ARS | Publication request: ROLE OF THE GENE PP38 IN THE PATHOGENESIS OF MAREK'S DISEASE VIRUS

Submitted to: World Veterinary Poultry Association Congress Proceedings
Publication Type: Proceedings
Publication Acceptance Date: July 19, 2003
Publication Date: July 31, 2003
Citation: Gimeno, I.M., Hunt, H.D., Witter, R.L., Neumann, U., Reddy, S., Silva, R.F. 2003. Role of the gene pp38 in the pathogenesis of marek's disease virus. World Veterinary Poultry Association Congress Proceedings. p. 101.

Technical Abstract: The biological function of the gene pp38 in the pathogenesis of Marek's disease virus (MDV) is presented. Expression of pp38 was chronologically studied in different tissues of birds infected with rMd5, a recombinant virus homologous to the wild type strain of Md5 (very virulent MDV). Also, the pathogenesis of a knockout virus (rMd5?pp38), in which the gene pp38 has been deleted was studied. Deletion of pp38 impaired totally the cytolytic infection in lymphoid cells but not in the feather follicle epithelium. Transformation of lymphoid cells, however, occurs. The frequency of gross tumors was drastically reduced in the group inoculated with rMd5?pp38. However, the cell elements integrating the tumor were of the same phenotype as those transformed by rMd5 (CD4+, CD8-, meq+, MATSA+). Histologically, higher frequency of lymphoproliferative lesions was observed. Nonetheless, lesions compatible with apoptosis were observed and the role of pp38 in blocking apoptosis as well as in regulation of the cell cycle is discussed.