In contrast to adult wound healing with scar formation, which of the following are characteristic of scarless fetal skin repair?

E. Minimal angiogenesis.

DISCUSSION: The ability of a fetus to heal without scar formation depends on its gestational age at the time of injury and the size of the wound defect. In general, linear incisions heal without scar until late in gestation, whereas excisional wounds heal with scar at an earlier gestational age. The profiles of fetal proteoglycans, collagens, and growth factors are different from those in adult wounds. The less differentiated state of fetal skin is probably an important characteristic responsible for scarless repair. There is minimal inflammation and angiogenesis in fetal wounds. Fetal wounds are characterized by high levels of hyaluronic acid and its stimulator(s) with more rapid, highly organized collagen deposition. The roles of peptide growth factors such as TGF-b and basic fibroblast growth factor are less prominent in fetal than in adult wound healing. An understanding of scarless tissue repair has possible clinical applications in the modulation of adult fibrotic diseases and abnormal scar-forming conditions.