title: Effect of retinoic acid on expression of transforming growth factor-beta by retinal pigment epithelial cells in culture.
abstract: OBJECTIVE
  To study the effect of retinoic acid on the expression of transforming growth factor-beta (TGF-beta) by human retinal pigment epithelial (RPE) cells in culture.
  
  
  METHODS
  Expression of TGF-beta 1 by RPE cells after 24 hours in culture at the messenger RNA level (Northern analysis) and the protein level (enzyme-linked immunosorbent assay [ELISA]).
  
  
  RESULTS
  On the basis of cell morphology, growth characteristics and the results of immunohistochemical studies, we concluded that the cells used in these experiments were RPE in origin. Immunohistochemical studies confirmed TGF-beta 1 expression by the RPE cells in culture. Densitometry showed that retinoic acid reduced the level of TGF-beta 1 mRNA expression by 41% compared with control samples. ELISA showed that retinoic acid inhibited TGF-beta expression when compared with the baseline level of TGF-beta in media from RPE cells in culture.
  
  
  CONCLUSIONS
  These findings may have implications for the pharmacotherapy of proliferative vitreoretinopathy.
authors.affiliation: Department of Ophthalmology, University of Alberta, Edmonton.
authors.forename: I M
authors.initials: IM
authors.lastname: MacDonald
authors.forename: R
authors.initials: R
authors.lastname: Pannu
authors.forename: K
authors.initials: K
authors.lastname: Kovithavongs
authors.forename: C
authors.initials: C
authors.lastname: Peters
authors.forename: E E
authors.initials: EE
authors.lastname: Tredget
authors.forename: A
authors.initials: A
authors.lastname: Ghahary
mesh_terms: D015152:Blotting, Northern; D002478:Cells, Cultured; D004587:Electrophoresis, Agar Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007124:Immunoenzyme Techniques; D007641:Keratolytic Agents / Q000494:pharmacology*; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis; D016212:Transforming Growth Factor beta / Q000096:biosynthesis* / Q000235:genetics; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D007641:Keratolytic Agents; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D014212:Tretinoin