title: Comparative analysis of receptor-binding specificity and pathogenicity in natural reassortant and non-reassortant H3N2 swine influenza virus.
abstract: Genetic reassortment between human and avian influenza viruses can create pandemic viruses. Influenza surveillance of pigs in Jilin Province, in China during 2007-2008 revealed that there were two distinguishable genotypes: a human-like H3N2 genotype and a double-reassortant genotype derived from the human H3N2 and avian H5 viruses. In this study, viral infection potential, replication kinetics, and pathogenicity were compared. The solid-phase binding assay demonstrated that both viruses prominently maintained a preference for the human-type receptor and the reassortant A/swine/Jilin/37/2008 (Sw/JL/37/08) showed relatively higher binding affinities than the non-reassortant A/swine/Jilin/19/2007 (Sw/JL/19/07). Replication kinetics showed that Sw/JL/37/08 had higher replicability in MDCK cells than Sw/JL/19/07. The mouse experiments clearly revealed that Sw/JL/37/08 had higher virulence than Sw/JL/19/07 as measured by more significant body weight loss, higher viral lung load, delayed viral clearance from lungs, and more severe pulmonary lesions. Sequence analysis indicated that the absence of glycosylation sites at residue 126 of HA and 93 of NA, as well as the characteristic NS1 C-terminal PL residues of ESEV may account for the increased replication and pathogenicity of Sw/JL/37/08. These results may imply that human may have infection risk by the reassortant swine influenza virus and emphasize the necessity for enhanced viral surveillance strategies, which monitor reassortment events in nature to reduce the public health threat posed by influenza viruses with the potential for human-to-human transmission currently circulating in pig populations.
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun, Jilin, China. Electronic address: congyanlong@126.com.
authors.forename: Yanlong
authors.initials: Y
authors.lastname: Cong
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Yixue
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Jilin Entry-Exit Inspection and Quarantine Bureau, Changchun, Jilin, China.
authors.forename: Weili
authors.initials: W
authors.lastname: Wang
authors.affiliation: Jilin Entry-Exit Inspection and Quarantine Bureau, Changchun, Jilin, China.
authors.forename: Qingfeng
authors.initials: Q
authors.lastname: Meng
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ran
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Lisai
authors.initials: L
authors.lastname: Zhu
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin, China.
authors.forename: Guilian
authors.initials: G
authors.lastname: Yang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin, China.
authors.forename: Wentao
authors.initials: W
authors.lastname: Yang
authors.affiliation: Development College, Jilin Agricultural University, Changchun, Jilin, China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Yang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin, China; Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun, Jilin, China. Electronic address: wangchunfeng@jlau.edu.cn.
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Wang
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Ding
mesh_terms: D000818:Animals; D002681:China; D004285:Dogs; D005260:Female; D006389:Hemagglutinins, Viral / Q000737:chemistry; D053122:Influenza A Virus, H3N2 Subtype / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity*; D008168:Lung / Q000473:pathology / Q000821:virology; D061985:Madin Darby Canine Kidney Cells; D051379:Mice; D008807:Mice, Inbred BALB C; D008958:Models, Molecular; D009976:Orthomyxoviridae Infections / Q000473:pathology / Q000821:virology*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016865:Reassortant Viruses / Q000737:chemistry / Q000378:metabolism* / Q000472:pathogenicity*; D014779:Virus Replication / Q000502:physiology
chemical_list: D006389:Hemagglutinins, Viral
keywords: H3N2 subtype; Pathogenicity; Reassortment; Receptor-binding specificity; Replication; Swine influenza virus