{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T20:18:13Z","timestamp":1783973893493,"version":"3.55.0"},"reference-count":68,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,14]],"date-time":"2021-01-14T00:00:00Z","timestamp":1610582400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31660717"],"award-info":[{"award-number":["31660717"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31560706"],"award-info":[{"award-number":["31560706"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Guangxi Special Funding on Science and Technology Research","award":["AA17204057"],"award-info":[{"award-number":["AA17204057"]}]},{"name":"Guangxi Program for Modern Agricultural Industry Technical System Construction-Chicken Industry","award":["nycytxgxcxtd-19-03"],"award-info":[{"award-number":["nycytxgxcxtd-19-03"]}]},{"DOI":"10.13039\/501100004607","name":"Natural Science Foundation of Guangxi Province","doi-asserted-by":"publisher","award":["2017GXNSFAA198033"],"award-info":[{"award-number":["2017GXNSFAA198033"]}],"id":[{"id":"10.13039\/501100004607","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004607","name":"Natural Science Foundation of Guangxi Province","doi-asserted-by":"publisher","award":["2014GXNSFDA118018"],"award-info":[{"award-number":["2014GXNSFDA118018"]}],"id":[{"id":"10.13039\/501100004607","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Infectious Bursal Disease Virus (IBDV) has haunted the poultry industry with severe, prolonged immunosuppression of chickens when infected at an early age and can easily lead to other secondary infections. Understanding the pathogenic mechanisms could lead to effective prevention and control of Infectious Bursal Disease (IBD). Evidence suggests that the N-terminal domain of polymerase in segment B plays an important role, but it is not clear which part or residual is crucial for the pathogenicity. Using a reverse genetics technique, a molecular clone (rNN1172) of the parental vvIBDV strain NN1172 was generated, and its pathogenicity was found to be the same as the parental virus. Then, three recombinant chimeric viruses were rescued based on the rNN1172 and substituted with the counterparts in the N-terminal domain of the attenuated vaccine strain B87: the rNN1172-B87VP1a (substituting the full region of the 1\u2013167 aa residuals), the rNN1172-B87VP1a\u22064 (substituting the region of the 5\u2013167 aa residuals), and the rNN1172-VP1\u22064 (one single aa residual substitution V4I), to better explore the role of the N-terminal domain of polymerase on the viral pathogenicity. Interestingly, all these substitutions played different roles in the viral pathogenicity: the mortality of the rNN1172-B87VP1a-challenged chickens was significantly reduced from 30% to 0%. No obvious lesion was found in the histopathological examination, and the lowest viral genome copy number was also detected in the bursa when compared to the parental and two other recombinant viruses. The mortalities caused by rNN1172-B87VP1a\u22064 and rNN1172-B87VP1\u22064, respectively, were all reduced to 10% and had a delayed onset of death. Our results also revealed that the pathogenicity of the IBDV was consistent with the viral replication efficiency in vivo (bursae). This study demonstrated that the full region of the N-terminal of polymerase plays an important role in viral replication and pathogenicity, but the substitutions of its partial region or a single residual do not completely lead to the virus attenuation to Three-Yellow chickens, although that significantly reduces its pathogenicity.<\/jats:p>","DOI":"10.3390\/v13010107","type":"journal-article","created":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T01:33:29Z","timestamp":1610674409000},"page":"107","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["The Full Region of N-Terminal in Polymerase of IBDV Plays an Important Role in Viral Replication and Pathogenicity: Either Partial Region or Single Amino Acid V4I Substitution Does Not Completely Lead to the Virus Attenuation to Three-Yellow Chickens"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2336-6681","authenticated-orcid":false,"given":"Weiwei","family":"Wang","sequence":"first","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Huang","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhonghua","family":"Ji","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guo","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuanzheng","family":"Qiao","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengya","family":"Shi","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Li","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teng","family":"Huang","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tianchao","family":"Wei","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3903-0509","authenticated-orcid":false,"given":"Meilan","family":"Mo","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiumiao","family":"He","sequence":"additional","affiliation":[{"name":"School of Marine Sciences and Biotechnology, Guangxi University for Nationalities, Nanning 530006, China"},{"name":"Guangxi Key Laboratory Cultivation Base for Polysaccharide Materials and Modifications, Guangxi