Homologous Transfer of Rous Sarcoma by Cells2

Abstract

Primary Rous sarcomas induced by virus were transplanted homologously in solid or ascites form. A sex chromosome marker was used to distinguish transplanted cells from tumor cells induced in the recipient by Rous virus infection. The events after transfer of Rous cells bore a superficial resemblance to transplantation, but virus infection and induction of Rous cells were found to be the quantitatively dominating process. Only in the early stages of tumor development were any numbers of dividing transplanted cells identified. In old ascites or solid tumors almost all metaphases were derived from host elements. When graded amounts of Rous cells were inoculated, doses larger than 4 × 10⁵ cells had to be used to get any detectable metaphases derived from the original Rous cells. In a second transplant generation, less than 0.5 percent of the metaphases were of the same sex as the original Rous cells.