KERATINOCYTE GROWTH-FACTOR ACCELERATES CORNEAL EPITHELIAL WOUND-HEALING IN-VIVO

Purpose. To examine whether the topical application of keratinocyte gr owth factor (KGF) can enhance corneal epithelial healing in vivo. In a ddition, the distribution of S-phase cells in KGF-treated and control corneas was investigated during regeneration and under normal conditio ns. Methods. A 10-mm diameter epithelial defect was made in the center of rabbit corneas. A 50-mu l aliquot of 10 mu g/ml human keratinocyte growth factor (hKGF) was then applied topically five times a day. The same volume of phosphate-buffered saline (PBS) vehicle was applied to the contralateral eye as a control. Each corneal epithelial defect wa s subsequently photographed every 12 hours and was measured by a compu ter-assisted digitizer. For the S-phase cell analysis, entire corneas were labeled with H-3-thymidine and were subjected to autoradiography at 24 hours after wounding or in the normal cornea at 24 hours after t he application of KGF or PBS. Results. Topical application of 10 mu g/ ml hKGF significantly accelerated corneal epithelial wound healing whe n compared with controls. In the S-phase cell analysis, KGF did not ha ve any effect on normal corneal epithelial cells. However, in the rege nerating cornea, the number of S-phase cells in the KGF-treated limbal epithelium was twofold higher than in the controls. Conclusions. Topi cal application of KGF accelerated corneal epithelial wound healing in vivo and increased cell proliferation in the limbal epithelium of the regenerating cornea.