title: Non-invasive collection and examination of human corneal epithelial cells.
abstract: OBJECTIVE
  To report the development of a new apparatus for non-invasive collection of human corneal epithelial cells.
  
  
  METHODS
  Previous methods of non-invasive, irrigative corneal cell collection resulted in low cell yields limiting potential analysis. A new ocular surface cell collection apparatus (OSCCA) was designed to collect more epithelial cells from direct irrigation of the corneal surface to allow for clinical comparisons. Forty-five samples were obtained (unilateral or bilateral over seven visits) from five human participants. Cell yield, size, phenotype, and corneal staining (prior and post eye wash) were examined.
  
  
  RESULTS
  On average 364 ± 230 epithelial cells were collected from the cornea per eye. Epithelial cell sizes ranged from 8.21 to 51.69 μm in diameter, and 67.30 to 2098.85 μm area. The proportion of corneal specific cells collected per sample was 75 ± 14% as determined by positive K3 expression with AE5. On average, 77 ± 0.2% of epithelial cells harvested were nucleated, the remainder were non-nucleated ghost cells. Corneal staining was reduced in the OSCCA-washed vs. contralateral non-washed eyes (p = 0.02).
  
  
  CONCLUSIONS
  The OSCCA allows collection of human corneal epithelial cells with significantly higher yields, and greater specificity than previously reported. Reduced corneal staining observed post eye-wash demonstrated the safety of the technique, and its ability to remove cells directly from the corneal surface. The OSCCA could provide an objective non-invasive method of investigating pathological changes, effects of topical therapeutics, and impact of contact lenses and care-solutions of the cells of the ocular surface.
authors: Centre for Contact Lens Research, School of Optometry, University of Waterloo, Waterloo, Ontario, Canada. r.peterson@brienholdenvision.org
authors: Rachael Claire
authors: RC
authors: Peterson
authors: Maud
authors: M
authors: Gorbet
authors: Daniel
authors: D
authors: Cira
authors: Christopher
authors: C
authors: Amos
authors: Craig A
authors: CA
authors: Woods
authors: Desmond
authors: D
authors: Fonn
mesh_terms: D000328:Adult; D016039:Corneal Transplantation; D019573:Epithelium, Corneal / Q000166:cytology*; D005260:Female; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D012016:Reference Values; D015203:Reproducibility of Results; D020858:Tissue and Organ Harvesting / Q000379:methods*