Properties of reticulum cell sarcomas in SJL/J mice: II. Fate of labeled tumor cells in normal and irradiated syngeneic mice

Transplantable reticulum cell sarcoma (RCS) cells were labeled with ³H-uridine or ³H-thymidine in vitro and injected intravenously into normal and irradiated syngeneic SJL/J mice. RCS cells exhibited typical B cell migration characteristics in peripheral lymphoid organs in both normal and irradiated recipients, localizing in follicles in a pattern resembling that of labeled normal bone marrow cells. However, over the first 72 hr after transfer, RCS cells diluted their label much less in irradiated than in normal recipients, reflecting their inability to proliferate in the irradiated hosts. The presence of unlabeled tumor cells did not significantly affect the distribution of labeled normal bone marrow or lymph node cells in the recipients. Thus, RCS fails to grow in irradiated recipients in spite of undisturbed homing characteristics and in the absence of any evidence of cytotoxic influences from the host.