title: Expression of neurotrophic factors in cultured human retinal pigment epithelial cells.
abstract: OBJECTIVE
  To see if cultured human retinal pigment epithelial (RPE) cells have the capacity to synthesize neurotrophins, including nerve growth factor (NGF), brain-derived growth factor (BDNF), and neurotrophin-3 (NT-3).
  
  
  METHODS
  Expression of mRNAs for the neurotrophins was studied by the reverse transcription polymerase chain reaction (PCR) method. Quantitative analysis of the gene expression was done by using a semiquantitative PCR method. Secretion of NGF-like immunoreactivity (NGF-LI) into the culture medium was analyzed by enzyme immunoassay (EIA).
  
  
  RESULTS
  Cultured human RPE cells were found to express mRNAs for NGF, BDNF and NT-3. In the conditioned culture medium of the human RPE, 9.44 +/- 0.62 pg/ml (mean +/- SEM, n = 6) NGF-LI was found. Pretreatment of human RPE cells with interleukin-l (IL-1) (20 ng/ml), phorbol myristate acetate (PMA) (100 ng/ml) or tumor necrosis factor-alpha (TNF-alpha) (40 ng/ml) was found to increase the mRNA expression of neurotrophins and also to increase secretion of NGF-LI into the culture medium.
  
  
  CONCLUSIONS
  Our data demonstrate that cultured human RPE cells have the capacity to synthesize neurotrophins, and that various stimulations can up-regulate gene and protein expression of NGF by these cells.
authors.affiliation: Department of Ophthalmology and Visual Science, Kyoto University Graduate School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ishida
authors.forename: N
authors.initials: N
authors.lastname: Yoshimura
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: Y
authors.initials: Y
authors.lastname: Honda
authors.forename: K
authors.initials: K
authors.lastname: Murase
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
mesh_terms: D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics; D002478:Cells, Cultured; D005333:Fetus; D015870:Gene Expression; D006801:Humans; D007124:Immunoenzyme Techniques; D009414:Nerve Growth Factors / Q000235:genetics / Q000378:metabolism*; D020933:Neurotrophin 3; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000378:metabolism*
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D020933:Neurotrophin 3