title: Vitreous levels of pigment epithelium-derived factor and vascular endothelial growth factor: implications for ocular angiogenesis.
abstract: OBJECTIVE
  Pigment epithelium-derived factor (PEDF) has been demonstrated to suppress ocular angiogenesis in several animal models. In this study, we sought to measure the levels of PEDF and vascular endothelial growth factor (VEGF) in the vitreous of patients with and without ocular neovascular disorders.
  
  
  METHODS
  Case-control study of patients undergoing intraocular surgery for a variety of neovascular and nonneovascular conditions.
  
  
  METHODS
  Vitreous samples were collected from 65 eyes of 65 patients with no neovascular disorder (n = 24), choroidal neovascularization (n = 9), active proliferative diabetic retinopathy (n = 16), and inactive proliferative diabetic retinopathy (n = 16). The levels of VEGF and PEDF in these vitreous samples were determined by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  The VEGF levels were at or below the level of detectability in the reference and choroidal neovascularization groups. The VEGF levels were significantly elevated in both the active and inactive PDR groups, and significantly higher in the active PDR group as compared with the inactive PDR group. The PEDF levels, which were present at relatively high concentrations in all groups, were higher in patients with active PDR compared with the control and choroidal neovascularization groups.
  
  
  CONCLUSIONS
  High levels of immunoreactive PEDF are present in the vitreous of individuals with or without ocular neovascularization, but PEDF levels are significantly higher in patients with active PDR compared with patients with choroidal neovascularization or nonneovascular retinal diseases. Although these results do not preclude the possibility that endogenous PEDF helps to modulate ocular neovascularization, they do not support ischemia-induced downregulation of PEDF as a mechanism for such modulation.
authors.affiliation: Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA. eduh@jhmi.edu
authors.forename: Elia J
authors.initials: EJ
authors.lastname: Duh
authors.forename: Hoseong S
authors.initials: HS
authors.lastname: Yang
authors.forename: Julia A
authors.initials: JA
authors.lastname: Haller
authors.forename: Eugene
authors.initials: E
authors.lastname: De Juan
authors.forename: Mark S
authors.initials: MS
authors.lastname: Humayun
authors.forename: Peter
authors.initials: P
authors.lastname: Gehlbach
authors.forename: Michele
authors.initials: M
authors.lastname: Melia
authors.forename: Dante
authors.initials: D
authors.lastname: Pieramici
authors.forename: J B
authors.initials: JB
authors.lastname: Harlan
authors.forename: Peter A
authors.initials: PA
authors.lastname: Campochiaro
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Zack
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D016022:Case-Control Studies; D020256:Choroidal Neovascularization / Q000175:diagnosis / Q000378:metabolism*; D003930:Diabetic Retinopathy / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005136:Eye Proteins / Q000378:metabolism; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D008297:Male; D008875:Middle Aged; D009414:Nerve Growth Factors; D011506:Proteins / Q000378:metabolism*; D015843:Serpins / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D014822:Vitreous Body / Q000378:metabolism*; D000099174:Pigment Epithelium-Derived Factor
chemical_list: D005136:Eye Proteins; D009414:Nerve Growth Factors; D011506:Proteins; D015843:Serpins; D042461:Vascular Endothelial Growth Factor A; D000099174:Pigment Epithelium-Derived Factor