title: Defining the involvement of p38alpha MAPK in the production of anti- and proinflammatory cytokines using an SB 203580-resistant form of the kinase.
abstract: Despite its lack of specificity, the inhibitor SB 203580 has been widely used to implicate p38 mitogen-activated protein kinase (MAPK) in the synthesis of many cytokines. Here we show unequivocally that the production of interleukin (IL)-1beta, IL-6, IL-10, and tumor necrosis factor alpha (TNFalpha) requires p38 MAPK activity by demonstrating that the inhibitory effects of SB 203580 were reversed by expression of an SB 203580-resistant form of p38alpha (SBR-p38alpha) that fails to bind to SB 203580. This strategy established the requirement for p38 activity for the lipopolysaccharide-stimulated production of IL-10, IL-1beta, and IL-6 by the monocytic cell WEHI 274 and the production of IL-6 and TNFalpha stimulated by ligation of the Fc-gamma receptor of the mast cell MC/9. Expression of SBR-p38alpha in primary macrophages abrogated the ability of SB 203580 to inhibit the lipopolysaccharide-stimulated production of TNFalpha but not of IL-10. Expression of SBR-p38alpha in primary T lymphocytes abrogated the ability of SB 203580 to inhibit the production of interferon-gamma induced by co-ligation of CD3 and CD28 but not the production of interferon-gamma or IL-10 induced by IL-12. These results suggest that the levels of p38 MAPK activity required for maximal cytokine production vary with different cytokines and stimuli.
authors.affiliation: Biomedical Research Centre, University of British Columbia, 2222 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.
authors.forename: Xuecui
authors.initials: X
authors.lastname: Guo
authors.forename: Robert E
authors.initials: RE
authors.lastname: Gerl
authors.forename: John W
authors.initials: JW
authors.lastname: Schrader
mesh_terms: D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology*; D007249:Inflammation; D007371:Interferon-gamma / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology*; D048308:Mitogen-Activated Protein Kinase 14; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology
chemical_list: D016207:Cytokines; D004791:Enzyme Inhibitors; D007093:Imidazoles; D008070:Lipopolysaccharides; D011725:Pyridines; D016753:Interleukin-10; D007371:Interferon-gamma; D048308:Mitogen-Activated Protein Kinase 14; D020928:Mitogen-Activated Protein Kinases; C093642:SB 203580