Latency and reactivation of Marek's disease virus in B lymphocytes transformed by avian leukosis virus

• Published in: Journal of general virology Vol. 74; no. 10; pp. 2163 - 2170
• Main Authors: Fynan, E.F, Ewert, D.L, Block, T.M
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01.10.1993; Society for General Microbiology
• Subjects: Alpharetrovirus - physiology; Animals; avian leukosis virus; avian oncovirus; Azacitidine - pharmacology; B-lymphocytes; B-Lymphocytes - microbiology; Biological and medical sciences; cell culture; Cell Line; cell lines; Cell Transformation, Viral - physiology; Chick Embryo; DNA; DNA, Viral - analysis; DNA, Viral - drug effects; Fundamental and applied biological sciences. Psychology; Herpesvirus 2, Gallid - isolation & purification; Herpesvirus 2, Gallid - physiology; lymphocyte proliferation; Mardivirus; Methylation - drug effects; Microbiology; poultry; Replicative cycle, interference, host-virus relations, pathogenicity, miscellaneous strains; Virology; Virus Latency - physiology; Gammaherpesvirinae; Marek disease virus; Oncovirinae; Reactivation; Herpesviridae; Transformed cell; Retroviridae; Virus replication cycle; B-Lymphocyte; Latency; Virus; Type C oncovirus; DNA; Persistent infection; Avian leukosis virus; Methylation; Tumor cell
• DOI: 10.1099/0022-1317-74-10-2163
• ISSN: 0022-1317

The physical and biological state of the Marek's disease virus (MDV) genome in avian leukosis virus (ALV)-transformed cells is characterized using cell lines established from ALV tumours co-infected with the SB-1 strain of MDV. The MDV genome within the ALV-transformed cells was found to be methylated at 5' CpG 3' dinucleotides. Less than 2% of the tumour cells expressed MDV antigen and only one virus plaque that was characteristic of an MDV infection was noted when tumour cells were cocultured with fibroblasts permissive for a productive MDV infection. However, when methylation of the MDV genome was prevented by culturing the tumour cell lines in the presence of 5-azacytidine, both MDV antigen expression and viral replication increased. Based on these results, it appears that MDV resides within the ALV-transformed cells in a latent state and that MDV latency might be influenced, to some extent, by methylation of the MDV genome.