During development and wound healing, tissues rapidly change in size, shape, composition, and in their mechanical characteristics. Cells within these tissues – which are of course responsible for making these tissues in the first place! – are exposed to a variety of forces, including tension, compression and shear, as well as the static mechanical properties of the stuff they grow on (other cells and ‘extracellular matrix’). It’s now widely appreciated that cells can feel and respond to these forces by moving, growing and differentiating.

We are interested in finding out how the mechanical characteristics of the growth environment direct cells how to behave, for example in the earliest stages of differentiation in the developing embryo, in cancer progression, and in processes involved in wound healing and tissue regeneration. We hope that our results might give us a better understanding of how to promote improved regeneration and healing following injury.

One application of this research is in the skin. Skin is made up of several layers, the most important of which are the epidermis (outer layer) and the dermis (inner layer). When skin is injured, often a large amount of this tissue is lost. During healing, the ‘wound bed’ begins to fill up with cells and proteins, which slowly replace the missing skin.

At the same time, new epidermis begins to grow and migrate out from the edges of the wound to form a new, outer, epidermal layer. Scientists know a great deal about the chemical mechanisms that control this, but we think that the mechanical properties – essentially how hard or soft the wound is – also affect how quickly and well this happens. We currently don’t know much about such effects.

To find out, we are investigating how the stiffness of materials affects how epidermal cells behave. We are growing skin cells on synthetic materials that vary in how hard or soft they are, and we are studying how these properties affect how cells grow, differentiate and migrate. Ultimately we hope to use the information we find out to better control wound healing in the clinic.