title: Effect of proinflammatory cytokines on the human MUC5AC promoter activity in vitro and in vivo.
abstract: OBJECTIVE
  To investigate the effect of inflammatory cytokines on the activity of the human MUC5AC promoter in vitro and in vivo.
  
  
  METHODS
  Conjunctival epithelial cells transfected with MUC5AC-luciferase plasmids challenged with different cytokines (tumor necrosis factor-alpha [TNF-alpha], interleukin [IL]-1beta, IL-2, IL-6, and IL-8) at various concentration (1, 10, 20, 50, 100, 200, 500, 1000, and 2000 pg/mL) for 24 hours. A Helio Gene Gun system (Bio-Rad Laboratories, Hercules, CA, USA) was used to deliver MUC5AC-luciferase plasmids into rabbit conjunctivas, which were also challenged with these cytokines (1000 pg/mL) at the frequency of every six hours for 48 hours. The activity of MUC5AC-luciferase was then evaluated using the luciferase assay.
  
  
  RESULTS
  Results of the studies demonstrated that IL-1beta and TNF-alpha upregulated the activity of MUC5AC-luciferase in cultured conjunctival cells, while IL-2, IL-6, and IL-8 had no effect. In rabbit conjunctival tissues, TNF-alpha, IL-1beta, IL-2, IL-8, and IL-6 significantly upregulated MUC5AC gene expression.
  
  
  CONCLUSIONS
  This suggests that MUC5AC mucin gene expression is regulated by proinflammatory cytokines, which could have implications in ocular surface disorders.
authors: Department of Ophthalmology, National Taiwan University Hospital, 7, Chung-Shan South Road, Taipei, Taiwan. ijong@ha.mc.ntu.edu.tw
authors: I-Jong
authors: IJ
authors: Wang
authors: Chun-Yin
authors: CY
authors: Wu
authors: Fung-Rong
authors: FR
authors: Hu