Microscopic collisions govern macroscopic aerotactic spreading through emergent transport coefficients
- 1University Lyon 1 CNRS
Abstract
Collective migration is often attributed to complex cell-cell communication, yet coordinated multicellular dynamics can also emerge in organisms lacking social interactions. Continuum descriptions successfully capture such behaviors but generally rely on phenomenological transport coefficients whose microscopic origin remains elusive. Here we show that these coefficients emerge from cell-cell collisions and can be independently determined from experiments. We investigate the aerotactic dispersal of confined colonies of the solitary amoeba Acanthamoeba castellanii, in which oxygen consumption continuously reshapes the local environment to generate self-organized guidance cues. Combining quantitative videomicroscopy, oxygen mapping with phosphorescent sensing films, and oxygen-controlled microfluidics, we directly measure both the oxygen landscape and the aerotactic response governing colony expansion. We then develop a Patlak-Keller-Segel (PKS) -type drift-diffusion model whose transport coefficients are entirely determined from independent experiments and microscopic-to-macroscopic modeling approach, without adjustable parameters. The model quantitatively reproduces the observed dynamics, including the coexistence of a fast ballistic front and a trailing transient accumulation band. We show that both diffusion and aerotactic transport are modulated by the same collision-controlled mechanism through density-dependent changes in cell persistence. More generally, our results establish transport coefficients as measurable emergent properties bridging microscopic cell dynamics and macroscopic collective behavior, providing a predictive framework for oxygen-guided migration in living active matter.
Related
- Flagellar number governs bacterial spreading and transport efficiency.
- H3K27me3 spreading organizes canonical PRC1 chromatin architecture to regulate developmental programs
- Measurement and Prediction of Unmixing‐Dependent Spreading due to Collinearity in Spectral Flow Cytometry
- Macroscopic Vibronic Coherence and Non-Dispersive Soliton Propagation Across a Protein-Solvent Interface
- ReLink: Reliable Deep Learning for Microscopic Motion Tracking.
BibTeX
@misc{ghazi2026microscopic,
title = {{Microscopic collisions govern macroscopic aerotactic spreading through emergent transport coefficients}},
author = {N. Ghazi and S. Hirose and K. Funamoto and V. Calvez and C. Anjard and O. Cochet-Escartin and M. Demircigil and J.-P. RIEU},
howpublished = {bioRxiv},
year = {2026},
month = oct,
doi = {10.64898/2026.10.08.757612},
url = {https://www.biorxiv.org/content/10.64898/2026.10.08.757612v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - Microscopic collisions govern macroscopic aerotactic spreading through emergent transport coefficients
AU - N. Ghazi
AU - S. Hirose
AU - K. Funamoto
AU - V. Calvez
AU - C. Anjard
AU - O. Cochet-Escartin
AU - M. Demircigil
AU - J.-P. RIEU
PY - 2026
DA - 2026/10/08
PB - bioRxiv
DO - 10.64898/2026.10.08.757612
UR - https://www.biorxiv.org/content/10.64898/2026.10.08.757612v1
AB - Collective migration is often attributed to complex cell-cell communication, yet coordinated multicellular dynamics can also emerge in organisms lacking social interactions. Continuum descriptions successfully capture such behaviors but generally rely on phenomenological transport coefficients whose microscopic origin remains elusive. Here we show that these coefficients emerge from cell-cell collisions and can be independently determined from experiments. We investigate the aerotactic dispersal of confined colonies of the solitary amoeba Acanthamoeba castellanii, in which oxygen consumption continuously reshapes the local environment to generate self-organized guidance cues. Combining quantitative videomicroscopy, oxygen mapping with phosphorescent sensing films, and oxygen-controlled microfluidics, we directly measure both the oxygen landscape and the aerotactic response governing colony expansion. We then develop a Patlak-Keller-Segel (PKS) -type drift-diffusion model whose transport coefficients are entirely determined from independent experiments and microscopic-to-macroscopic modeling approach, without adjustable parameters. The model quantitatively reproduces the observed dynamics, including the coexistence of a fast ballistic front and a trailing transient accumulation band. We show that both diffusion and aerotactic transport are modulated by the same collision-controlled mechanism through density-dependent changes in cell persistence. More generally, our results establish transport coefficients as measurable emergent properties bridging microscopic cell dynamics and macroscopic collective behavior, providing a predictive framework for oxygen-guided migration in living active matter.
ER -