Vascular neoplasms induced in rodent central nervous system by murine sarcoma viruses

Mice and rats were injected intracerebrally with Harvey or Kirsten murine sarcoma viruses at 2 or 10 days after birth. Animals exhibited neurologic symptoms at 10 to 30 days postinjection. Brains, livers, and spleens were examined grossly and by light and electron microscopy. Mice injected at 2 days and rats injected at 10 days developed multiple brain neoplasms derived from endothelial cells. This conclusion was reinforced by immunofluorescence studies showing factor VIII expression on transformed cells both in vivo and in vitro. Brains of rats injected at 2 days contained both transformed endothelial and astroglial elements. Ultrastructural evidence for murine sarcoma virus replication was found in endothelial and glial cells of animals injected at 2 days; however, such evidence was not found in those injected at 10 days of age. The type of neoplasm induced appeared to be independent of concentration of inoculum, genetic strain within a species, or type of helper virus pseudotyped with the murine sarcoma virus. This system may facilitate the investigation of endothelial function and neoplasia.