Mean-field interactions between living cells in linear and nonlinear elastic matrices

Area of Science:

• Biophysics
• Cell Mechanics
• Theoretical Biology

Background:

• Living cells dynamically interact with their extracellular matrix (ECM).
• Cellular contractile forces are transmitted through the ECM, influencing neighboring cells.
• Understanding cell-cell mechanical communication is crucial for tissue development and disease.

Purpose of the Study:

• To investigate how mechanical interactions between contractile cells are mediated by the surrounding matrix.
• To analyze the influence of different cellular regulatory behaviors (displacement vs. stress) on cell-cell interactions.
• To explore the impact of matrix nonlinearity on these mechanical interactions.

Main Methods:

• Development of theoretical models for cell-matrix interactions.
• Calculation of mechanical work performed by cells deforming the matrix.
• Analysis of interaction energies based on cell arrangement and regulatory behavior.
• Inclusion of nonlinear matrix properties (strain-stiffening).

Main Results:

• Cells regulating displacement attract each other, independent of rigidity.
• Cells regulating active stress repel each other, with repulsion dependent on elastic moduli (bulk and shear).
• In nonlinear matrices, displacement regulation limits cell contraction, while stress regulation shows reduced interaction energy at high stress.

Conclusions:

• Cell-matrix mechanical interactions are significantly shaped by how cells regulate their forces.
• The mechanical properties of the extracellular matrix, including nonlinearity, play a key role in modulating cell-cell communication.
• This work offers theoretical insights into collective cell behavior driven by mechanical feedback loops.