title: Natural killer cell-mediated inhibition of growth of myeloid and lymphoid clonogenic leukemias.
abstract: We have shown that peripheral blood (PB) lymphocytes of normal donors inhibit colony formation by myeloid (K-562) and lymphoid (Molt-4) leukemia cell lines in a clonogenic assay in vitro. The inhibitor cells were identified as natural killer (NK) cells based on their large granular lymphocyte (LGL) morphology and CD16+CD5- cell surface phenotype. The levels of inhibition were dependent both on the leukemia: effector (L:E) cell ratio, as well as on the time of preincubation of the leukemic and effector cells; maximum inhibition was observed at a 1:20 L:E cell ratio, and required 6-16 h preincubation of the leukemia and effector cells. Colony formation of both K-562 and Molt-4 was also inhibited by a soluble factor derived from coculture of K-562 and PB lymphocytes. The finding that the growth of clonogenic Molt-4 cells was almost completely abolished following treatment with interferon (IFN)-alpha rA in the dose of 10(3) U/ml, whereas growth of K-562 cells was only slightly affected by similar treatment, suggested that NK cells may mediate inhibition of clonogenic leukemias through various mechanisms.
authors.affiliation: Department of General Surgery, University of Texas, Houston 77030.
authors.forename: C A
authors.initials: CA
authors.lastname: Savary
authors.forename: E
authors.initials: E
authors.lastname: Lotzová
mesh_terms: D002455:Cell Division; D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007111:Immunity, Cellular; D007165:Immunosuppression Therapy; D007694:Killer Cells, Natural / Q000276:immunology*; D055646:Killer Factors, Yeast; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000276:immunology / Q000473:pathology*; D015458:Leukemia, T-Cell / Q000276:immunology / Q000473:pathology*; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000473:pathology*; D011506:Proteins / Q000502:physiology; D014410:Tumor Stem Cell Assay
chemical_list: D055646:Killer Factors, Yeast; D011506:Proteins