title: Tenascin-C promotes angiogenesis in fibrovascular membranes in eyes with proliferative diabetic retinopathy.
abstract: OBJECTIVE
  We previously demonstrated that tenascin-C was highly expressed in the fibrovascular membranes (FVMs) of patients with proliferative diabetic retinopathy (PDR). However, its role in the pathogenesis of FVMs has not been determined. The purpose of this study was to investigate what role tenascin-C plays in the formation and angiogenesis of FVMs.
  
  
  METHODS
  The level of tenascin-C was determined by sandwich enzyme-linked immunosorbent assay in the vitreous samples collected from patients with PDR and with a macular hole as control. The locations of tenascin-C, α- smooth muscle actin (SMA), CD34, glial fibrillary acidic protein (GFAP), and integrin αV in the FVMs from PDR patients were determined by immunohistochemistry. We also measured the in vitro expression of the mRNA and protein of tenascin-C in vascular smooth muscle cells (VSMCs) stimulated by interleukin (IL)-13. The effects of tenascin-C on cell proliferation, migration, and tube formation were determined in human retinal endothelial cells (HRECs) in culture.
  
  
  RESULTS
  The mean vitreous levels of tenascin-C were significantly higher in patients with PDR than in patients with a macular hole (p<0.001). Double immunofluorescence analyses of FVMs from PDR patients showed that tenascin-C co-stained FVMs with α-SMA, CD34, and integrin αV but not with GFAP. In addition, IL-13 treatment increased both the expression and secretion of tenascin-C by VSMCs in a dose-dependent manner. Tenascin-C exposure promoted proliferation, migration, and tube formation in HRECs. Tenascin-C neutralizing antibody significantly blocked the tube formation by HRECs exposed to VSMC-IL-13-conditioned medium.
  
  
  CONCLUSIONS
  Our findings suggest that tenascin-C is secreted from VSMCs and promotes angiogenesis in the FVMs associated with PDR.
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yoshida
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yedi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Takahito
authors.initials: T
authors.lastname: Nakama
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Keijiro
authors.initials: K
authors.lastname: Ishikawa
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Arima
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Nakao
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Sassa
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Atsunobu
authors.initials: A
authors.lastname: Takeda
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Hisatomi
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ikeda
authors.affiliation: Department of Ophthalmology, Juntendo University, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Matsuda
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Koh-Hei
authors.initials: KH
authors.lastname: Sonoda
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Ishibashi
mesh_terms: D000199:Actins / Q000378:metabolism; D000368:Aged; D018952:Antigens, CD34 / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003930:Diabetic Retinopathy / Q000378:metabolism* / Q000473:pathology; D004730:Endothelium, Vascular / Q000166:cytology; D004797:Enzyme-Linked Immunosorbent Assay; D019773:Epiretinal Membrane / Q000378:metabolism* / Q000473:pathology; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D015861:Retinal Neovascularization / Q000378:metabolism* / Q000473:pathology; D012167:Retinal Perforations / Q000378:metabolism / Q000473:pathology; D012171:Retinal Vessels / Q000166:cytology; D019063:Tenascin / Q000494:pharmacology / Q000502:physiology*; D014822:Vitreous Body / Q000378:metabolism*
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D018952:Antigens, CD34; D005904:Glial Fibrillary Acidic Protein; D012333:RNA, Messenger; D019063:Tenascin