University for Nationalities, Nanning 530006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1159-5145","authenticated-orcid":false,"given":"Ping","family":"Wei","sequence":"additional","affiliation":[{"name":"Institute for Poultry Science and Health, Guangxi University, Nanning 530005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1080\/03079450050045431","article-title":"Acute infectious bursal disease in poultry: A review","volume":"29","author":"Berg","year":"2000","journal-title":"Avian Pathol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"757","DOI":"10.2307\/1590995","article-title":"Lack of pathogenicity of five serotype 2 infectious bursal disease viruses in chickens","volume":"32","author":"Ismail","year":"1988","journal-title":"Avian Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1080\/03079458008418423","article-title":"Isolation and serological studies with infectious bursal disease viruses from fowl, turkeys and ducks: Demonstration of a second serotype","volume":"9","author":"McFerran","year":"1980","journal-title":"Avian Pathol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"511","DOI":"10.1136\/vr.90.18.511","article-title":"Immunosuppression by the infectious bursal agent in chickens immunised against Newcastle disease","volume":"90","author":"Allan","year":"1972","journal-title":"Vet. Rec."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"675","DOI":"10.1099\/0022-1317-75-3-675","article-title":"VP2 sequences of recent European \u2018very virulent\u2019 isolates of infectious bursal disease virus are closely related to each other but are distinct from those of \u2018classical\u2019 strains","volume":"75 Pt 3","author":"Brown","year":"1994","journal-title":"J. Gen. Virol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1136\/vr.125.10.271","article-title":"Outbreak of virulent infectious bursal disease in East Anglia","volume":"125","author":"Chettle","year":"1989","journal-title":"Vet. Rec."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"246","DOI":"10.1007\/s11262-012-0764-3","article-title":"Molecular epidemiology of infectious bursal disease viruses isolated from Southern China during the years 2000\u20132010","volume":"45","author":"He","year":"2012","journal-title":"Virus Genes"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1007\/BF01310671","article-title":"Heterogeneity of the antigenic site responsible for the induction of neutralizing antibodies in infectious bursal disease virus","volume":"119","author":"Oppling","year":"1991","journal-title":"Arch. Virol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"593","DOI":"10.1128\/jvi.32.2.593-605.1979","article-title":"Biophysical and biochemical characterization of five animal viruses with bisegmented double-stranded RNA genomes","volume":"32","author":"Dobos","year":"1979","journal-title":"J. Virol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1128\/jvi.31.3.584-589.1979","article-title":"The genome of infectious bursal disease virus consists of two segments of double-stranded RNA","volume":"31","author":"Muller","year":"1979","journal-title":"J. Virol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/0042-6822(85)90094-7","article-title":"The characterization and molecular cloning of the double-stranded RNA genome of an Australian strain of infectious bursal disease virus","volume":"143","author":"Azad","year":"1985","journal-title":"Virology"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1093\/emboj\/19.1.114","article-title":"A non-canonical lon proteinase lacking the ATPase domain employs the ser-Lys catalytic dyad to exercise broad control over the life cycle of a double-stranded RNA virus","volume":"19","author":"Birghan","year":"2000","journal-title":"EMBO J."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1006\/viro.2000.0595","article-title":"VP5, the nonstructural polypeptide of infectious bursal disease virus, accumulates within the host plasma membrane and induces cell lysis","volume":"277","author":"Lombardo","year":"2000","journal-title":"Virology"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"761","DOI":"10.1016\/j.cell.2005.01.009","article-title":"The birnavirus crystal structure reveals structural relationships among icosahedral viruses","volume":"120","author":"Coulibaly","year":"2005","journal-title":"Cell"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e00968-18","DOI":"10.1128\/JVI.00968-18","article-title":"The RNA-Binding Protein of a Double-Stranded RNA Virus Acts like a Scaffold Protein","volume":"92","author":"Mata","year":"2018","journal-title":"J. Virol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2221","DOI":"10.1099\/vir.0.19772-0","article-title":"VP1 of infectious bursal disease virus is an RNA-dependent RNA polymerase","volume":"85","author":"Gorbalenya","year":"2004","journal-title":"J. Gen. Virol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2481","DOI":"10.1007\/s007050170018","article-title":"The genome segment B encoding the RNA-dependent RNA polymerase protein VP1 of very virulent infectious bursal disease virus (IBDV) is phylogenetically distinct from that of all other IBDV strains","volume":"146","author":"Islam","year":"2001","journal-title":"Arch. Virol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1186\/s13567-018-0586-y","article-title":"Identification and assessment of virulence of a natural reassortant of infectious bursal disease virus","volume":"49","author":"Lisowska","year":"2018","journal-title":"Vet. