TUMOR METASTASIS IN MICE WITH REDUCED IMMUNE REACTIVITY .4. RESTORATION OF RELATIVE RESISTANCE TO METASTASIS FORMATION IN THYMECTOMIZED SUB-LETHALLY IRRADIATED MICE BY SPLEEN-CELLS

  • 1 January 1975
    • journal article
    • research article
    • Vol. 10  (4) , 299-305
Abstract
Adult thymectomy and/or sub-lethal irradiation increased spontaneous metastasis formation in several syngeneic murine systems (MCA[methylcholanthrene]-induced sarcomas MCG101 in C57BL/6J mice, MCG12 in CBA mice and MCA-induced epidermoid carcinoma EpCal in CBA mice). To differentiate between immunological and non-immunological effects of these treatments on tumor spread, the effects of presumed selective restoration of immune competence by transfer of syngeneic spleen cells from normal donors shortly after irradiation (1.5 mo. before tumor transplantation) was performed. This procedure brought the resistance of thymectomized irradiated mice to tumor spread back to the level seen in untreated mice, providing further evidence that the increase of tumor spread in this experimental model to a major part was immune-mediated. In thymectomized irradiated mice adoptive transfer of concomitant immunity by spleen cells from tumor-bearing mice soon after tumor transplantation completely inhibited the spread of the highly antigenic MCG101 and reduced that of the weakly antigenic MCG12 to control level. Adoptive transfer after tumor resection has no significant effect on the spread of either of the tumors.