Functional heterogeneity of Sarcoma I cells in transplantation experiments

Cell suspensions prepared from Sarcoma I (SaI) allografts at various stages of development in C57BL10/ScSn (B10) mice immunosuppressed with xenogeneic antithymocyte serum (ATS) were adoptively transferred into secondary syngeneic (A/Ph) and allogeneic (B10) recipients. In the syngeneic recipients, a gradual decrease in the tumorigenic capacity of transferred suspensions was proved, while in the allogeneic recipients the tumorigenic activity was proved in early and late periods. The suspensions from the period of both permanently and temporarily regressing tumors showed a suppressed growth capacity in syngeneic and immunosuppressed allogeneic recipients. On the other hand, the suspensions from growing tumors produced in both types of secondary recipients a sharp and permanent growth. The data obtained suggest changes in functional properties of SaI cells during the course of their development in allogeneic recipients.