All-trans retinoic acid (RA) stimulates events in organ-cultured human skin that underlie repair. Adult skin from sun-protected and sun-exposed sites responds in an identical manner to RA while neonatal foreskin responds differently. - Varani,J.; Perone,P.; Griffiths,CE.; Inman,DR.; Fligiel,SE.; Voorhees,JJ. (J Clin Invest, 1994)