title: Lactoferrin-loaded contact lenses: eye protection against oxidative stress.
abstract: OBJECTIVE
  Tear fluid contains antioxidative compounds, vitamin C, glutathione, superoxide dismutase, and lactoferrin (LF), which protect the corneal epithelium from the effects of ultraviolet irradiation, direct airflow, and chemical agents. However, these natural defenses against oxidative stress can decrease, favoring the development of anterior eye disorders, such as keratoconus, dry eye, and Sjögren syndrome. LF is an iron-binding glycoprotein, present in mammalian secretions such as tears and milk, endowed with different physiological functions such as antimicrobial, antiviral, and antioxidant activities. In this work, we studied the capability of different soft contact lenses to adsorb and release LF to restore cellular viability in oxidative stress conditions.
  
  
  METHODS
  Three types of contact lenses (filcon V, galyfilcon A, and filcon IB) were loaded with LF and then incubated with TsA or human corneal epithelial primary cells. After oxidative stress induction with 250 μM or 125 μM H2O2, cell viability was evaluated.
  
  
  RESULTS
  Data showed that the highest quantity of LF loaded in contact lenses was between 61 μg (for filcon V) and 39 μg (for filcon IB); the release was between 49% and 100% of protein adsorbed. LF released from contact lenses maintained its antioxidant activity at least for 24 hours and was able to protect human epithelial cells from the detrimental effects of oxidative stress.
  
  
  CONCLUSIONS
  These results demonstrate that LF-loaded contact lenses could represent a new therapeutic approach to treat ocular surface pathologies characterized by high levels of oxidative stress.
authors.affiliation: *Department of Biotechnology and Bioscience, University of Milano-Bicocca, Milan, Italy; and †Department of Materials Science, University of Milano-Bicocca, Milan, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Pastori
authors.forename: Silvia
authors.initials: S
authors.lastname: Tavazzi
authors.forename: Marzia
authors.initials: M
authors.lastname: Lecchi
mesh_terms: D000890:Anti-Infective Agents / Q000008:administration & dosage*; D001059:Apoproteins / Q000008:administration & dosage*; D002460:Cell Line; D002470:Cell Survival; D003263:Contact Lenses, Hydrophilic; D003316:Corneal Diseases / Q000517:prevention & control*; D016503:Drug Delivery Systems; D019573:Epithelium, Corneal / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D007781:Lactoferrin / Q000008:administration & dosage*; D016877:Oxidants / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects*
chemical_list: D000890:Anti-Infective Agents; D001059:Apoproteins; D016877:Oxidants; C039223:apolactoferrin; D006861:Hydrogen Peroxide; D007781:Lactoferrin