Prevalence and molecular characterization of meq in feather follicular epithelial cells of Korean broiler chickens.
Marek's disease (MD) is a highly contagious lymphoproliferative disease of chickens. Meq is the relevant oncogene and four isoforms, long (L)-meq, meq, short (S)-meq and very short (VS)-meq, have been identified. Although MD is important in the poultry industry, the prevalence and molecular properties of Korean MD virus (MDV) among broiler chickens remain unclear. Therefore, we characterized meq in pooled feather tips sampled at 3- and 5-week-old chickens from 21 unvaccinated and 22 vaccinated broiler farms via nested-PCR and nucleotide sequence analysis. Multiple bands consisting of L-meq, meq, and S-meq amplicons were observed in a commercial vaccine (CVI988 + HVT), 1 (4.8%) and 5 samples (22.7%) from unvaccinated and vaccinated farms, respectively. A strong meq amplicon was observed in a MD-related tumor tissue, 6 (28.6%) and 1 (4.5%) samples from unvaccinated and vaccinated farms, respectively. Six and one amplicons from unvaccinated (28.6%) and vaccinated farms (4.5%), respectively, were differentiated from CVI988 by nucleotide sequence analysis. Therefore, the relatively high rate of meq in the unvaccinated broiler farms constitutes support for vaccination. However, the existence of CVI988-related meq in unvaccinated chickens necessitates further study regarding the origins and pathoimmunological effects of the viruses on chickens.
Kang
Jung-Won
JW
Department of Microbiology, Seoul National University, Seoul 151-742, Korea.
Cho
Sun-Hee
SH
Mo
In-Pil
IP
Lee
Dong-Woo
DW
Kwon
Hyuk-Joon
HJ
D000818:Animals; D002642:Chick Embryo; D002645:Chickens / Q000821:virology*; D004847:Epithelial Cells / Q000378:metabolism / Q000821:virology*; D005241:Feathers / Q000166:cytology / Q000378:metabolism / Q000821:virology*; D008381:Herpesvirus 2, Gallid / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D008113:Liver Neoplasms / Q000821:virology; D008380:Marek Disease / Q000821:virology; D008969:Molecular Sequence Data; D009856:Oncogene Proteins, Viral / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D011201:Poultry Diseases / Q000821:virology; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein
C100369:Eco-Q protein, Gallid herpesvirus 2; D009856:Oncogene Proteins, Viral; D020033:Protein Isoforms