Transformation of cells by herpes simplex virus--fact or fantasy?

The replication of herpes simplex virus types 1 and 2 is defective in XC cells. One lesion is the failure of viral proteins to be transported to the cell nucleus. The resistance of XC cells to the toxic effects of herpes simplex virus is apparently not due directly to the presence of RNA tumor virus in these cells. Other cell lines transformed by RNA tumor viruses exhibited no comparable resistance. The nature of the association between HSV and cell for a number of generations after first selecting "transformants" is not yet established; on prolonged subculture, much of the original HSV information fails to be expressed. Not more than approximately to 0.1 viral genomes per cell remains permanently associated with the host DNA. The "transformants" retain the capacity to synthesize HSV-specific polypeptides, as determined by radioimmunoprecipitation. The "transformants" have a number of characteristics which distinguish them from parental cells, and such characteristics in the light of the immunological data suggest that XC cells exposed to HSV can permanently retain HSV-specific information.