Interleukin-4 suppresses granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor levels in stimulated human monocytes.
Granulocyte colony-stimulating factor (G-CSF) was quantitated in the supernatants of lipopolysaccharide (LPS)-treated human monocytes by ELISA. Unlike previous reports, the lymphokines, interleukin-4 (IL-4) and interferon-gamma (IFN-gamma), were unable to induce the synthesis of G-CSF. Both IL-4 (> or = 10 pM) and the glucocorticoid, dexamethasone (10(-7) M), inhibited G-CSF production in the LPS-treated monocytes; in contrast, IFN-gamma had a weak potentiating effect on the LPS action. Changes in antigen expression were manifested at the level of messenger RNA (mRNA). Granulocyte-macrophage (GM)-CSF in the LPS-treated monocyte supernatants was also quantitated by ELISA but its levels were somewhat lower than for G-CSF; IL-4, dexamethasone and IFN-gamma had similar effects on GM-CSF levels as on G-CSF levels. The suppression of CSF production in the stimulated monocytes by IL-4 and glucocorticoid extends the list of monocyte cytokines whose levels can be down-regulated by these agents and suggests another potential anti-inflammatory and immunosuppressive function for IL-4.
Hamilton
J A
JA
University of Melbourne, Department of Medicine, Parkville, Australia.
Whitty
G A
GA
Royston
A K
AK
Cebon
J
J
Layton
J E
JE
D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology; D016179:Granulocyte Colony-Stimulating Factor / Q000096:biosynthesis*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis*; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D015847:Interleukin-4 / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology
D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D015847:Interleukin-4; D003907:Dexamethasone; D007371:Interferon-gamma; D016178:Granulocyte-Macrophage Colony-Stimulating Factor