title: Vitronectin: a matrix support factor for human limbal epithelial progenitor cells.
abstract: OBJECTIVE
  The authors recently developed a therapeutic technique for patients with limbal stem cell deficiency by harvesting ocular surface stem cells (SCs), expanding them on therapeutic contact lenses (CLs), and applying them to diseased corneas. The present study determined the proteins that bind to CLs and whether such factors, along with transplanted cells, are critical determinants for corneal rehabilitation using this method.
  
  
  METHODS
  Therapeutic CLs were exposed to human serum, and adherent proteins were analyzed by proteomics. The distribution of vitronectin (VN) on the ocular surface was determined with specific antibodies. Cadaveric human corneas were chemically wounded, and cell transfer by CLs was assessed in organ culture.
  
  
  RESULTS
  VN was identified as a serum factor that binds and desorbs from CLs. VN localized to the limbal and basement membranes (BM) of other SC-harboring organs. Clonogenic assays demonstrated higher colony-forming efficiency on VN compared with uncoated surfaces. Cell transfer from CLs was achieved through in vitro models and was abrogated by RGD peptides and inhibitory antibodies to VN and its receptor.
  
  
  CONCLUSIONS
  Identification of VN within the limbal BM, its effect on limbal SC activity, and the discovery of this factor on serum-exposed CL polymers implies a role in supporting progenitor cells and facilitating corneal regeneration.
authors: Inflammation and Infection Research Centre, School of Medical Sciences, University of New South Wales, Sydney, Australia.
authors: Timothy Jerome
authors: TJ
authors: Echevarria
authors: Sharron
authors: S
authors: Chow
authors: Stephanie
authors: S
authors: Watson
authors: Denis
authors: D
authors: Wakefield
authors: Nick
authors: N
authors: Di Girolamo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D002448:Cell Adhesion / Q000502:physiology; D018929:Cell Culture Techniques; D003261:Contact Lenses; D004591:Electrophoresis, Polyacrylamide Gel; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000502:physiology*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D016850:Limbus Corneae / Q000166:cytology / Q000378:metabolism*; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D010865:Pilot Projects; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D019096:Vitronectin / Q000502:physiology*
chemical_list: D016326:Extracellular Matrix Proteins; D019096:Vitronectin