title: In Vitro Model for Predicting the Protective Effect of Ultraviolet-Blocking Contact Lens in Human Corneal Epithelial Cells.
abstract: OBJECTIVE
  To develop an in vitro method to determine the protective effect of UV-blocking contact lenses (CLs) in human corneal epithelial (HCE) cells exposed to UV-B radiation.
  
  
  METHODS
  SV-40-transformed HCE cells were covered with non-UV-blocking CL, UV-blocking CL or not covered, and exposed to UV-B radiation. As control, HCE cells were covered with both types of CLs or not covered, but not exposed to UV-B radiation. Cell viability at 24, 48 and 72 h, after UV-B exposure and removing CLs, was determined by alamarBlue(®) assay. Percentage of live, dead and apoptotic cells was also assessed by flow cytometry after 24 h of UV-B exposure. Intracellular reactive oxygen species (ROS) production after 1 h of exposure was assessed using the dye H(2)DCF-DA.
  
  
  RESULTS
  Cell viability significantly decreased, apoptotic cells and intracellular ROS production significantly increased when UVB-exposed cells were covered with non-UV-blocking CL or not covered compared to non-irradiated cells. When cells were covered with UV-blocking CL, cell viability significantly increased and apoptotic cells and intracellular ROS production did not increase compared to exposed cells.
  
  
  CONCLUSIONS
  UV-B radiation induces cell death by apoptosis, increases ROS production and decreases viable cells. UV-blocking CL is able to avoid these effects increasing cell viability and protecting HCE cells from apoptosis and ROS production induced by UV-B radiation. This in vitro model is an alternative to in vivo methods to determine the protective effect of UV-blocking ophthalmic biomaterials because it is a quicker, cheaper and reliable model that avoids the use of animals.
authors.affiliation: Instituto de Oftalmobiología Aplicada (IOBA), Universidad de Valladolid , Valladolid , Spain , and.
authors.forename: Antonio
authors.initials: A
authors.lastname: Abengózar-Vela
authors.forename: Cristina
authors.initials: C
authors.lastname: Arroyo
authors.forename: Roberto
authors.initials: R
authors.lastname: Reinoso
authors.forename: Amalia
authors.initials: A
authors.lastname: Enríquez-de-Salamanca
authors.forename: Alfredo
authors.initials: A
authors.lastname: Corell
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: González-García
mesh_terms: D017209:Apoptosis / Q000528:radiation effects; D001681:Biological Assay; D002452:Cell Count; D002461:Cell Line, Transformed; D002470:Cell Survival; D003263:Contact Lenses, Hydrophilic; D019573:Epithelium, Corneal / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D005434:Flow Cytometry; D006801:Humans; D011832:Radiation Injuries / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods; D017382:Reactive Oxygen Species / Q000378:metabolism; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D017382:Reactive Oxygen Species
keywords: Apoptosis; contact lens; corneal epithelial cells; oxidative stress; ultraviolet light