Experimental model for local application of growth factors in skin re-epithelialisation

We did an experimental study to assess the effects of different growth fact ors on re-epithelialisation of skin wounds by creating a partial-thickness defect in rats with a handle dermatome. Three different growth factors that are particularly involved in the re-epithelialisation phase of wound repai r (epidermal growth factor (EGF), keratinocyte growth factor (KGF), and bas ic fibroblast growth factor (FGF-b) n = 10 in each group) were applied loca lly in a hydrocolloid dressing containing solutions of the different factor s (EGF 10 mu g/ml, KGF 3.3 ng/ml, bFGF 1 mu g/ml). The dressings were chang ed daily. The thickness of the epithelium, the percentage of re-epitheliali sation, and the maturity of the epithelium were quantified and measured mor phometrically. The results showed that: the experimental model allowed us t o apply the growth factors, while continuously maintaining the dose within the maximum activity of the growth factor; when EGF, KGF, and bFGF were giv en according to the protocol there was significant thickening of the new ep idermis (p < 0.01) and acceleration of the re-epithelialisation (p < 0.05) rate compared with controls, and significantly more mature epithelium grew (p < 0.05) all of which were evident on both the third and the fifth days; and EGF and KGF cause a more epidermal thickening than bFGF.