Publikationen

The aim of this study was to determine whether the fetal alimentary tract shares the unique scarless healing properties of fetal skin. Full-thickness incisional gastric wounds were created and sutured closed in fetal lambs at 60, 75, and 120 days' gestation (full term, 145 days), and in adult control sheep. At the time of harvest, 14 days postwounding, dense fibrous adhesions were found intraperitoneally in all fetal and adult animals. Histologically, all fetal and adult gastric wounds healed with pronounced scar formation. In contrast to the adult wound, there was no significant inflammatory response in the fetal wounds. Because scar formed in the absence of inflammation in fetal gastric wounds, there is no obvious relation between scarring and the inflammatory response at this location. This study shows that not all fetal tissues exhibit scarless repair properties.

Journal: Journal of Pediatric Surgery (Volume 30, Issue 3, Pages 392-395)

Human fetal skin heals via scarless regeneration, whereas adult skin heals with scar. Scarless repair may reflect a distinct cytokine milieu. We studied the role of the cytokine transforming growth factor beta (TGFβ) using an established model of scarless human fetal skin repair in which human fetal skin is transplanted into a subcutaneous pocket on the flank of an adult nude mouse. In this model, wounded 16-week-gestation human fetal skin heals without scar, whereas wounded adult skin heals with scar. Seven days after transplantation, incisional wounds were made in the skin grafts. In the first phase of the study, wounds were harvested from 1 hour to 4 weeks postwounding, and immunohistochemistry was performed for TGFβ (isoform nonspecific), TGFβ1, and TGFβ2. Scarfree wounds in the fetal skin grafts did not show TGFβ staining. In contrast, wounds in adult grafts that heal with scar demonstrated isoform nonspecific TGFβ staining from 6 hours through 21 days, TGFβ1 from 6 hours through 21 days, and TGFβ2 from 12 hours through 7 days. In the second phase of the study, a slow-release disk with 0.01, 0.1, 1.0, or 10 μg of TGFβ1 was placed beneath the fetal skin graft at the time of wounding. Fourteen days postwounding, there was marked scarring in the fetal grafts treated with TGFβ1, and the size of the scar was proportional to the amount of TGFβ1 applied. The relative lack of TGFβ, a cytokine known to promote fibrosis, may be one reason why the fetus heals by regeneration rather than scarring. In contrast, the fibrosis characteristic of postnatal wound repair may be associated with an excess of TGFβ. These findings suggest that anti-TGFβ therapeutic strategies may ameliorate scar formation in children and adults.

Journal: Jourlan of Pediatric Surgery (Volume 30, Issue 2, Pages 198-203)