title: Modulation of MHC class II expression in human cells by dexamethasone.
abstract: The effect of dexamethasone on human MHC class II expression was examined on various cell types including lymphocytes, monocytes, and epithelial cells. Dexamethasone decreased the surface expression of HLA-DR and -DP, but not HLA-DQ, on lymphocytic cell lines that constitutively express these molecules. In addition, dexamethasome down-regulated the mRNA levels of HLA-DRA, but not of HLA-DQB, in Jijoye cells, a human lymphoblastic cell line. Similarly, dexamethasone decreased HLA-DR expression on epithelial and monocytic cell lines that express HLA-DR upon IFN-gamma treatment. In total, these results suggest that dexamethasone inhibits both constitutive and IFN-gamma-inducible MHC class II expression in several cell types. Moreover, these results indicate that the inhibitory effect of dexamethasone on MHC class II expression is selective for HLA-DR and -DP but not HLA-DQ. Possible mechanisms of dexamethasone-mediated regulation of MHC class II expression are discussed.
authors.affiliation: Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Schwiebert
authors.forename: R P
authors.initials: RP
authors.lastname: Schleimer
authors.forename: S F
authors.initials: SF
authors.lastname: Radka
authors.forename: S J
authors.initials: SJ
authors.lastname: Ono
mesh_terms: D000954:Antigens, Surface / Q000502:physiology; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology*; D004848:Epithelium / Q000187:drug effects; D005434:Flow Cytometry; D006681:HLA-D Antigens / Q000096:biosynthesis* / Q000187:drug effects* / Q000235:genetics; D006682:HLA-DP Antigens / Q000096:biosynthesis / Q000187:drug effects; D006683:HLA-DQ Antigens / Q000096:biosynthesis / Q000187:drug effects; D006684:HLA-DR Antigens / Q000096:biosynthesis / Q000187:drug effects; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D008214:Lymphocytes / Q000187:drug effects; D009000:Monocytes / Q000187:drug effects; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D000954:Antigens, Surface; D006681:HLA-D Antigens; D006682:HLA-DP Antigens; D006683:HLA-DQ Antigens; D006684:HLA-DR Antigens; D012333:RNA, Messenger; D003907:Dexamethasone; D007371:Interferon-gamma