title: Role of interferon gamma and tumour necrosis factor alpha in monocyte-mediated cytostasis and cytotoxicity against a human histiocytic lymphoma cell line.
abstract: In view of cellular adoptive immunotherapy we have studied monocyte-mediated cytostasis and cytotoxicity against U 937 cells, a human histiocytic lymphoma cell line. Highly purified human monocytes and monocyte-derived macrophages were activated with interferon gamma (IFN) or tumour necrosis factor alpha (TNF) to antileukemic immune effector cells. Antileukemic activity of human monocytes was dependent on monocyte differentiation into macrophages and on a dose- and time-dependent activation with IFN or TNF. Maximum cytostasis of 97.0 +/- 0.7% (mean +/- SEM) (conventional [3H]dT uptake assay) and 81.9 +/- 5.3% cytotoxicity (modified MTT assay) of U 937 cells was obtained by monocytes activated with 100 U/ml IFN for at least 24 h at an effector-to-target-cell ratio of 10. U 937 cells premodified with IFN showed an increase in susceptibility to monocyte-mediated cytotoxicity. U 937 cells premodified with TNF were almost resistant to monocyte-mediated cytotoxicity while activated monocytes maintained their cytotoxic potential. These data show that IFN and TNF are potent activators of monocyte-mediated cytotoxicity. Furthermore, IFN and TNF might be involved in the regulation of the susceptibility of leukemic cells to lysis by interactions with monocytes or macrophages.
authors.affiliation: Department of Haematology, University Hospital, Amsterdam, The Netherlands.
authors.forename: A A
authors.initials: AA
authors.lastname: van de Loosdrecht
authors.forename: G J
authors.initials: GJ
authors.lastname: Ossenkoppele
authors.forename: R H
authors.initials: RH
authors.lastname: Beelen
authors.forename: M G
authors.initials: MG
authors.lastname: Broekhoven
authors.forename: M M
authors.initials: MM
authors.lastname: Langenhuijsen
mesh_terms: D016923:Cell Death; D003124:Colorimetry / Q000379:methods; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D006801:Humans; D016219:Immunotherapy, Adoptive; D007371:Interferon-gamma / Q000494:pharmacology*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology / Q000628:therapy*; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D011994:Recombinant Proteins; D013778:Tetrazolium Salts / Q000378:metabolism; D013844:Thiazoles / Q000378:metabolism; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D011994:Recombinant Proteins; D013778:Tetrazolium Salts; D013844:Thiazoles; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; C022616:thiazolyl blue