A comparison of newborn versus old skin fibroblasts, their potential for tissue repair

An assessment was made of the ability of human skin fibroblasts from newborn and old subjects to produce intracellular urokinase inhibitor and urokinase-plasminogen activator when exposed to phorbol myristate acetate. Urokinase inhibitor produced by human skin fibroblasts may be essential for cell growth regulation. The expression of urokinase inhibitor and/or urokinase-plasminogen activator may possibly be age-related. The principal observation that newborn skin fibroblasts show a low level and poorly sustained production of intracellular inhibitors of urokinase could help to explain the flexibility of the wound healing process in the foetus.