Abstract
Purpose: :
To investigate the fate of trans-amplifying epithelial cells in the central cornea using a rabbit persistent corneal epithelial defect model created by transplanting a stainless steel ring in the cornea. Using this model, epithelial cells outside the ring failed to migrate inside the ring.
Methods: :
A stainless steel ring (8 mm diameter, 300µm wide and 250µm depth) was transplanted into rabbit corneal stroma using 10-0 nylon interrupted sutures. Subsequently we observed wound healing of epithelial defects created within the ring (4, 5, 6, 8mm diameter) compared with control corneas without ring transplants. After 1 week, hematoxylin staining and phenotype analysis was performed by immunostaining for p63, Ki67, and CK3 in a set of animals. Others were continuously observed with repeated epithelial defect of same diameter until cells exhausted.
Results: :
Corneal stroma with ring transplantation for 1week showed little inflammation. When epithelium was totally removed inside of the ring, the epithelial defect persisted for at least a month. (n=3) Immunostaining showed similar expression of p63, Ki67, and CK3 compared to normal control. Wound healing was observed in smaller defects (4, 5, 6 mm), however, once cells failed to cover the surface after repeated epithelial removal, cells exhausted on the next day in all cases.
Conclusions: :
Trans-amplifying cells may be maintained for more than 1 month when separated from limbal stem cells in vivo. Their fate may depend on replicative senescence, as well as the area required to heal.
Keywords: wound healing • cornea: basic science • cornea: epithelium