[Mechanism of keratinocyte growth factor-2 accelerating corneal epithelial wound healing on rabbit alkali burned cornea].
OBJECTIVE
To evaluate the curative effect of KGF-2 on the alkali-injured rabbit eye and to investigate the mechanism of KGF-2 accelerating corneal epithelial wound healing.


METHODS
Alkali burn was produced in 24 corneas from 24 New Zealand rabbits. Four groups were randomly divided. Three groups (A, B, and C groups) were treated with KGF-2 solution (1, 50, 100 microg/ml, respectively), and one group (D group) was treated with phosphate-buffered saline (PBS) solution. The injured eyes were photographed after the fluorescence staining with a slit lamp and the pictures were analyzed with computer-aided picture analysis system to calculate the rate of corneal epithelial healing. Morphologic and immunohistological examinations (using P63, AE5 and EGFR antibodies) of the cornea were performed.


RESULTS
KGF-2 at dosages ranging from 1 microg/ml to 100 microg/ml could enhance the cornea wound healing process. After 24 hours, epithelial healing rate of the 100 microg/ml KGF-2 group and the PBS treated group was 74% and 40%, respectively (P < 0.05). The corneal epithelial healing rate of each group was variable after four days and achieved complete healing after ten days. The P63 positive cells in KGF-2 groups appeared not only in the limbal area but also in the central area. For example, on the seventh day, in the limbal area, the P63 positive cells in the 100 microg/ml KGF-2 group, the PBS treated group and the normal group were 53.8 +/- 2.6, 29.5 +/- 2.2 and 17.0 +/- 2.1, respectively (P = 0.000). At the same time, the P63 positive cells in the non-limbal area in the 100 microg/ml KGF-2 group, the PBS treated group and the normal group were 69.5 +/- 2.8, 19.5 +/- 2.8 and 0, respectively (P = 0.000).


CONCLUSIONS
These results suggested KGF-2 can stimulate the limbal epithelial stem cells to migrate to the central cornea. KGF-2 can accelerate the healing of alkali burned cornea.
Liu
Lin
L
Zhongshan Ophthalmic Center, Zhongshan University, Guangzhou 510060, China.
Li
Yong-Ping
YP
Huang
Shu-Qi
SQ
Lin
Jian-Xian
JX
Zhang
Wen-Xin
WX
D000468:Alkalies / Q000009:adverse effects; D000818:Animals; D002057:Burns, Chemical / Q000188:drug therapy*; D003315:Cornea / Q000473:pathology; D065306:Corneal Injuries; D019573:Epithelium, Corneal / Q000166:cytology / Q000187:drug effects*; D005126:Eye Burns / Q000139:chemically induced / Q000188:drug therapy*; D005260:Female; D051526:Fibroblast Growth Factor 10 / Q000494:pharmacology*; D008297:Male; D011817:Rabbits; D014945:Wound Healing / Q000187:drug effects
D000468:Alkalies; D051526:Fibroblast Growth Factor 10