title: [Expression of matrix metalloproteinases and inhibitor on the cornea tissue in rabbit after implantation of modified titanium skirt for keratoprosthesis].
abstract: OBJECTIVE
  To investigate the expression of matrix metalloproteinase-2 (MMP-2) and Tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in rabbit corneas implanted with modified titanium skirt of keratoprosthesis in order to explore the potential roles.
  
  
  METHODS
  A total of 20 New Zealand white rabbits with corneal alkali burn in right eye rabbit corneas were divided into three groups. There were 6 animals in each group. Skirt of hydroxyapatite/Sandblast-Titanium and Sandblast-Titanium were inserted into the corneal stroma of rabbits in group A and group B. The group C did not insert skirt as surgical control.2 rabbits were as normal control D group. A total of 20 New Zealand white rabbits were divided into four groups with the same way. The expression of MMP-2 and TIMP-2 was determined by immunohistochemistry at 1 month, 3 months. The expression of MMP-2 and TIMP-2 mRNA level was determined by real time-polymerase chain reaction, and its protein level was determined by western blot. The optical cylinder was implanted to rabbit corneas, which were implanted with modified titanium skirt after 3 months.
  
  
  RESULTS
  There was one case of corneal dissolution being found in group F. MMP-2 and TIMP-2 immunoreactivities were expressed in the normal corneas, predominantly in the corneal epithelium. After injury, immunoreactivities of both MMP-2 and TIMP-2 were increased notably in the healing corneal epithelium, infiltrating inflammatory cells, stromal fibroblasts and in growing vascular endothelial cells. The expression of MMP-2 was lower in group A and E than that in group B and F after 1 month and 3 months (t = 12.05, 2.93, 12.006, 3.781, P < 0.05). The Western blot revealed no significant differences of MMP-2 mRNA between group 3 months and 2 weeks (t = 2.104, P > 0.05); MMP-2 immunoreactivities were absent or lowly expressed predominantly in the corneal epithelium of normal corneas. The expression of MMP-2, TIMP-2 mRNA level was parallel that of protein level.
  
  
  CONCLUSIONS
  The expression of MMP-2 was lower in the corneal tissue sections of HA/SB-Ti skirt inserted eyes than that in the tissue sections of SB-Ti skirt inserted eyes. The studies of MMP-2, TIMP-2 can provide a new way to prevent the incidence of corneal dissolving after surgery for keratoprosthesis.
authors.affiliation: Department of Ophthalmology, the General Hospital of PLA, Beijing 100853, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Dilys
authors.initials: D
authors.lastname: Zhou
authors.forename: Xiu-mei
authors.initials: XM
authors.lastname: Wang
authors.forename: Xiao-ping
authors.initials: XP
authors.lastname: Wang
authors.forename: Fu-zhai
authors.initials: FZ
authors.lastname: Cui
authors.forename: Yu-jie
authors.initials: YJ
authors.lastname: Lu
authors.forename: Yi-fei
authors.initials: YF
authors.lastname: Huang
mesh_terms: D000818:Animals; D003315:Cornea / Q000378:metabolism*; D016039:Corneal Transplantation; D005126:Eye Burns / Q000378:metabolism* / Q000601:surgery; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D011817:Rabbits; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism*; D054457:Tissue Scaffolds; D014025:Titanium
chemical_list: D012333:RNA, Messenger; D019716:Tissue Inhibitor of Metalloproteinase-2; D014025:Titanium; D020778:Matrix Metalloproteinase 2