GENETIC AND BIOLOGICAL DETERMINANTS OF AVIAN TUMOR VIRUS PATHOGENICITY, TRANSMISSION, AND EVOLUTION
Location: Avian Disease and Oncology Laboratory
Title: Insertion of reticuloendotheliosis virus long terminal repeat into CVI988 strain of Marek’s disease virus results in enhanced growth and protection
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: June 24, 2012
Publication Date: June 24, 2012
Citation: Lupiani, B., Lee, L.F., Sun, A., Witter, R.L., Reddy, S.M. 2012. Insertion of reticuloendotheliosis virus long terminal repeat into CVI988 strain of Marek’s disease virus results in enhanced growth and protection [abstract]. 9th International Symposium on Marek's Disease and Avian Herpesviruses, June 24-28, 2012, Freie Universitat Berlin. p. 31.
It has been reported that co-cultivation of a JM/102W strain, a virulent strain of Marek’s disease virus (MDV), with reticuloendotheliosis virus (REV) resulted in the integration of REV long terminal repeat (LTR) into the MDV repeat region. The resulting virus, RM1, was unable to transform T-cells but caused severe lymphoid organ atrophy in chickens. It has been shown that the LTR insertion into MDV genome results in altered expression of MDV genes. We inserted the REV LTR into MDV vaccine strain CVI988 virus to generate a virus designated CVRM. Pathogenesis studies showed that CVMR was not pathogenic in chickens and that it provided superior protection than the parental strain. Growth kinetics showed that CVRM replicated better than parental strain, suggesting the LTR insertion gives a replication advantage. We speculated that this enhanced growth properties of the virus are probably key for enhanced protection.