title: Separation and functional studies of the human lymphokine-activated killer cell.
abstract: Cell separation studies were undertaken in an attempt to purify the lymphokine-activated killer (LAK) precursor cell. Null cells, prepared by the sequential depletion of monocytes, T- and B-lymphocytes from human peripheral blood mononuclear cells, were found to be potent mediators of LAK activity. Such preparations were Leu-11+ but Leu-4- and displayed high levels of natural killer activity. Incubation of these cells with recombinant interleukin 2 (IL-2) for periods in excess of 24 h induced LAK lysis of fresh tumor targets which were resistant to lysis by unstimulated null effectors. In contrast, lymphocytes which formed high affinity rosettes with sheep RBC (E+ lymphocytes) were poor mediators of both natural killer and LAK activity. Interleukin 2 stimulated null cells, retained a Leu-11+, Leu-4- phenotype, and expressed only low levels of receptors for IL-2 and transferrin. An increase in the number of binding sites, on null cells but not on T-cells, for Vicia villosa lectin with IL-2 stimulation was noted. Following IL-2 stimulation, null and T-cells were able to conjugate to K562 and fresh tumor but not to autologous lymphoblast targets.
mesh_terms: D002241:Carbohydrates / Q000032:analysis; D002469:Cell Separation; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000494:pharmacology*; D010641:Phenotype; D011971:Receptors, Immunologic / Q000032:analysis; D015375:Receptors, Interleukin-2; D011975:Receptors, Mitogen / Q000032:analysis; D011990:Receptors, Transferrin / Q000032:analysis
chemical_list: D002241:Carbohydrates; D008222:Lymphokines; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D011975:Receptors, Mitogen; D011990:Receptors, Transferrin