NONSELECTIVE DESTRUCTION OF MURINE NEOPLASTIC-CELLS BY SYNGENEIC TUMORICIDAL MACROPHAGES

  • 1 January 1985
    • journal article
    • research article
    • Vol. 45  (1) , 14-18
Abstract
Tumor cells that were resistant to macrophage-mediated lysis were selected in vitro. Seven different heterogeneous murine [mouse] neoplasms (4 fibrosarcomas, a melanoma, a rhabdomyosarcoma and an osteogenic sarcoma) and 1 cloned line of a fibrosarcoma were incubated in vitro with syngeneic tumoricidal macrophages. Surviving tumor cells were recovered and expanded to undergo subsequent interaction with tumoricidal macrophages. After 6 sequential interactions, all cell lines were examined for their susceptibility to lysis mediated by murine peritoneal exudate macrophages activated with liposomes containing muramyl tripeptide phosphatidylethanolamine. In all 8 systems, no significant differences were detected between the parent tumor cells and cells that survived the sequential interactions. Neither macrophage infiltration into s.c. tumors nor the experimental or spontaneous metastatic potentials of the parenteral tumors differed from the lines established by cells surviving macrophage-mediated lysis. Tumor cell destruction by activated macrophages evidently is nonselective and does not lead to the development of resistant tumor cells nor to cells with altered metastatic properties.