title: Effect of SOCS1 overexpression on RPE cell activation by proinflammatory cytokines.
abstract: The purpose of this study was to investigate the in vitro effect of Suppressor Of Cytokine Signaling 1 (SOCS1) overexpression in retinal pigment epithelium (RPE) cells on their activation by pro-inflammatory cytokines IFNγ, TNFα and IL-17. Retinal pigment epithelium cells (ARPE-19) were stably transfected with the control plasmid pIRES2-AcGFP1 or the plasmid pSOCS1-IRES2-AcGFP1. They were stimulated by IFNγ (150ng/ml), TNFα (30ng/ml) or IL-17 (100ng/ml). The levels of SOCS1 mRNA were measured by real-time PCR. Signal Transducer and Activator of Transcription 1 (STAT1) phosphorylation and IκBα expression were analysed by western Blot (WB). IL-8 secretion was analysed by ELISA and expression of MHCII molecules and ICAM-1/CD54 by flow cytometry. Our data show that SOCS1 mRNA overexpression in RPE cells prevents IFNγ-induced SOCS1 mRNA increase and IFNγ-mediated STAT1 phosphorylation. Moreover, SOCS1 overexpression in RPE cells inhibits IFNγ-induced decrease of IL-8 secretion and prevents IFNγ-induced MHC II and ICAM1/CD54 upregulation. However, SOCS1 overexpression does not affect TNFα-induced IκBα degradation nor block TNFα-induced or IL-17-induced IL-8 secretion. On the contrary, IL-17-induced secretion is increased by SOCS1 overexpression. In conclusion, SOCS1 overexpression in RPE cells inhibits some IFNγ-mediated responses that lead to uveitis development. This notion raises the possibility that SOCS1 overexpression could be a novel target for treating non-infectious uveitis. However, some proinflammatory effects of TNFα and IL-17 stimulation on RPE are not blocked by SOCS1 overexpression.
authors.affiliation: I.R.I.B.H.M (Institute of Interdisciplinary Research), Université Libre De Bruxelles Campus Erasme, Brussels, Belgium; Department of Ophthalmology, CHU St-Pierre and Brugmann, Brussels, Belgium. Electronic address: mbazewic@ulb.ac.be.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bazewicz
authors.affiliation: I.R.I.B.H.M (Institute of Interdisciplinary Research), Université Libre De Bruxelles Campus Erasme, Brussels, Belgium; Department of Ophthalmology, CHU St-Pierre and Brugmann, Brussels, Belgium.
authors.forename: Dafina
authors.initials: D
authors.lastname: Draganova
authors.affiliation: I.R.I.B.H.M (Institute of Interdisciplinary Research), Université Libre De Bruxelles Campus Erasme, Brussels, Belgium.
authors.forename: Maya
authors.initials: M
authors.lastname: Makhoul
authors.affiliation: I.R.I.B.H.M (Institute of Interdisciplinary Research), Université Libre De Bruxelles Campus Erasme, Brussels, Belgium.
authors.forename: Abdel
authors.initials: A
authors.lastname: Chtarto
authors.affiliation: Department of Ophthalmology, CHU St-Pierre and Brugmann, Brussels, Belgium.
authors.forename: Valerie
authors.initials: V
authors.lastname: Elmaleh
authors.affiliation: Clinical Neurosciences Department, Lausanne University Hospital, Lausanne, Switzerland.
authors.forename: Liliane
authors.initials: L
authors.lastname: Tenenbaum
authors.affiliation: Department of Ophthalmology, CHU St-Pierre and Brugmann, Brussels, Belgium.
authors.forename: Laure
authors.initials: L
authors.lastname: Caspers
authors.affiliation: I.R.I.B.H.M (Institute of Interdisciplinary Research), Université Libre De Bruxelles Campus Erasme, Brussels, Belgium.
authors.forename: Catherine
authors.initials: C
authors.lastname: Bruyns
authors.affiliation: I.R.I.B.H.M (Institute of Interdisciplinary Research), Université Libre De Bruxelles Campus Erasme, Brussels, Belgium; Department of Ophthalmology, CHU St-Pierre and Brugmann, Brussels, Belgium.
authors.forename: François
authors.initials: F
authors.lastname: Willermain
mesh_terms: D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism*; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D007371:Interferon-gamma / Q000378:metabolism; D020381:Interleukin-17 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D000072000:NF-KappaB Inhibitor alpha / Q000378:metabolism; D010766:Phosphorylation; D012333:RNA, Messenger / Q000378:metabolism; D055213:Retinal Pigment Epithelium / Q000378:metabolism*; D050794:STAT1 Transcription Factor; D000071222:Suppressor of Cytokine Signaling 1 Protein / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D014605:Uveitis / Q000378:metabolism*
chemical_list: D016207:Cytokines; D000949:Histocompatibility Antigens Class II; C508717:IL17A protein, human; D020381:Interleukin-17; D016209:Interleukin-8; D012333:RNA, Messenger; C108944:SOCS1 protein, human; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D000071222:Suppressor of Cytokine Signaling 1 Protein; C439524:TNF protein, human; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D000072000:NF-KappaB Inhibitor alpha; D007371:Interferon-gamma
keywords: ,IL-17; IFNγ; IL-8; RPE; SOCS1; UVEITIS