NATURAL CYTO-TOXICITY ON TUMOR-CELLS OF HUMAN MACROPHAGES OBTAINED FROM DIVERSE ANATOMICAL SITES

  • 1 January 1980
    • journal article
    • research article
    • Vol. 39  (3) , 776-784
Abstract
Human mononuclear phagocytes were isolated from peripheral blood, peritoneal exudate and early lactation milk by adherence on microexudate-coated plastic and exposure to EDTA. Their cytolytic activity was measured as 3H-thymidine release from pre-labeled target cells over 48-72 h and cytostasis was evaluated in a spectrophotometric 72-h assay. The murine SV40-transformed mKSA-TU5 [kidney] line and the human E cell line, derived from an ovarian carcinoma, were employed as targets. Peripheral blood monocytes, in vitro-matured monocyte-derived macrophages, peritoneal macrophages and milk macrophages were all significantly cytolytic and cytostatic on these target cells at attacker to target cell ratios ranging from 5:1 to 40:1. When monocytes were cultivated in vitro, no loss of cytocidal capacity occurred over the first 10 days of culture; later, when epithelioid and giant cells predominate in the cultures, mononuclear phagocytes had little cytotoxic activity. Adherent cells obtained from cord blood or from the peripheral blood of old donors had natural cytotoxicity similar to monocytes obtained from young adult volunteers. Peripheral blood monocytes and peritoneal macrophages showed enhanced cytolytic activity after exposure to partially purified human fibroblast interferon. In the human mononuclear phagocyte series cytotoxicity on tumor cells is apparently not restricted to circulating monocytes but is also expressed by macrophages obtained from diverse anatomical sites.