TGF-beta and IL-1 beta act in synergy to enhance IL-6 and IL-8 mRNA levels and IL-6 production by human retinal pigment epithelial cells

Immunology. 1995 Feb;84(2):265-71.


Cytokines produced by human retinal pigment epithelial (RPE) cells may function as important regulators of intraocular inflammation. We investigated the effect of transforming growth factor-beta (TGF-beta) on interleukin-1 beta (IL-1 beta) induction of IL-6 and IL-8 mRNA levels and protein production by human RPE cells. Both TGF-beta and IL-1 beta alone induce IL-6 mRNA and IL-6 production in human RPE cells and synergize to enhance IL-6 mRNA levels and IL-6 production over a range of TGF-beta (0.1-10 ng/ml) and IL-1 beta concentrations (5-500 U/ml). TGF-beta was also found to enhance IL-1 beta induction of IL-8 mRNA levels at lower IL-1 beta concentrations (50 U/ml) but had no effect at higher IL-1 beta concentrations (500 U/ml). However, TGF-beta had no synergistic effect on IL-1 beta induction of IL-8 secretion. These results suggest that expression of IL-6 and IL-8 in human RPE cells is regulated by different transcriptional and translational mechanisms, and that RPE cells are important regulators of cytokine production within the ocular microenvironment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Blotting, Northern
  • Cells, Cultured
  • Drug Synergism
  • Humans
  • Interleukin-1 / metabolism*
  • Interleukin-1 / pharmacology
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism*
  • Interleukin-8 / genetics
  • Interleukin-8 / metabolism*
  • Middle Aged
  • Pigment Epithelium of Eye / cytology
  • Pigment Epithelium of Eye / metabolism*
  • RNA, Messenger / analysis
  • RNA, Messenger / metabolism
  • Transforming Growth Factor beta / metabolism*
  • Transforming Growth Factor beta / pharmacology


  • Interleukin-1
  • Interleukin-6
  • Interleukin-8
  • RNA, Messenger
  • Transforming Growth Factor beta