title: Interleukin 1 receptor antagonist production in human monocytes is induced by IL-1 alpha, IL-3, IL-4 and GM-CSF.
abstract: Interleukin 1 receptor antagonist (IL-1ra) is induced in monocytes stimulated with lipopolysaccharide (LPS) or cultured on adherent immunoglobulin G (IgG). We examined the effects of various cytokines on monocyte IL-1ra protein production and compared it to IL-1 beta, which is regulated differently. IL-3 and GM-CSF induced near equivalent amounts of IL-1ra protein as does LPS. IL-1 alpha and IL-4 were weaker inducers. IL-3 and GM-CSF did not affect LPS or IgG induction of IL-1ra or LPS-induced IL-1 beta. However, our data confirmed that IL-4 up-regulated LPS-induced IL-1ra and down-regulated LPS-induced IL-1 beta. The kinetics of IL-1ra production by monocytes varied between stimulation with adherent IgG and cytokines or LPS. Cells cultured on adherent IgG exhibited a higher level of and more prolonged IL-1ra production. Relative IL-1ra mRNA levels after 8 h were in the order: adherent IgG > LPS or GM-CSF > IL-1 alpha, IL-3 or IL-4. The following cytokines failed to induce IL-1ra production: IL-2, IL-6, G-CSF, M-CSF, IFN-gamma, TGF beta 1, TGF beta 2, TNF alpha, acidic and basic FGF, PDGF and EGF. These results suggest that IL-1 alpha, IL-3, IL-4 and GM-CSF may play important roles in regulating monocyte IL-1ra production and that different mechanisms may be involved in induction of IL-1ra by adherent IgG in comparison to LPS or other cytokines.
authors.affiliation: Department of Medicine, University of Colorado Health Sciences Center, Denver 80262.
authors.forename: J K
authors.initials: JK
authors.lastname: Jenkins
authors.forename: W P
authors.initials: WP
authors.lastname: Arend
mesh_terms: D002478:Cells, Cultured; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D007074:Immunoglobulin G / Q000494:pharmacology; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000494:pharmacology; D007377:Interleukin-3 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D007378:Interleukins / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000097:blood; D012795:Sialoglycoproteins / Q000096:biosynthesis* / Q000097:blood
chemical_list: C507763:IL1RN protein, human; D007074:Immunoglobulin G; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D007377:Interleukin-3; D007378:Interleukins; D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D012795:Sialoglycoproteins; D015847:Interleukin-4; D016178:Granulocyte-Macrophage Colony-Stimulating Factor