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/j.bbrc.2006.09.040","article-title":"Genetic reassortment of infectious bursal disease virus in nature","volume":"350","author":"Wei","year":"2006","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/j.virol.2008.11.009","article-title":"Homologous recombination is apparent in infectious bursal disease virus","volume":"384","author":"He","year":"2009","journal-title":"Virology"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"574","DOI":"10.1637\/10053-010912-ResNote.1","article-title":"Molecular epidemiologic evidence of homologous recombination in infectious bursal disease viruses","volume":"56","author":"Jackwood","year":"2012","journal-title":"Avian Dis."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"108700","DOI":"10.1016\/j.vetmic.2020.108700","article-title":"Naturally occurring homologous recombination between novel variant infectious bursal disease virus and intermediate vaccine strain","volume":"245","author":"Wu","year":"2020","journal-title":"Vet. Microbiol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1016\/j.vetmic.2019.01.023","article-title":"Novel variant strains of infectious bursal disease virus isolated in China","volume":"230","author":"Fan","year":"2019","journal-title":"Vet. Microbiol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1016\/j.micpath.2016.02.004","article-title":"Isolation of novel variants of infectious bursal disease virus from different outbreaks in Northeast India","volume":"93","author":"Morla","year":"2016","journal-title":"Microb. Pathog."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"108507","DOI":"10.1016\/j.vetmic.2019.108507","article-title":"Novel variants of infectious bursal disease virus can severely damage the bursa of fabricius of immunized chickens","volume":"240","author":"Fan","year":"2020","journal-title":"Vet. Microbiol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"197833","DOI":"10.1016\/j.virusres.2019.197833","article-title":"Phylogenetic analyses and pathogenicity of a variant infectious bursal disease virus strain isolated in China","volume":"276","author":"Xu","year":"2020","journal-title":"Virus Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1006\/viro.2001.0947","article-title":"Induction of apoptosis in vitro by the 17-kDa nonstructural protein of infectious bursal disease virus: Possible role in viral pathogenesis","volume":"285","author":"Yao","year":"2001","journal-title":"Virology"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1873","DOI":"10.1007\/s00705-009-0524-4","article-title":"The VP5 protein of infectious bursal disease virus promotes virion release from infected cells and is not involved in cell death","volume":"154","author":"Wu","year":"2009","journal-title":"Arch. Virol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2647","DOI":"10.1128\/JVI.72.4.2647-2654.1998","article-title":"Generation of a mutant infectious bursal disease virus that does not cause bursal lesions","volume":"72","author":"Yao","year":"1998","journal-title":"J. Virol."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Wang, S., Hu, B., Si, W., Jia, L., Zheng, X., and Zhou, J. (2015). Avibirnavirus VP4 Protein Is a Phosphoprotein and Partially Contributes to the Cleavage of Intermediate Precursor VP4-VP3 Polyprotein. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0128828"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"6438","DOI":"10.1128\/JVI.77.11.6438-6449.2003","article-title":"The oligomerization domain of VP3, the scaffolding protein of infectious bursal disease virus, plays a critical role in capsid assembly","volume":"77","author":"Maraver","year":"2003","journal-title":"J. Virol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1473","DOI":"10.1099\/0022-1317-70-6-1473","article-title":"A conformational immunogen on VP-2 of infectious bursal disease virus that induces virus-neutralizing antibodies that passively protect chickens","volume":"70","author":"Fahey","year":"1989","journal-title":"J. Gen. Virol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2067","DOI":"10.1099\/0022-1317-80-8-2067","article-title":"Tissue culture infectivity of different strains of infectious bursal disease virus is determined by distinct amino acids in VP2","volume":"80","author":"Mundt","year":"1999","journal-title":"J. Gen. Virol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1563","DOI":"10.1099\/0022-1317-74-8-1563","article-title":"The genetic basis for the antigenicity of the VP2 protein of the infectious bursal disease virus","volume":"74 Pt 8","author":"Schnitzler","year":"1993","journal-title":"J. Gen. Virol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"6701","DOI":"10.1128\/JVI.74.15.6701-6711.2000","article-title":"Rescue of very virulent and mosaic infectious bursal disease virus from cloned cDNA: VP2 is not the sole determinant of the very virulent phenotype","volume":"74","author":"Boot","year":"2000","journal-title":"J. Virol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"3279","DOI":"10.1007\/s00705-014-2195-z","article-title":"Molecular epidemiology studies on partial sequences of both genome segments reveal that reassortant infectious bursal disease viruses were dominantly prevalent in southern China during 2000\u20132012","volume":"159","author":"He","year":"2014","journal-title":"Arch. Virol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1007\/s12250-019-00082-8","article-title":"Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan","volume":"34","author":"Hussain","year":"2019","journal-title":"Virol. Sin."