidemic diarrhea virus in piglets","volume":"91","author":"Hou","year":"2017","journal-title":"J. Virol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e00603-18","DOI":"10.1128\/JVI.00603-18","article-title":"The S is necessary but not sufficient for the virulence of porcine epidemic diarrhea virus novel variant strain BC2011C","volume":"92","author":"Wang","year":"2018","journal-title":"J. Virol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1016\/j.virusres.2014.05.026","article-title":"Coronavirus reverse genetic systems; infectious clones and replicons","volume":"189","author":"Sola","year":"2014","journal-title":"Virus Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"16157","DOI":"10.1073\/pnas.1311542110","article-title":"Reverse genetics with a full-length infectious cDNA of the Middle East respiratory syndrome coronavirus","volume":"110","author":"Scobey","year":"2013","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"10900","DOI":"10.1128\/JVI.00385-06","article-title":"Construction of a severe acute respiratory syndrome coronavirus infectious cDNA clone and a replicon to study coronavirus RNA synthesis","volume":"80","author":"Dediego","year":"2006","journal-title":"J. Virol."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Rasmussen, T.B., Boniotti, M.B., Papetti, A., Papetti, A., Grasland, B., Frossard, J., Dastjerdi, A., Hulst, M., Hanke, D., and Pohlmann, A. (2018). Full-length genome sequences of porcine epidemic diarrhoea virus strain CV777; Use of NGS to analyse genomic and sub-genomic RNAs. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0193682"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.virusres.2016.05.030","article-title":"Porcine epidemic diarrhea: A retrospect from Europe and matters of debate","volume":"226","author":"Pensaert","year":"2016","journal-title":"Virus Res."},{"key":"ref_39","first-page":"28","article-title":"Efficacy of a transmissible gastroenteritis coronavirus with an altered ORF-3 gene","volume":"65","author":"Wood","year":"2001","journal-title":"Can. J. Vet. Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1833","DOI":"10.1016\/S0264-410X(03)00027-6","article-title":"Differentiation of a Vero cell adapted porcine epidemic diarrhea virus from Korean field strains by restriction fragment length polymorphism analysis of ORF3","volume":"21","author":"Song","year":"2003","journal-title":"Vaccine"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1007\/s11262-007-0164-2","article-title":"Cloning and further sequence analysis of the ORF3 gene of wild- and attenuated-type porcine epidemic diarrhea viruses","volume":"36","author":"Park","year":"2008","journal-title":"Virus Genes"}],"container-title":["Viruses"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1999-4915\/10\/9\/467\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:22:11Z","timestamp":1760196131000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1999-4915\/10\/9\/467"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,8,30]]},"references-count":41,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2018,9]]}},"alternative-id":["v10090467"],"URL":"https:\/\/doi.org\/10.3390\/v10090467","relation":{"has-preprint":[{"id-type":"doi","id":"10.20944\/preprints201808.0529.v1","asserted-by":"object"}]},"ISSN":["1999-4915"],"issn-type":[{"value":"1999-4915","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,8,30]]}}}