title: Inhibition of endogenous MHC class II-restricted antigen presentation by tacrolimus (FK506) via FKBP51.
abstract: The effect of tacrolimus (FK506) on down-regulation of IL-2 production by T cells is considered to be mainly responsible for its strong suppression of immunological events. In this study, we show that FK506 also has an affect on antigen presentation by antigen-presenting cells in vitro. FK506 was able to inhibit the presentation of endogenous MHC class II-restricted minor histocompatibility antigens in primary dendritic cells (DC) in vitro, but cyclosporine A (CsA) and rapamycin (RAP) were not. RNA interference (RNAi)-mediated reduction of endogenous FK506-binding protein (FKBP)51 expression resulted in a marked decrease in antigen presentation, suggesting that FKBP51 plays a role in endogenous MHC class II-restricted antigen presentation. Since our model used naturally expressed cytosolic antigens in primary DC, these effects might have been due to novel properties of the immunosuppressive drugs and may allow us to elucidate a new paradigm for the immunosuppressive mechanism of FK506.
authors.affiliation: Department of Plastic Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Imai
authors.forename: Hiroeki
authors.initials: H
authors.lastname: Sahara
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Tamura
authors.forename: Kowichi
authors.initials: K
authors.lastname: Jimbow
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Saito
authors.forename: Kyori
authors.initials: K
authors.lastname: Ezoe
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Yotsuyanagi
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Sato
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000187:drug effects*; D015153:Blotting, Western; D019556:COS Cells; D002522:Chlorocebus aethiops; D016572:Cyclosporine / Q000494:pharmacology; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology; D005434:Flow Cytometry; D015870:Gene Expression / Q000187:drug effects; D000949:Histocompatibility Antigens Class II / Q000187:drug effects* / Q000276:immunology; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D051379:Mice; D010047:Ovalbumin / Q000276:immunology; D034622:RNA Interference; D020123:Sirolimus / Q000494:pharmacology; D016559:Tacrolimus / Q000494:pharmacology*; D022021:Tacrolimus Binding Proteins / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D014162:Transfection; D000099159:Tacrolimus Binding Protein 5
chemical_list: D016572:Cyclosporine; D000949:Histocompatibility Antigens Class II; D007166:Immunosuppressive Agents; D010047:Ovalbumin; D020123:Sirolimus; D016559:Tacrolimus; D022021:Tacrolimus Binding Proteins; D000099159:Tacrolimus Binding Protein 5