In vitro interactions of murine peritoneal macrophages and sarcoma cells. II. Induction of DNA synthesis in macrophages

Unstimulated peritoneal macrophages grown in vitro for 5 days do not incorporate thymidine. Sarcoma (AA) cells introduced to the culture on the fifth day die and disintegrate whereas the macrophages become markedly stimulated and autoradiography shows that they are triggered to synthesize DNA. In syngeneic cocultures up to 28% of the macrophages incorporate thymidine after 5 days of coculture.