title: Comparative cytokine gene expression: regulation and release by human mast cells.
abstract: Since data on the ability of human mast cells to produce various cytokines are scanty, we examined the mRNA expression, its modulation and the resulting protein expression of a number of well-characterized cytokines, using semi-quantitative reverse transcription-polymerase chain reaction of cell extracts and enzyme-linked immunosorbent assays for analysis of cell supernatants. One million cells/ml of the human mast cell line HMC-1 were stimulated with 25 ng/ml phorbol myristate acetate (PMA), 5 x 10(-7) M calcium ionophore A 23187 (ionophore) or both stimuli combined for various time periods. Constitutive expression in unstimulated cells was found for interleukin-1 beta (IL-1 beta) -3, -4, -8, tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta). Maximal mRNA up-regulation was observed by 2-4 hr, with a second peak for TNF-alpha at 24 hr. After a 4-hr stimulation, IL-13 expression was detectable as well, whereas for IL-12, only the p35 but not the p40 chain was found, and IL-2, -5, -7 and interferon-gamma (IFN-gamma) were not expressed at all. Large quantities of IL-8, TNF-alpha, granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-3 were secreted time-dependently over a 72-hr period, with lower levels of IL-1 beta, -6, -10 and TGF-beta and no detectable IL-2, -4 and IFN-gamma protein. When IL-6 and IL-8 expression was compared in more detail, IL-6 mRNA was found to be up-regulated only with ionophore but not PMA, whereas both stimuli alone or combined increased IL-8 mRNA expression. Preincubation with cycloheximide inhibited IL-6 but not IL-8 transcription, and incubation of stimulated cells with actinomycin D stabilized IL-8 and also IL-6 mRNA. These data suggest a selective regulation of distinct cytokines in human mast cells at the transcriptional and post-transcriptional levels. Furthermore, the spectrum of cytokines produced by HMC-1 cells supports the well-recognized role of mast cells in immediate-type hypersensitivity reactions as well as their potential colony-stimulating and tissue-remodelling abilities.
authors.affiliation: Department of Dermatology, Charité-Virchow Clinics, Humboldt University, Berlin, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Möller
authors.forename: B M
authors.initials: BM
authors.lastname: Henz
authors.forename: A
authors.initials: A
authors.lastname: Grützkau
authors.forename: U
authors.initials: U
authors.lastname: Lippert
authors.forename: Y
authors.initials: Y
authors.lastname: Aragane
authors.forename: T
authors.initials: T
authors.lastname: Schwarz
authors.forename: S
authors.initials: S
authors.lastname: Krüger-Krasagakes
mesh_terms: D000001:Calcimycin / Q000276:immunology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000276:immunology*; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D008407:Mast Cells / Q000276:immunology*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D013755:Tetradecanoylphorbol Acetate / Q000276:immunology; D014407:Tumor Cells, Cultured / Q000276:immunology
chemical_list: D016207:Cytokines; D015850:Interleukin-6; D016209:Interleukin-8; D012333:RNA, Messenger; D000001:Calcimycin; D013755:Tetradecanoylphorbol Acetate