title: Phylogenetic and antigenic analysis of avian infectious bronchitis virus in southwestern China, 2012-2016.
abstract: The aim of this study was to decipher the molecular epidemiological and antigenic characteristics of infectious bronchitis virus strains (IBVs) isolated in recent years in southwestern China. A total of 24 field strains were isolated from diseased chickens between 2012 and 2016. Phylogenetic analysis based on S1 nucleotide sequences showed that 16 of the 24 isolates were clustered into four distinct genotypes: QX (37.5%), TW (16.7%, TWI and TWII), Mass (8.3%), and J2 (4.2%). The QX genotype was still the prevalent genotype in southwestern China. Recombination analysis of the S1 subunit gene showed that eight of the 24 field strains were recombinant variants that originated from field strains and vaccine strains. A new potential recombination hotspot [ATTTT(T/A)] was identified, implying that recombination events may become more and more common. The antigenicity of ten IBVs, including seven field strains and commonly used vaccine strains, were assayed with a viral cross-neutralization assay in chicken embryonated kidney cells (CEK). The results showed that the ten IBVs could be divided into four serotypes (Massachusetts, 793B, Sczy3, and SCYB). Sczy3 and 793B were the predominant serotypes. Six of the seven field isolates (all except for cK/CH/SCYB/140913) cross-reacted well with anti-sera against other field strains. In conclusion, the genetic and antigenic features of IBVs from southwestern China in recent years have changed when compared to the previous reports. The results could provide a reference for vaccine development and the prevention of infectious bronchitis in southwestern China.
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: xiajing1028@163.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Xia
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: 18283583500@163.com.
authors.forename: Xiao
authors.initials: X
authors.lastname: He
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: 852883223@qq.com.
authors.forename: Ke-Chang
authors.initials: KC
authors.lastname: Yao
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: 709837510@qq.com.
authors.forename: Li-Jing
authors.initials: LJ
authors.lastname: Du
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: 496187459@qq.com.
authors.forename: Ping
authors.initials: P
authors.lastname: Liu
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: yanqigui@126.com.
authors.forename: Qi-Gui
authors.initials: QG
authors.lastname: Yan
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: yueliang5189@163.com.
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Wen
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: 1592334863@qq.com.
authors.forename: San-Jie
authors.initials: SJ
authors.lastname: Cao
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: 13993402@qq.com.
authors.forename: Xin-Feng
authors.initials: XF
authors.lastname: Han
authors.affiliation: College of Veterinary Medicine, Sichuan Agricultural University, Huimin Road, Wenjiang, Chengdu, Sichuan 611130, PR China. Electronic address: hyong601@163.com.
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000235:genetics; D002645:Chickens / Q000821:virology; D002681:China; D018352:Coronavirus Infections / Q000453:epidemiology / Q000276:immunology / Q000821:virology*; D005838:Genotype; D001351:Infectious bronchitis virus / Q000145:classification* / Q000235:genetics* / Q000276:immunology; D007668:Kidney / Q000821:virology; D008168:Lung / Q000821:virology; D017720:Molecular Epidemiology; D010802:Phylogeny
chemical_list: D000956:Antigens, Viral
keywords: Antigenic relatedness; Genotype; Infectious bronchitis virus; Recombination hotspot