In vitro models to study wound healing fibroblasts

Phenotypic and contractile properties of human fibroblasts from dermis and from an experimental wound model were studied in vitro. When cultured in monolayer, dermal fibroblasts had an elongated spindle shape, were small in diameter and grew at a high rate. Wound fibroblasts grew slowly and were large, star shaped and had cytoplasmic stress fibres. Smooth muscle alpha actin was detected in 10 per cent of dermal cells, whereas 20–80 per cent of wound fibroblasts contained this protein in their cytoplasm. The contractile property of cells was evaluated using a three-dimensional cell culture model. Our results show that wound fibroblasts contract collagen gels during the first days more strongly than dermal fibroblasts. These results show that, in vitro, wound fibroblasts have greater contractile capacity than dermal cells. The significant proportion of wound fibroblasts containing α-smooth muscle actin suggests that α-smooth muscle actin ratio may be related to wound contraction.