Detection of the meq gene in the T cell subsets from chickens infected with Marek's disease virus serotype 1.
The meq gene was thought to be only detected in Marek's disease virus serotype 1 (MDV 1) including a very virulent strain, Md5, while L-meq, in which a 180-bp sequence is inserted into the meq open reading frame, is found in other strains of MDV 1, such as CVI 988/R6. However, both meq and L-meq were previously detected by PCR in chickens infected with MDV 1, suggesting that MDV 1 may consists of at least two subpopulations, one with meq, the other with L-meq. To further analyze these subpopulations, we analyzed the time course changes in distribution of these subpopulations among T cell subsets from chickens infected with MDV 1. Both meq and L-meq were detected in CD4+ and CD8+ T cells infected with strain Md5 or CVI 988/R6. The shift in MDV subpopulations from one displaying meq to the other displaying L-meq and/or the conversion from meq to L-meq occurred mainly in the CD8+ T cell subset from Md5-infected chickens. PCR products corresponding to L-meq rather than meq were frequently amplified from the CD8+ T cell subset from CVI 988/R 6 -infected chickens. These results suggest that a dominant subpopulation of MDV 1 changes depending on the T cell subsets, and that L-meq is dominantly present in the CD8+ T cells which play a role in the clearance of pathogenic agents.
Chang
Kyung-Soo
KS
Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
Ohashi
Kazuhiko
K
Lee
Sung-Il
SI
Takagi
Michihiro
M
Onum
Misao
M
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000821:virology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000821:virology*; D002472:Cell Transformation, Viral / Q000276:immunology; D002645:Chickens; D008381:Herpesvirus 2, Gallid / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D007700:Kinetics; D008380:Marek Disease / Q000276:immunology / Q000821:virology*; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013047:Specific Pathogen-Free Organisms; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000821:virology*; D014774:Virulence
C100369:Eco-Q protein, Gallid herpesvirus 2; D009856:Oncogene Proteins, Viral; D012367:RNA, Viral