title: EphB4 expression in pterygium is associated with microvessel density.
abstract: OBJECTIVE
  Angiogenesis is a key component of the pathogenesis process of pterygium, which is the growth of fibrovascular tissue on the cornea. It has been reported that EphB4, a receptor tyrosine kinase of the ephrin-Eph system, plays important role in vascular development during embryogenesis and tumor angiogenesis and is potentially involved in ocular angiogenesis. The aim of this study is to investigate the role of EphB4 in pterygia.
  
  
  METHODS
  Fifteen pterygium samples and their paired upper bulbar conjunctiva were evaluated for expression of EphB4 and CD31 by using immunohistochemical staining. The expression level of the mRNA of EphB4 gene in 7 pterygia and matched upper bulbar conjunctiva was evaluated by using a quantitative real-time RT-PCR analysis. Microvessel density (MVD) was assessed with antibody that targets CD31.
  
  
  RESULTS
  EphB4 protein was high expressed in the epithelium and stroma of pterygia compared to those in upper bulbar conjunctiva. Immunohistochemical staining showed that pterygia presented with statistically significant higher average count of microvessel compared to normal conjunctivae (28.24 ± 6.79 vs 11.09 ± 2.96 per high power field, P < 0.001). MVD values in stroma of the pterygium and normal conjunctiva presented a significant correlation with EphB4 staining (P < 0.001). Compared with autologous upper bulbar conjunctiva grafts, the expression of the EphB4 mRNA was increased in pterygia in 4 paired samples, including those 3 recurrent ones.
  
  
  CONCLUSIONS
  The expression of EphB4 in pterygium was significantly related with the increased MVD and may be involved in angiogenesis. EphB4 protein is a potential target for treatment of pterygium.
authors.affiliation: Department of Ophthalmology, Jinling Hospital, Nanjing University School of Medicine Nanjing 210002, P. R. China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Xue
authors.affiliation: Department of Ophthalmology, Jinling Hospital, Nanjing University School of Medicine Nanjing 210002, P. R. China.
authors.forename: Yueqin
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, Jinling Hospital, Nanjing University School of Medicine Nanjing 210002, P. R. China.
authors.forename: Zhenping
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Ophthalmology, Jinling Hospital, Nanjing University School of Medicine Nanjing 210002, P. R. China.
authors.forename: Yirui
authors.initials: Y
authors.lastname: Ge
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine Nanjing 210002, P. R. China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Pathology, Jinling Hospital, Nanjing University School of Medicine Nanjing 210002, P. R. China.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Wang
keywords: EphB4; MVD; Pterygium; angiogenesis