Phase field modelling of the mechanics of nucleated cells in confined spaces*

Biological cells strongly respond to the geometry and mechanics of their environment. Dynamic processes like development or cancer metastasis are strongly shaped by such mechanosensitive responses. In recent years, it has become clear that the cell nucleus is especially important in this context. Its large size and up-to 10-fold higher stiffness compared to the surrounding cytoplasm make it a mechanically distinct structure within an eukaryotic cell. However, many models for whole cell mechanics neglect the nucleus. Here, we present an extension of our elastic phase field method [1] to also include the nucleus. We introduce an additional compartment for the nucleus that represents its special elastic properties. We demonstrate the mechanical effect of the nucleus in two particularly interesting experimental situations namely the compression of cells between two plates and cell migration through a narrow channel.

[1] R. Chojowski, U.S. Schwarz, F. Ziebert, Reversible elastic phase field approach and application to biological cells, Eur. Phys. J. E 43, 63 (2020)