The simple model of cell prestress maintained by cell incompressibility

Living cells are reinforced by polymer fibers (the so-called cytoskeleton) which are responsible for their mechanical behaviour. There are many evidences that these fibres are prestressed without an external load. To include this prestress into mechanical models of living tissues is not an easy task. We propose an approach in which the intracellular prestress is maintained by the incompressibility of cells. A simple illustrative structure is studied in order to determine the dependence of stiffness on the level of prestress. Some macroscopic models of living tissues with prestressed cells are formulated. The results show a clear dependence of the macroscopic mechanical response on the level of prestress at microscale. The model exhibits some features of living cells (prestress-induced stiffening, strain hardening).