Motile cells reshape extracellular biopolymer networks via force chain formations

Cells migrate within the extracellular matrix (ECM) by exerting local contractile forces. These forces remodel the ECM, forming force chain networks spanning multiple cell lengths. To investigate the interplay of multiple cellular forces with network architecture, including topology and disorder, we developed a simulation model of motile contractile cells on a diluted triangular lattice. Cells migrate in a tension-dependent, stochastic manner, with a higher probability of moving toward neighboring filaments when experiencing low local tension and a lower probability when under high local tension. With these simple moving rules, we observed cells form robust force chains, leading to an emergent high-tension network. Our results show that bulk stress and the fraction of high-tension filaments increase over time, stabilizing at a fluctuating plateau and indicating a non-equilibrium steady state. The pore size in the force chain network increases with higher cell density but decreases with network connectivity. Additionally, cell clustering is primarily driven by cell density, while network connectivity has a limited effect. Our findings provide insights into how cellular forces could reshape ECM networks, with broader implications for understanding tissue remodeling in processes like development and fibrosis.