Studies on the Infection of Human Cultured Leukocytes with Murine Rauscher Leukemia Virus 2. Heterotransplantation of a Human Lymphoblastoid Cell Line Chronically Infected with Epstein-Barr Virus and Rauscher Leukemia Virus

An Epstein-Barr virus (EBV) -positive human lymphoblastoid cell line chronically infected with Rauscher murine leukemia virus (RLV) was transplanted into antilymphocyte serum (ALS)- treated newborn hamsters. Four of 10 hamsters transplanted developed nonlethal regressive tumors which continued to shed C-type virus. Lymphoblastoid cell cultures reestablished from the heterotransplanted tumor cells were positive for both EBV capsid and murine gs-1 antigens. In contrast, all the hamsters transplanted with its parent cell line without RLV infection succumbed to lethal progressive tumors. The RLV-infected cells were shown to have cell surface antigen that was not found in the noninfected cells. It is postulated that new membrane antigen associated with C-type virus infection provoked more immunologic reaction even in ALS-treated hamsters, accounting for the reduced tumorigenicity of the RLV-infected human leukocytes.