Fetal wound healing using a genetically modified murine model: the contribution of P-selectin.
OBJECTIVE
During early gestation, fetal wounds heal with paucity of inflammation and absent scar formation. P-selectin is an adhesion molecule that is important for leukocyte recruitment to injury sites. We used a murine fetal wound healing model to study the specific contribution of P-selectin to scarless wound repair.


METHODS
Linear excisional wounds were created on the dorsa of E15.5 and E17.5 gestation fetuses in wild-type and P-selectin (-/-) mice (term = 19 days). Wounds were harvested at various time-points after wounding and analyzed using histology and immunohistochemistry.


RESULTS
The E15.5 wounds in both wild-type and P-selectin (-/-) fetuses healed scarlessly and with minimal inflammation, whereas E17.5 wounds healed with fibrosis and inflammation. However, the scars of the P-selectin (-/-) wounds appeared slightly different than wild-type. There were significantly more inflammatory cells in E17.5 wild-type wounds 6 hours after injury (P < .001), but the difference was no longer significant by 24 hours. Finally, reepithelialization was slower in the E15.5 knockout wounds compared to their wild-type counterparts.


CONCLUSIONS
Absence of P-selectin delays inflammatory cell recruitment and reepithelialization of fetal wounds; however, scar formation still occurs in late gestation wounds. The contribution of specific molecules to fetal wound healing can be elucidated using murine knockout or transgenic models.
Naik-Mathuria
Bindi
B
Division of Pediatric Surgery, Michael E. DeBakey Department of Surgery, Section of Leukocyte Biology, Baylor College of Medicine, Houston, TX 77030-2399, USA.
Gay
Andre N
AN
Yu
Ling
L
Hsu
Jean E
JE
Smith
C Wayne
CW
Olutoye
Oluyinka O
OO
D000818:Animals; D030801:Animals, Genetically Modified; D002921:Cicatrix / Q000196:embryology / Q000378:metabolism; D005355:Fibrosis / Q000196:embryology / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D007249:Inflammation / Q000196:embryology / Q000378:metabolism / Q000473:pathology; D015603:Keratinocytes / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D023421:Models, Animal; D019007:P-Selectin / Q000378:metabolism*; D014945:Wound Healing / Q000502:physiology*; D014947:Wounds and Injuries / Q000196:embryology* / Q000378:metabolism* / Q000473:pathology
D019007:P-Selectin