An adult-fetal skin interface heals without scar formation in sheep

Abstract

Background: Fetal skin heals by regeneration rather than by adult-type scarring. Prior studies indicate that scarless healing is an intrinsic property of fetal tissue.

Methods: To answer the question of whether fetal tissue could influence the healing of adjacent adult tissue, adult sheepskin was transplanted on the backs of 60-days' gestation fetal lambs (term, 145 days). At time points 1, 3, 7, 14, 21, 28, 42, 56, and 63 days after transplantation, the grafts were harvested and the interfaces between adult and fetal skin were analyzed.

Results: The adult-fetal interface healed without scar formation. Control fetal sheep autograft (fetal-fetal) interfaces healed without scar, and adult sheep autograft (adult-adult) interfaces healed with scar.

Conclusions: These results suggest that the juxtaposed fetal tissue prevented scar formation at the adult-fetal interface. We hypothesize that fetal cellular and matrix factors permit adjacent wounded adult tissue to heal without scar. These factors, once characterized, might be used clinically to induce scarless healing in children and adults.