A spontaneous transplantable osteogenic sarcoma in AKR/Ms mice.

A transplantable osteogenic sarcoma originally arising in the right femur of an AKR/Ms male mouse is described. The original tumor showed a conspicuous bone and cartilage formation, but the capability of forming the bone was lost in the 4th transplant generation and that of cartilage formation was lost in the 7th generation. Alkaline phosphatase activity was histochemically demonstrated in only a few tumor cells, and the activity did not rise in the host serum. Intracisternal type-A particles of an average diameter of 70 nm were abundant in the rough endoplasmic reticulum, while type-C particles were rarely found to be budding from the cell surface or free in the extracellular spaces by electron microscopy. Three of the 27 thymectomized AKR mice that had been neonatally injected with cell-free material of the transplanted tumor developed osteomas, but no osteogenic sarcoma was found.