title: Decreased microRNA-155 expression in ocular Behcet's disease but not in Vogt Koyanagi Harada syndrome.
abstract: OBJECTIVE
  MicroRNAs (miRNAs) have emerged as a class of gene expression regulators involved in immune regulation. In the present study, we investigated the role of miRNA in two uveitis entities: Behcet's disease (BD) and Vogt Koyanagi Harada syndrome (VKH).
  
  
  METHODS
  The expression of five miRNAs was studied in PBMCs, DCs, and CD4(+) T cells from BD patients with active and inactive uveitis, VKH patients with active uveitis, and healthy controls using real-time PCR. MiR-155 mimics and inhibitor were transfected to DCs to evaluate the effect on DC maturation and cytokine production by these cells and CD4(+) T cells. Luciferase reporter assays and Western blotting were performed to identify the target gene of miR-155.
  
  
  RESULTS
  Only miR-155 expression was significantly decreased in PBMCs and DCs from BD patients with active uveitis and no differences were observed in the miRNA expression in cells from patients with VKH as compared with controls. Overexpression of miR-155 in DCs was shown to inhibit the production of IL-6 and IL-1β, and to promote the expression of IL-10 by these cells. MiR-155 transfected DCs significantly inhibited intracellular IL-17 expression in allogeneic CD4(+) T cells; however, it did not influence the expression of cell surface markers CD80, CD40, CD83, CD86, and HLA-DR. Luciferase reporter assays revealed that TAB2 was a target gene of miR-155, which was confirmed by Western blotting.
  
  
  CONCLUSIONS
  The present results suggest that miR-155 expression is decreased in active BD but not in VKH patients. Downregulated miR-155 may be involved in BD pathogenesis by targeting TAB2.
authors: The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology, and Chongqing Eye Institute, Chongqing, PR China.
authors: Qingyun
authors: Q
authors: Zhou
authors: Xiang
authors: X
authors: Xiao
authors: Chaokui
authors: C
authors: Wang
authors: Xuedong
authors: X
authors: Zhang
authors: Fuzhen
authors: F
authors: Li
authors: Yan
authors: Y
authors: Zhou
authors: Aize
authors: A
authors: Kijlstra
authors: Peizeng
authors: P
authors: Yang
mesh_terms: D000208:Acute Disease; D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D001528:Behcet Syndrome / Q000235:genetics* / Q000503:physiopathology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000378:metabolism; D002478:Cells, Cultured; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000166:cytology / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D016753:Interleukin-10 / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D035683:MicroRNAs / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D014605:Uveitis / Q000235:genetics* / Q000503:physiopathology; D014607:Uveomeningoencephalitic Syndrome / Q000235:genetics* / Q000503:physiopathology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C508609:IL10 protein, human; C508600:IL6 protein, human; D053583:Interleukin-1beta; D015850:Interleukin-6; C542542:MIRN146 microRNA, human; C524942:MIRN155 microRNA, human; C524941:MIRN17 microRNA, human; C545322:MIRN326 microRNA, human; C540193:MIrn181 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; C410585:TAB2 protein, human; D016753:Interleukin-10