Mathematical models of wound healing in embryonic and adult epidermis.

Epidermal wound healing occurs by quite different mechanisms in embryos and adults. In the latter case, it has long been known that cells crawl inwards via lamellipodia to close the defect. In the embryonic system, recent evidence suggests that healing may be caused by a quite different mechanism, namely the contraction of a cable of filamentous actin at the wound edge. The authors use mathematical modelling to investigate both systems. A mechanical model for the initial formation of the actin cable in embryonic epidermal wounds is presented, which incorporates the important phenomenon of stress-induced microfilament alignment. Also discussed is a reaction-diffusion model for the healing of adult wounds subject to autoregulation of cell division. In both cases, the results suggest possible biological mechanisms for key aspects of the healing process.