title: Role of interferon-stimulated gene factor 3gamma and beta interferon in HLA class I enhancement in synovial fibroblasts upon infection with Chlamydia trachomatis.
abstract: Chlamydia trachomatis infection can cause reactive arthritis that is associated with the persistence of chlamydial organisms in the joint. Fibroblasts of the synovial membrane represent host cells for Chlamydia during articular infection. In this study we investigated the expression of HLA class I molecules in synovial fibroblasts following infection with C. trachomatis D. The expression of HLA class I heavy chain (HLA-I) was up-regulated in infected cultures as shown by reverse transcription-PCR and immunoblotting. The increase in cell surface expression of HLA-I and beta(2) microglobulin on infected fibroblasts was demonstrated by flow cytometric analysis. Suppression of enhanced production of interferon-stimulated gene factor 3gamma (ISGF3gamma) in infected cell cultures by antisense oligonucleotide treatment reduced the level of HLA-I. Blocking antibodies to beta interferon (IFN-beta) inhibited the Chlamydia-induced enhancement of both ISGF3gamma and HLA-I. These findings show that the up-regulation of HLA-I in synovial fibroblasts infected with C. trachomatis is caused by the induction of IFN-beta, which in turn stimulates the synthesis of ISGF3gamma, a transcription factor participating in the regulation of the HLA-I gene. The IFN-beta-mediated expression of HLA-I on Chlamydia-infected cells may be a regulatory factor in the immune response in chlamydial infections.
authors.affiliation: Institute of Medical Microbiology. Institute of Clinical Chemistry, Friedrich Schiller University of Jena, D-07740 Jena, Germany. juergen.roedel@med.uni-jena.de
authors.forename: Jürgen
authors.initials: J
authors.lastname: Rödel
authors.forename: Heinz
authors.initials: H
authors.lastname: Vogelsang
authors.forename: Katrin
authors.initials: K
authors.lastname: Prager
authors.forename: Matthias
authors.initials: M
authors.lastname: Hartmann
authors.forename: Karl-Hermann
authors.initials: KH
authors.lastname: Schmidt
authors.forename: Eberhard
authors.initials: E
authors.lastname: Straube
mesh_terms: D002478:Cells, Cultured; D002690:Chlamydia Infections / Q000276:immunology*; D002692:Chlamydia trachomatis / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000502:physiology*; D005347:Fibroblasts / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis*; D006801:Humans; D050832:Interferon-Stimulated Gene Factor 3; D050834:Interferon-Stimulated Gene Factor 3, gamma Subunit; D016899:Interferon-beta / Q000502:physiology*; D013582:Synovial Fluid / Q000166:cytology; D014157:Transcription Factors / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D015854:Up-Regulation
chemical_list: D004268:DNA-Binding Proteins; D015395:Histocompatibility Antigens Class I; C494227:IRF9 protein, human; D050832:Interferon-Stimulated Gene Factor 3; D050834:Interferon-Stimulated Gene Factor 3, gamma Subunit; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D016899:Interferon-beta