title: High intravitreal TGF-β1 and MMP-9 levels in eyes with retinal vein occlusion.
abstract: OBJECTIVE
  Vascular endothelial growth factor is a leading target to reduce macular oedema and improve visual acuity in patients with retinal vein occlusion (RVO), whereas the role of vascular destabilizing and fibroproliferative transforming growth factor (TGF)-β1 and matrix metalloproteinases (MMP)-2 and -9 in pathological manifestations of RVO is anticipated but less studied.
  
  
  METHODS
  Undiluted vitreous samples were collected from three central RVO and one branch RVO eyes, all with neovascularization and fibrosis-related sight-threatening complications of RVO. Undiluted vitreous samples of 40 eyes operated due to non-ischemic condition either macular hole or pucker were used as controls. Growth factor and protease concentrations were measured by ELISA and gelatin zymography.
  
  
  RESULTS
  Vitreous concentrations of TGF-β1 (92.0 ± 17.4 pg/ml vs 18.3 ± 27.0 pg/ml, mean ± SD; P=0.002) and MMP-9 (847.9 ± 1196.4 AU/ml vs 87.7 ± 174.0 AU/ml; P=0.010) were higher in the eyes with ischemic RVO than in the controls.
  
  
  CONCLUSIONS
  High intravitreal levels of TGF-β1 and MMP-9 are found in RVO eyes having neovascular and fibrosis manifestation. Further studies are warranted to elucidate whether targeting TGF-β1 and MMP-9 could be beneficial in patients with ischemic RVO.
authors.affiliation: Department of Ophthalmology, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland.
authors.forename: R
authors.initials: R
authors.lastname: Tuuminen
authors.affiliation: Unit of Vitreoretinal Surgery, Department of Ophthalmology, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: S
authors.initials: S
authors.lastname: Loukovaara
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D008875:Middle Aged; D011446:Prospective Studies; D015861:Retinal Neovascularization / Q000378:metabolism / Q000601:surgery; D012170:Retinal Vein Occlusion / Q000378:metabolism* / Q000601:surgery; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*; D014821:Vitrectomy; D014822:Vitreous Body / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D053773:Transforming Growth Factor beta1; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9