title: [Cytotoxicity of IFN-gamma-activated dendritic cells to freshly isolated acute myeloid leukemia cells].
abstract: To investigate the tumoricidal activity of dendritic cell (DC) stimulated by interferon-gamma (IFN-gamma) against freshly isolated myeloid leukemia cells and its mechanism, the peripheral blood monocytes collected from healthy donors were cocultured with interleukin-4 and granulocyte-macrophage colony-stimulating factor in medium to induce DC for 7 days. After 12 hour culture in the absence or presence of IFN-gamma, the changes of costimulatory molecules were analyzed with flow cytometry. To assay the cytotoxicity of DC against freshly isolated acute myeloid cells, they were cocultured at various effector-to-target ratio for 18 hours, then the percentage of tumoricidal activity was measured with (51)Cr release assay. To explore the mechanism of DC-mediated cytotoxicity, the change of DC surface or intracellular protein expression of Fas ligand (Fas L), TNF-alpha and TNF related apoptosis-inducing ligand (TRAIL) were analyzed with flow cytometry. The results showed that IFN-gamma enhanced cytotoxicity of DC against AML cells was (33.8 +/- 1.6)% at E:T as 20:1, compared with unstimulated DC (P < 0.05); IFN-gamma up-regulated expression of costimulatory molecules of DC surface such as CD86 and CD83; after stimulation with IFN-gamma, expression of intracellular TRAIL of DC was significantly enhanced, but expression of TRAIL on cell surface of DC was low; while the significant changes of Fas L and TNF-alpha expression neither on cell surface or in cells were not observed before or after stimulation with IFN-gamma. It is concluded that DC stimulated by IFN-gamma exhibit tumoricidal activity against AML cells. The cytotoxicity is partially related to maturation of DC and TRAIL inducing apoptosis, but not associated with death domain-independent mechanism of Fas L and TNF-alpha.
authors.affiliation: Department of Hematology, The Sixth Hospital of Shanghai Jiaotong University, Shanghai 200233, China. shijun7@hotmail.com
authors.forename: Jun
authors.initials: J
authors.lastname: Shi
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ji-Ying
authors.initials: JY
authors.lastname: Su
authors.forename: Xiao
authors.initials: X
authors.lastname: Li
authors.forename: Quan
authors.initials: Q
authors.lastname: Pu
authors.forename: Kazuma
authors.initials: K
authors.lastname: Ikeda
mesh_terms: D000208:Acute Disease; D015703:Antigens, CD / Q000032:analysis; D051940:B7-2 Antigen / Q000032:analysis; D018920:Coculture Techniques; D003602:Cytotoxicity, Immunologic / Q000187:drug effects* / Q000276:immunology; D003713:Dendritic Cells / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D053222:Fas Ligand Protein / Q000032:analysis; D005434:Flow Cytometry; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007371:Interferon-gamma / Q000494:pharmacology*; D007951:Leukemia, Myeloid / Q000276:immunology / Q000473:pathology; D008562:Membrane Glycoproteins / Q000032:analysis; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000032:analysis; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D000097802:CD83 Antigen
chemical_list: D015703:Antigens, CD; D051940:B7-2 Antigen; D053222:Fas Ligand Protein; D007136:Immunoglobulins; D007371:Interferon-gamma; D008562:Membrane Glycoproteins; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha; D000097802:CD83 Antigen