A potent sarcoma virus was isolated after in vivo passage of a tumor arising spontaneously in a New Zealand White × New Zealand Black (B/ W) F1 hybrid mouse. Inoculation of the virus into mice, rats, hamsters, and Mastomys resulted in the rapid development of tumors at the sites of inoculation. The tumors induced in mice were sarcomas consisting of spindle cells and many inflammatory cells. Most tumors had a prominent angiomatous component. Tumor regressions occurred in some mice, while other tumors grew progressively, metastasized, and resulted in death. B/ W mice developed splenomegaly 4‐6 weeks after virus inoculation. The normal architecture of their spleens was completely destroyed and replaced by angiomatous tissue, fibrosis, and inflammatory changes. Virus‐induced tumors in hamsters consisted of undifferentiated polygonal cells. Virus‐induced tumors of rats and Mastomys consisted of thin‐walled blood vessels heavily infiltrated with polymorphonuclear leukocytes. Primary virus‐induced tumors in hamsters, rats, and Mastomys did not regress, but some transplanted hamster tumors regressed. Electron microscopy of virus‐induced and transplanted tumors revealed numerous type‐C virus particles morphologically similar to the murine leukemia‐sarcoma viruses. Tumor homogenates contained the group‐specific (gs) antigen of the murine leukemia‐sarcoma viruses.
ASJC Scopus subject areas
- Cancer Research