Glucocorticoid up-regulation of high-affinity interleukin 6 receptors on human epithelial cells.
Interleukin 6 (IL-6) is a potent pleiotropic cytokine, known, among others, to stimulate immunoglobulin production by B cells and to trigger acute-phase protein synthesis by hepatocytes. Similar to IL-1, it is produced by monocytes and macrophages following an inflammatory challenge. Analysis of IL-6 receptor (IL-6R) expression on different human cell lines indicates that dexamethasone could up-regulate the number of IL-6R on one epithelial cell line (UAC) and on two hepatoma cell lines (HepG2 and Hep3B). This effect was confirmed by Scatchard analysis of binding experiments, using [35S]methionine and [35S]cysteine metabolically labeled IL-6. It was confirmed at the level of mRNA expression by Northern blot analysis. These results provide evidence for a link between IL-6 and glucocorticoids. They could represent an example of a system in which one role of glucocorticoids is to define more accurately the target of cytokines, and they could explain, at least partly, the frequently observed synergy between IL-6 and glucocorticoids, notably in the case of hepatocytes.
Snyers
L
L
Department of Virology, Institut Pasteur du Brabant, Brussels, Belgium.
De Wit
L
L
Content
J
J
D006528:Carcinoma, Hepatocellular; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology*; D004848:Epithelium / Q000276:immunology; D004958:Estradiol / Q000494:pharmacology; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D007700:Kinetics; D008113:Liver Neoplasms; D011239:Prednisolone / Q000494:pharmacology*; D011374:Progesterone / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D011971:Receptors, Immunologic / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D019947:Receptors, Interleukin-6; D011994:Recombinant Proteins / Q000378:metabolism; D013739:Testosterone / Q000494:pharmacology; D015854:Up-Regulation / Q000187:drug effects*
D015850:Interleukin-6; D012333:RNA, Messenger; D011971:Receptors, Immunologic; D019947:Receptors, Interleukin-6; D011994:Recombinant Proteins; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol; D003907:Dexamethasone; D011239:Prednisolone