Transfer of Epithelial Cells From PDMS Contact Lenses to Wounded Corneas

Abstract

Abstract: : Purpose: Persistent epithelial defects such as corneal ulcers and recurrent epithelial defects are serious complications of corneal wound healing disorders. Current evidence suggests epithelial proliferation, adhesion, or migration is compromised in these cases. We hypothesize that the direct application of corneal epithelial cells within the site of injury will promote quicker wound coverage and accelerate healing. Methods: Polydimethylsiloxane (PDMS), a highly O₂ permeable polymer, was used to fabricate smooth unpatterned and 100micron–post micropatterned disks and contacts. We used a well–characterized human corneal epithelial cell line (Araki–Sasaki et al., IOVS 36(3):614, 1995) to initially test cell transfer from PDMS disks onto plastic, matrigel and damaged pig cornea surfaces. Transfer tests were then repeated for the best design using primary cornea cells derived from limbal explants. PDMS disks were seeded with 50,000 cells per cm² (∼50% confluent), and placed cell–side down onto matrigel. The PDMS was removed, and transferred cells on the matrigel were re–suspended and counted after 1, 2 or 3 days of transfer. De–epithelialization of a cornea was induced by alkali burn in an organ culture pig cornea wound model. Transfer from contact lenses to pig corneas was assessed by histological analysis of the corneas at 1, 2 and 3 days. Results: Micropatterned contact lenses delivered 4 times as many cells to a plastic and matrigel recipient surfaces than did smooth unpatterned contact lenses. Microfabricated contact lenses transferred labeled epithelial cells to de–epithelialized pig corneas, providing ∼35% corneal coverage after 2 days and ∼65% after 4 days. Wound model control corneas treated with just a contact lens without cells had epithelial coverage of less than 1%. Primary human and pig corneal epithelial cells derived from limbal explants grew on PDMS contact lenses and were able to transfer to matrigel and wounded pig cornea. Conclusions: Microfabricated PDMS contacts show promise as a cell transfer vehicle to deliver primary corneal epithelial cells to speed healing in damaged corneas.

Keywords: cornea: epithelium • contact lens • wound healing