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1016\/j.virol.2011.08.023","article-title":"Identification and pathogenicity of a natural reassortant between a very virulent serotype 1 infectious bursal disease virus (IBDV) and a serotype 2 IBDV","volume":"420","author":"Jackwood","year":"2011","journal-title":"Virology"},{"key":"ref_39","first-page":"209","article-title":"Very virulent infectious bursal disease virus: Reduced pathogenicity in a rare natural segment-B-reassorted isolate","volume":"87 Pt 1","author":"Rivallan","year":"2006","journal-title":"J. Gen. Virol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"6433","DOI":"10.3382\/ps\/pez498","article-title":"Identification and assessment of pathogenicity of a naturally reassorted infectious bursal disease virus from Henan, China","volume":"98","author":"Wang","year":"2019","journal-title":"Poult. Sci."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1016\/j.virusres.2007.08.013","article-title":"Reassortant infectious bursal disease virus isolated in China","volume":"131","author":"Wei","year":"2008","journal-title":"Virus Res."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1080\/03079457.2016.1139687","article-title":"Role of naturally occurring genome segment reassortment in the pathogenicity of IBDV field isolates in Three-Yellow chickens","volume":"45","author":"He","year":"2016","journal-title":"Avian Pathol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1016\/j.virol.2004.09.009","article-title":"VP1 protein of infectious bursal disease virus modulates the virulence in vivo","volume":"330","author":"Liu","year":"2004","journal-title":"Virology"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1007\/s00705-004-0405-9","article-title":"The enhanced virulence of very virulent infectious bursal disease virus is partly determined by its B-segment","volume":"150","author":"Boot","year":"2005","journal-title":"Arch. Virol."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"2767","DOI":"10.1128\/JVI.02360-12","article-title":"Both genome segments contribute to the pathogenicity of very virulent infectious bursal disease virus","volume":"87","author":"Escaffre","year":"2013","journal-title":"J. Virol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"8503","DOI":"10.1128\/JVI.00585-06","article-title":"Phylogenetic analysis reveals a correlation between the expansion of very virulent infectious bursal disease virus and reassortment of its genome segment B","volume":"80","author":"Hon","year":"2006","journal-title":"J. Virol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"20540","DOI":"10.1073\/pnas.0704447104","article-title":"Activation mechanism of a noncanonical RNA-dependent RNA polymerase","volume":"104","author":"Garriga","year":"2007","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"7385","DOI":"10.1073\/pnas.0611599104","article-title":"The structure of a birnavirus polymerase reveals a distinct active site topology","volume":"104","author":"Pan","year":"2007","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Nouen, C.L., Toquin, D., Muller, H., Raue, R., Kean, K.M., Langlois, P., Cherbonnel, M., and Eterradossi, N. (2012). Different domains of the RNA polymerase of infectious bursal disease virus contribute to virulence. PLoS ONE, 7.","DOI":"10.1371\/journal.pone.0028064"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1127","DOI":"10.1007\/s11427-017-9297-8","article-title":"N-terminal domain of the RNA polymerase of very virulent infectious bursal disease virus contributes to viral replication and virulence","volume":"61","author":"Gao","year":"2018","journal-title":"Sci. China Life Sci."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1016\/j.virol.2013.02.026","article-title":"A single amino acid V4I substitution in VP1 attenuates virulence of very virulent infectious bursal disease virus (vvIBDV) in SPF chickens and increases replication in CEF cells","volume":"440","author":"Yu","year":"2013","journal-title":"Virology"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"108458","DOI":"10.1016\/j.vetmic.2019.108458","article-title":"Serological study reveal different antigenic IBDV strains prevalent in southern China during the years 2000\u20132017 and also the antigenic differences between the field strains and the commonly used vaccine strains","volume":"239","author":"He","year":"2019","journal-title":"Vet. Microbiol."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1016\/j.vetmic.2018.04.024","article-title":"Antigenicity characterization of four representative natural reassortment IBDVs isolated from commercial three-yellow chickens from Southern China reveals different subtypes co-prevalent in the field","volume":"219","author":"Chen","year":"2018","journal-title":"Vet. Microbiol."