Abstract
Purpose::
Laminin-5 (Lm5) is one of the major matrix components of the corneal epithelial basement membrane. Many studies revealed that in vitro, Lm5 promotes cell migration by binding to integrin α3ß1, while it mediates stable adhesion through integrin α6ß4. In vivo, it is demonstrated that Lm5 is over-expressed at the sites of epidermal wounds, implying a potential therapeutic effect of Lm5 for the corneal wound healing process. The objective of this study is to examine the effect of topically applied Lm5 on a corneal epithelial wound with a rabbit model of corneal epithelial defect.
Methods::
Human recombinant Lm5-PBS solution at a concentration of 100µg/ml was prepared. For defect model 1, a round epithelial defect of 10 mm in diameter was made using heptanol. Lm5 solution was applied 4 times a day until the wound was closed. The vehicle alone was applied to the contralateral eye as a control. The defect area was measured by image analyzing software to evaluate the healing process (n=5). For defect model 2, superficial keratectomy was performed using 9mm-diameter trephine, and the healing course was observed in a manner similar to that stated previously (n=6). In addition, the corneas were excised and examined by light microscopy and electron microscopy.
Results::
Epithelial defects of the Lm5 treated cornea and the control were closed until 96 and 108 hrs, respectively, in defect model 1, and until 192 and 204 hrs, respectively, in defect model 2, but no statistically significant difference was observed in healing rate. Histological examination did not reveal a notable difference in the morphology between the two experimental groups.
Conclusions::
In this study, the topical Lm5 solution did not exhibit a significant effect on corneal epithelial wound healing with a rabbit model. Further examination by a different protocol (the way of application, the concentration of solution, the animal model, etc.) is needed for a better understanding of the in vivo effect of Lm5 on corneal epithelial wound healing.
Keywords: cornea: epithelium • wound healing