The inter-follicular epidermis (IFE) forms the outer-most layer of the skin. Many individual components fundamental to healthy IFE structure are known: proliferation occurs only in a basal layer; above this layer cells differentiate into keratinocytes forming further distinct layers before they are shed from the surface. However, a definitive understanding of how the balance between proliferation, differentiation, and cell shedding is maintained in IFE tissue during homeostasis does not yet exist.
We have developed an agent-based multi-cellular computational model to simulate tissue homeostasis in the skin. Epidermal cells are represented as overlapping spheres, and cell divisions are represented as stochastic time-driven events. Cell movement is determined by adhesive attractive forces and repulsive forces between other cells and the basal membrane. The magnitude of these forces depends upon the types of the interacting bodies, and can vary depending on factors such as cell age and location.
Using this model we have analysed the impact of different cell mechanisms and behaviours on the tissue in order to investigate alternate hypotheses around maintenance of tissue structure. Results of this study provide insights into the critical mechanisms and behaviours, and will guide the future integration of detailed biochemical regulation processes.