J Korean Ophthalmol Soc.  2003 Oct;44(10):2342-2352.

The Effect of the Corneal Epithelium on the Keratocyte Apoptosis

• Lee TS
• Hong JW
• Ahn JB

Abstract

PURPOSE
Keratomileusis was performed in rabbits to investigate the effects of corneal epithelium on the corneal stromal keratocyte apoptosis and the effect of human IL-1alpha and TNFalpha on apoptotic genes in human corneal stromal cells was evaluated. METHODS: Fifty six New Zealand white rabbits underwent corneal flap procedure and corneal epithelium was inserted between the corneal flap and underlying stroma. Keratocyte apoptosis was detected with the TUNEL assay. Gene array technique was used to evaluate changes in apoptosis gene in human stromal fibroblasts in response to human recombinant IL-1alpha and TNFalpha in vitro.
RESULTS
Keratocyte apoptosis was significantly greater in group for flap with insertion of peripheral epithelium at 4 hours after surgery(p=0.0249). IL-1alpha or TNFalpha regulated the expression of several genes (insulin like growth factor, stress activated protein kinase, GTP binding protein, IGFBP4) up and down in human stromal fibroblasts in culture.
CONCLUSIONS
We think that the differences in the stromal cell apoptosis after keratomileusis were due to stromal cell response to various factors of inserted corneal epithelium. We found various new apoptosis gene expression in cultured human keratocytes mediated by IL-1alpha and TNFalpha that were secreted in corneal epithelium. These genes likely trigger the apoptosis of keratocyte following epithelial insertion associated with corneal surgery.

Keyword

Apoptosis; Atlas array; LASIK

MeSH Terms

Apoptosis*
Epithelium
Epithelium, Corneal*
Fibroblasts
Gene Expression
GTP-Binding Proteins
Humans
In Situ Nick-End Labeling
Keratomileusis, Laser In Situ
Protein Kinases
Rabbits
Stromal Cells
Tumor Necrosis Factor-alpha
GTP-Binding Proteins
Protein Kinases
Tumor Necrosis Factor-alpha