AN INVESTIGATION OF PREFERENTIAL FIBROBLAST WOUND REPOPULATION USING A NOVEL IN-VITRO WOUND MODEL

TO OVERCOME THE DIFFICULTIES Of studying wounding and wound repopulati on in monolayer systems, a 3-dimensional model of wound repopulation h as been developed which allows the in vitro investigation of fibroblas t migration in response to experimental wounding. This model was utili zed to determine whether fibroblasts derived from sites which demonstr ate preferential healing (child and oral mucosal fibroblasts) possesse d an increased ability to repopulate experimental wounds when compared to adult dermal fibroblasts. Fibroblasts were established from specim ens derived from healthy donors undergoing minor elective surgery. Sta ndard wounds were created in fibroblast populated collagen lattices (F PCLs) which were then overlaid upon an extracellular wound matrix. Fib roblast repopulation of the wounds was studied over 12 days using ligh t-and scanning electron microscopy and quantified using computerized i mage analysis. Wound repopulation by fibroblasts derived from child do nors (n = 3) was significantly (P < 0.001) more rapid than their adult tissue-matched counterparts (n = 3). Wound repopulation by oral mucos al fibroblasts (n = 3) was significantly greater than that exhibited b y age-matched dermal fibroblasts (n = 3; P < 0.05). These differences were not reflected in differences in DNA synthesis (P > 0.5) or cell n umber (P > 0.5) within similar attached FPCL systems, These findings f urther support the concept of a gradual transition from the fetal to a dult phenotype in wound healing. The potential applications of the mod el are discussed.