Author:

Keywords:

Animals, Cell Line, Genes, Viral, Immunization, Lymphocytes, Mice, Neoplasms, Experimental, Rats, Retroviridae, Sarcoma Viruses, Murine, Teratoma, Virus Activation, Science & Technology, Life Sciences & Biomedicine, Oncology, 1112 Oncology and Carcinogenesis, Oncology & Carcinogenesis, 3211 Oncology and carcinogenesis

Abstract:

A cell line (F3/1) derived from a rat embryonal carcinoma, originally induced in fetectomized rats injected with MSV, was found to be essentially non-immunogenic in a syngeneic host; the cells did not produce C-type virions. The MSV genome could be rescued by superinfection of F3/1 cells with endogenous C-type mouse virus and the cells were converted in a producer line-F3/1-P. The produced virus was shown to be MSV by its ability to induce focus formation in mouse fibroblasts. In contrast to its non-producer ancestor, the F3/1-P line proved to be strongly immunogenic in the syngeneic host. These results indicate the possibility of converting certain non-immunogenic tumors into immunogenic ones by the activation of dormant viral genome using xenogeneic non-oncogenic helper virus.