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"646","DOI":"10.2307\/1592906","article-title":"Detection and persistence of infectious bursal disease virus in specific-pathogen-free and commercial broiler chickens","volume":"45","author":"Saif","year":"2001","journal-title":"Avian Dis."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/j.jviromet.2007.01.021","article-title":"An improved method for infectious bursal disease virus rescue using RNA polymerase II system","volume":"142","author":"Qi","year":"2007","journal-title":"J. Virol. Methods"},{"key":"ref_56","first-page":"887","article-title":"Cloning and sequencing analysis of the full-length genome from three isolates of very virulent infectious bursal disease virus","volume":"44","author":"Gao","year":"2014","journal-title":"Chin. Vet. Sci."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1099\/0022-1317-83-1-121","article-title":"Alteration of amino acids in VP2 of very virulent infectious bursal disease virus results in tissue culture adaptation and attenuation in chickens","volume":"83","author":"Zeyda","year":"2002","journal-title":"J. Gen. Virol."},{"key":"ref_58","unstructured":"Liu, T. (2016). Prokaryotic Expressions of IBDV Major Structural Proteins VP2, VP1 and the Development of Elisa Kits for the Detection of Antibody, Guangxi University."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"460","DOI":"10.2307\/1591208","article-title":"Immunogenicity of infectious bursal disease viruses in chickens","volume":"35","author":"Ismail","year":"1991","journal-title":"Avian Dis."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"108723","DOI":"10.1016\/j.vetmic.2020.108723","article-title":"The diagnosis and successful replication of a clinical case of Duck Spleen Necrosis Disease: An experimental co-infection of an emerging unique reovirus and Salmonella indiana reveals the roles of each of the pathogens","volume":"246","author":"Wang","year":"2020","journal-title":"Vet. Microbiol."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"456","DOI":"10.2307\/1589576","article-title":"Immunization Studies with a Cell-Culture-Adapted Infectious Bursal Disease Virus","volume":"23","author":"Skeeles","year":"1979","journal-title":"Avian Dis."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"11974","DOI":"10.1128\/JVI.75.24.11974-11982.2001","article-title":"Molecular determinants of virulence, cell tropism, and pathogenic phenotype of infectious bursal disease virus","volume":"75","author":"Brandt","year":"2001","journal-title":"J. Virol."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"1303","DOI":"10.1099\/0022-1317-71-6-1303","article-title":"A comparison of the sequences of segment A of four infectious bursal disease virus strains and identification of a variable region in VP2","volume":"71 Pt 6","author":"Bayliss","year":"1990","journal-title":"J. Gen. Virol."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"10346","DOI":"10.1128\/JVI.76.20.10346-10355.2002","article-title":"Exchange of the C-terminal part of VP3 from very virulent infectious bursal disease virus results in an attenuated virus with a unique antigenic structure","volume":"76","author":"Boot","year":"2002","journal-title":"J. Virol."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"969","DOI":"10.1007\/s00705-012-1256-4","article-title":"A simple and efficient method to rescue very virulent infectious bursal disease virus using SPF chickens","volume":"157","author":"Yu","year":"2012","journal-title":"Arch. Virol."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"13298","DOI":"10.1038\/s41598-020-70095-x","article-title":"Ex vivo rescue of recombinant very virulent IBDV using a RNA polymerase II driven system and primary chicken bursal cells","volume":"10","author":"Trombetta","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"246","DOI":"10.1007\/s11262-010-0499-y","article-title":"Molecular characteristics of segment B of seven very virulent infectious bursal disease viruses isolated in China","volume":"41","author":"Yu","year":"2010","journal-title":"Virus Genes"},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"2459","DOI":"10.1128\/JVI.77.4.2459-2468.2003","article-title":"Identification and molecular characterization of the RNA polymerase-binding motif of infectious bursal disease virus inner capsid protein VP3","volume":"77","author":"Maraver","year":"2003","journal-title":"J. Virol."}],"container-title":["Viruses"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1999-4915\/13\/1\/107\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:10:55Z","timestamp":1760159455000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1999-4915\/13\/1\/107"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,1,14]]},"references-count":68,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2021,1]]}},"alternative-id":["v13010107"],"URL":"https:\/\/doi.org\/10.3390\/v13010107","relation":{},"ISSN":["1999-4915"],"issn-type":[{"value":"1999-4915","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,1,14]]}}}