Long Range Force Transmission in Fibrous Matrices Enabled by Tension-Driven Alignment of Fibers

TL;DR

This study investigates how tension-driven collagen fiber alignment enhances long-range force transmission in fibrous matrices, revealing key factors like fiber stiffness, cell shape, and polarization that influence cellular communication over distances.

Contribution

The paper introduces a constitutive law for collagen fiber reorientation and systematically analyzes the impact of fiber alignment on force transmission using simulations and analytical methods.

Findings

Fiber alignment enables long-range force transmission.

Cell shape and polarization significantly affect force range.

Tension-driven fiber alignment is crucial for cellular communication.

Abstract

Cells can sense and respond to mechanical signals over relatively long distances across fibrous extracellular matrices. Here, we explore all of the key factors that influence long range force transmission in cell-populated collagen matrices: alignment of collagen fibers, responses to applied force, strain stiffening properties of the aligned fibers, aspect ratios of the cells, and the polarization of cellular contraction. A constitutive law accounting for mechanically-driven collagen fiber reorientation is proposed. We systematically investigate the range of collagen fiber alignment using both finite element simulations and analytical calculations. Our results show that tension-driven collagen fiber alignment plays a crucial role in force transmission. Small critical stretch for fiber alignment, large fiber stiffness and fiber strain hardening behavior enable long-range interaction. Furthermore, the range of collagen fiber alignment for elliptical cells with polarized contraction is much larger than that for spherical cells with diagonal contraction. A phase diagram showing the range of force transmission as a function of cell shape and polarization and matrix properties is presented. Our results are in good agreement with recent experiments, and highlight the factors that influence long-range force transmission, in particular tension-driven alignment of fibers. Our work has important relevance to biological processes including development, cancer metastasis and wound healing, suggesting conditions whereby cells communicate over long distances.