Murine antibody-dependent cell-mediated cytotoxicity: failure to detect effector cells equivalent to human K cells
Tada, M.; Hinuma, S.; Abo, T.; Kumagai, K.
Journal of Immunology 124(4): 1929-1936
1980
ISSN/ISBN: 0022-1767 PMID: 7365244 Document Number: 158122
In antibody-dependent cell-mediated cytotoxicity (ADCC) systems directed toward chicken red blood cells (CRBC), effector cells were identified in murine mononuclear cells of bone marrow, peripheral blood, spleen and peritoneal exudate, but not thymus and lymph node. No effector activity could be detected in these cells from which phagocytic cells were depleted to undetectable levels or to less than 0.5% by iron- or silica-phagocytosis or nylon filtration. Potent effector activity was found in highly purified peritoneal macrophages. Effector activity in human peripheral blood mononuclear cells was found in nonadherent, nonphagocytic lymphoid cells and in adherent, phagocytic monocytes. In ADCC systems directed toward a mouse lymphoid cell line RL .male.1 and a human epitheloid cell line FL, a strong cytotoxicity, which appeared within 2 h after incubation and reached a maximum at 6 h, was produced by nonadherent, nonphagocytic cells of human peripheral blood. In contrast, a weak cytotoxicity against such nucleated cells, which appeared only when cultivated overnight, was produced by whole mononuclear cells but not by macrophage-depleted preparations of mouse peripheral blood and spleen. Purified peritoneal macrophages of normal mice exhibited a weak but significant effector activity to the antibody-coated nucleated cells, suggesting that the cytotoxicity in mice might be caused by macrophages contaminating the test preparations. The nonadherent, nonphagocytic effector cells, at least in an active form, equivalent to K cells present in human peripheral blood, may not be present in any lymphoid tissues of normal mice and the cells of the monocyte-macrophage series may be a major effector in mononuclear cell-mediated antibody-dependent cytotoxicity in mice.