title: Isolation, identification, and gp85 characterization of a subgroup A avian leukosis virus from a contaminated live Newcastle Disease virus vaccine, first report in China.
abstract: To identify if any exogenous avian leukosis virus (ALV) exists in a live vaccine of poultry according to the directives of the Ministry of Agriculture of the People's Republic of China, a live vaccine strain of the Newcastle disease virus (NDV) was neutralized using an anti-NDV antibody, and was subsequently used to inoculate DF-1 cells to investigate the presence of exogenous ALV. The DF-1 cells were cultured for 21 d and subsequently screened using an ELISA for the p27 antigen of the ALV. An exogenous ALV, designated ALV-NDVP4, was identified. The nucleotide sequence of the gp85 gene of the ALV-NDVP4 was compared with those of the various subgroups of the ALV. The amino acid sequence identities for the predicted gp85 of the ALV-NDVP4 and those of the ALV reference strains ranged from 88.2 to 99.5% for the 12 of the subgroup A strains of ALV (ALV-A) and from 82.7 to 87.4% for the B, C, D, and E subgroup strains. The amino acid sequence identities for the gp85 of the ALV-NDVP4 and those of the subgroup J reference strains ranged from 48.7 to 49.9%. The ALV-NDVP4 shared the highest level of homology with the SDAU09C3 strain of ALV-A, which was isolated in China, suggesting a common origin. This is the first report of ALV-A contamination in a live vaccine for poultry in China. Our findings highlight the need for improved monitoring methods for poultry vaccine production.
authors.affiliation: College of Veterinary Medicine, Shandong Agricultural University, Tai'an, 271018, China zhaopeng@sdau.edu.cn.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhao
authors.affiliation: College of Veterinary Medicine, Shandong Agricultural University, Tai'an, 271018, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Dong
authors.affiliation: College of Veterinary Medicine, Shandong Agricultural University, Tai'an, 271018, China.
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Cui
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001353:Avian Leukosis / Q000517:prevention & control* / Q000821:virology; D001354:Avian Leukosis Virus / Q000235:genetics* / Q000302:isolation & purification; D002460:Cell Line; D002645:Chickens; D002681:China; D004340:Drug Contamination; D008969:Molecular Sequence Data; D009522:Newcastle disease virus / Q000276:immunology; D010802:Phylogeny; D011201:Poultry Diseases / Q000517:prevention & control* / Q000821:virology; D017422:Sequence Analysis, DNA; D014759:Viral Envelope Proteins / Q000235:genetics* / Q000378:metabolism; D014765:Viral Vaccines / Q000592:standards*
chemical_list: D014759:Viral Envelope Proteins; D014765:Viral Vaccines; C107403:glycoprotein 85, avian leukosis virus
keywords: Newcastle disease virus; contamination; gp85 gene; live vaccine; subgroup A of avian leukosis virus