Galectin-7 as a potential mediator of corneal epithelial cell migration.
OBJECTIVE
To assess the role of a carbohydrate-binding protein, galectin-7, in reepithelialization of corneal wounds.


METHODS
Transepithelial excimer laser ablations were performed on mouse corneas, and the wounds were allowed to partially heal in vivo for 18 to 22 hours. At the end of the healing period, expression levels of galectin-7 messenger RNA and protein were analyzed using semiquantitative reverse transcriptase-polymerase chain reaction, Western blot analysis, and immunohistochemical localization studies. To determine the effect of exogenous galectin-7 on reepithelialization of corneal wounds, corneas with 2-mm alkali burn wounds were allowed to partially heal in vitro for 20 to 24 hours in serum-free media in the presence or absence of recombinant galectin-7. At the end of the healing period, the wound areas were photographed and quantified.


RESULTS
Expression of galectin-7 messenger RNA and protein was markedly up-regulated in the corneal epithelium after injury. Exogenous galectin-7 stimulated reepithelialization of corneal wounds. The stimulatory effect of galectin-7 on corneal epithelial wound closure was specifically inhibited by a competing sugar, beta-lactose, but not by an irrelevant disaccharide, sucrose.


CONCLUSIONS
Galectin-7 has the potential to mediate corneal epithelial cell migration and reepithelialization of wounds.


CONCLUSIONS
These findings have broad implications for developing novel, galectin-based, therapeutic strategies for treatment of nonhealing corneal epithelial defects.
Cao
Zhiyi
Z
New England Eye Center, Center for Vision Research and Department of Ophthalmology, Tufts University School of Medicine, Boston, MA 02111, USA.
Said
Neveen
N
Wu
Helen K
HK
Kuwabara
Ichiro
I
Liu
Fu-Tong
FT
Panjwani
Noorjahan
N
D000818:Animals; D015153:Blotting, Western; D002057:Burns, Chemical / Q000188:drug therapy / Q000378:metabolism; D002465:Cell Movement / Q000502:physiology*; D003315:Cornea / Q000166:cytology* / Q000601:surgery; D004847:Epithelial Cells / Q000502:physiology*; D005126:Eye Burns / Q000139:chemically induced; D037161:Galectins / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D007124:Immunoenzyme Techniques; D054018:Lasers, Excimer; D051379:Mice; D008810:Mice, Inbred C57BL; D018903:Photorefractive Keratectomy; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012972:Sodium Hydroxide / Q000633:toxicity; D015854:Up-Regulation; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology
D037161:Galectins; C490487:Lgals7 protein, mouse; D012333:RNA, Messenger; D012972:Sodium Hydroxide