Contact enhancement of locomotion in spreading cell colonies

TL;DR

This study investigates how contact interactions influence cell colony spreading, revealing that such interactions enhance individual cell persistence and speed up early dispersal, suggesting a need for models to incorporate internal states.

Contribution

The paper uncovers a novel contact enhancement of locomotion in cell colonies and highlights the importance of internal states in modeling cell motility.

Findings

Contact interactions increase cell persistence during early spreading.

Cell proliferation and chemical interactions dominate at different times.

Active particle models should include internal states for accurate predictions.

Abstract

The dispersal of cells from an initially constrained location is a crucial aspect of many physiological phenomena ranging from morphogenesis to tumour spreading. In such processes, the way cell-cell interactions impact the motion of single cells, and in turn the collective dynamics, remains unclear. Here, the spreading of micro-patterned colonies of non-cohesive cells is fully characterized from the complete set of individual trajectories. It shows that contact interactions, chemically mediated interactions and cell proliferation each dominates the dispersal process on different time scales. From data analysis and simulation of an active particle model, we demonstrate that contact interactions act to speed up the early population spreading by promoting individual cells to a state of higher persistence, which constitutes an as-yet unreported contact enhancement of locomotion. Our findings suggest that the current modeling paradigm of memoryless interacting active particles may need to be extended to account for the possibility of internal states and history-dependent behaviour of motile cells.