No abstract

Cell-based modelling frameworks such as cellular Potts are well-established tools to spatially model cell behavior and tissue morphogenesis. These models generally represent the extracellular matrix (ECM) with mean-field approaches, which assume substrate homogeneity. This assumption breaks down with fibrous ECM, which has non-trivial topology and mechanics. Here, we extend the cellular Potts software library Tissue Simulation Toolkit with the molecular mechanics framework hoomd-blue. We model cells mechanically interacting through discrete focal adhesion-like sites with an ECM fiber network modelled as bead-spring chains. Using a case study of an isolated contractile cell straining a randomly-oriented fiber network, we demonstrate agreement with experimental fiber densification and displacement dynamics. Further, we apply in silico atomic force microscopy to show local cell-induced network stiffening consistent with experiments. Our model overcomes the limitation of mean-field approaches to modelling ECM, and lays the foundation to investigate biomechanical cell-ECM interactions in a multicellular context.