title: Effects of amniotic membrane extract on primary human corneal epithelial and limbal cells.
abstract: BACKGROUND
  To assess the effects of amniotic membrane extract (AMX) on cellular activity of primary human corneal epithelial (HCE) cells under mechanical and oxidative stress, and on human limbal cells under oxidative stress.
  
  
  METHODS
  Corneal mechanical stress was simulated with a linear scratch in confluent HCE cell plates, then incubated with 0.1% AMX for 48 and 72 h. Subjecting HCE cultures to 0.5 mmol/L tertiary-butylhydroperoxide for 1 h simulated an oxidative stress. 0.1% AMX-treated cultures were compared with controls at 24 and 48 h using cellular viability assay, along with 12-h AMX pretreatment and human limbal cell comparisons.
  
  
  RESULTS
  Mechanical stress on HCE cultures revealed a statistically significant distance ratio at 48 and 72 h in favour of 0.1% AMX-treated cultures (P = 0.021 and 0.035, respectively). Oxidative stress did not reveal any significant difference in cellular viability of AMX-treated versus control cultures. Twelve hour AMX pre-treatment prior to oxidative stress revealed a significant difference after 24 h from oxidative injury (73.3% AMX vs. 66.0% control, P = 0.035), but not after 48 h. Human limbal cells demonstrated significantly improved oxidative viability compared with HCE cells, with (91.0% vs. 82.0% control, P = 0.017) and without 0.1% AMX pre-treatment (91.2% vs. 83.7% control, P = 0.019).
  
  
  CONCLUSIONS
  HCE cells treated with AMX healed faster after mechanical insult, suggesting a potential benefit in acute corneal injuries. Under oxidative stress, human limbal cells, a more proliferative cell type, showed superior viability compared with HCE cells.
authors.affiliation: Ivey Eye Institute, Western University, London, Ontario, Canada.
authors.forename: David V
authors.initials: DV
authors.lastname: Dudok
authors.affiliation: Ivey Eye Institute, Western University, London, Ontario, Canada.
authors.forename: Imraan
authors.initials: I
authors.lastname: Nagdee
authors.affiliation: Ivey Eye Institute, Western University, London, Ontario, Canada.
authors.forename: Kevin
authors.initials: K
authors.lastname: Cheung
authors.affiliation: Ivey Eye Institute, Western University, London, Ontario, Canada.
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.affiliation: Division of Nephrology, Cell Biology, Human Biology and Physiology, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors.forename: Luca
authors.initials: L
authors.lastname: Vedovelli
authors.affiliation: Harvard Medical School, Schepens Eye Research Institute, Boston, Massachusetts, USA.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Ghinelli
authors.affiliation: Harvard Medical School, Schepens Eye Research Institute, Boston, Massachusetts, USA.|New England Medical Center, Tufts University, Boston, Massachusetts, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Kenyon
authors.affiliation: Ivey Eye Institute, Western University, London, Ontario, Canada.
authors.forename: Sunil
authors.initials: S
authors.lastname: Parapuram
authors.affiliation: Ivey Eye Institute, Western University, London, Ontario, Canada.
authors.forename: Cindy M
authors.initials: CM
authors.lastname: Hutnik
mesh_terms: D000650:Amnion / Q000737:chemistry*; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival; D019573:Epithelium, Corneal / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D016850:Limbus Corneae / Q000166:cytology / Q000187:drug effects*; D018384:Oxidative Stress; D013314:Stress, Mechanical; D014020:Tissue Extracts / Q000494:pharmacology*; D014945:Wound Healing / Q000502:physiology; D020122:tert-Butylhydroperoxide / Q000633:toxicity
chemical_list: D014020:Tissue Extracts; D020122:tert-Butylhydroperoxide
keywords: Amniotic membrane; Cornea; Corneal wound healing