Rescue of avian leukosis subgroup J associated acutely transforming viruses carrying different lengths of the v fps oncogene and analysis of their tumorigenicity
In our previous study, six subgroup J strains of avian leukosis virus (ALV J) associated acutely transforming viruses carrying different lengths of the v fps oncogene, designated as Fu J and Fu J1 5, were isolated and characterized from fibrosarcomas in ALV J infected chickens. In the present study, the oncogenic potential of Fu J and Fu J1 5 was investigated using a reverse genetics technique. Six replication defective viruses, named rFu J and rFu J1 5, were rescued with the replication competent rescued ALV J strain rSDAU1005 as a helper virus by co transfection of chicken embryo fibroblast monolayers with infectious clone plasmids. Experimental bird studies were performed, demonstrating that only the rescued rFu J virus carrying the complete v fps oncogene with rSDAU1005 as the helper virus could induce acute fibrosarcoma after inoculation in specific pathogen free (SPF) chickens. These results provide direct evidence that the replication defective acutely transforming Fu J virus, with the complete v fps oncogene, was associated with acute fibrosarcoma in chickens infected with ALV J in the field, as reported previously.
Archives of Virology