title: Vitreous and serum levels of platelet-derived growth factor and their correlation in patients with proliferative diabetic retinopathy.
abstract: OBJECTIVE
  We investigated possible correlations between vitreous and/or serum levels of platelet derived growth factor isoforms (PDGF-AA, -AB, -BB) with parameters associated with proliferative diabetic retinopathy (PDR), and compared the results to vascular endothelial growth factor (VEGF), which is an established growth factor affecting PDR.
  
  
  METHODS
  Thirty-one patients with PDR and 15 non-diabetic patients were included in the study. Vitreous and serum samples were obtained during vitrectomy. PDGF-AA, -AB, and -BB, as well as VEGF, were measured by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  PDGF-AA, -AB, -BB, and VEGF were all expressed in serum and vitreous of controls and patients with PDR. The levels of all PDGF isoforms and VEGF in vitreous were significantly increased in the PDR group, as compared to controls. No such differences were evident in serum. PDGF-AA and PDGF-BB correlated significantly to the severity but not the activity of PDR. PDGF-AB and -BB were significantly lower in vitreous of patients with pre-performed complete panretinal photocoagulation (PRP) as compared to incomplete or without PRP. PDGF did not correlate significantly to fibrovascular tissue, on the disc or elsewhere, to long-standing vitreous hemorrhage, to tractional retinal detachment, or to posterior vitreous detachment. PDGF or VEGF in vitreous or serum of PDR patients did not correlate with the serum levels of HbA1C. There was no correlation between the vitreous and serum levels of VEGF or PDGF in patients with PDR.
  
  
  CONCLUSIONS
  It appears that, in addition to VEGF, PDGF-AA, -AB, and -BB in the vitreous are also correlated with PDR.
authors.affiliation: 2nd Department of Ophthalmology, Aristotle University of Thessaloniki, Thessaloniki, Greece. praidou2003@yahoo.co.uk
authors.forename: Anna
authors.initials: A
authors.lastname: Praidou
authors.forename: Ioannis
authors.initials: I
authors.lastname: Klangas
authors.forename: Eleni
authors.initials: E
authors.lastname: Papakonstantinou
authors.forename: Sofia
authors.initials: S
authors.lastname: Androudi
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Georgiadis
authors.forename: George
authors.initials: G
authors.lastname: Karakiulakis
authors.forename: Stavros
authors.initials: S
authors.lastname: Dimitrakos
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D003930:Diabetic Retinopathy / Q000150:complications / Q000175:diagnosis / Q000378:metabolism*; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D033401:Microscopy, Acoustic; D010982:Platelet-Derived Growth Factor / Q000378:metabolism*; D011379:Prognosis; D012160:Retina / Q000000981:diagnostic imaging / Q000473:pathology; D012189:Retrospective Studies; D013054:Spectrophotometry, Atomic; D018630:Vitreoretinopathy, Proliferative / Q000150:complications / Q000175:diagnosis / Q000378:metabolism*; D014822:Vitreous Body / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology
chemical_list: D015415:Biomarkers; D010982:Platelet-Derived Growth Factor