Adhesion as a trigger of droplet polarization in flowing emulsions

TL;DR

This study investigates how cell-cell adhesion influences droplet deformation and polarization in flowing emulsions, providing insights into tissue morphogenesis through biomimetic experiments.

Contribution

It demonstrates that adhesion affects droplet deformation and contact rupture, revealing a potential mechanism for polarization during morphogenesis.

Findings

Adhesive droplets are more deformed along the elongation axis.

Avalanche size distributions are similar for adhesive and repulsive droplets.

Adhesion impairs droplet contact rupture, affecting deformation.

Abstract

Tissues are subjected to large external forces and undergo global deformations during morphogenesis. We use synthetic analogues of tissues to study the impact of cell-cell adhesion on the response of cohesive cellular assemblies under such stresses. In particular, we use biomimetic emulsions in which the droplets are functionalized in order to exhibit specific droplet-droplet adhesion. We flow these emulsions in microfluidic constrictions and study their response to this forced deformation via confocal microscopy. We find that the distributions of avalanche sizes are conserved between repulsive and adhesive droplets. However, adhesion locally impairs the rupture of droplet-droplet contacts, which in turn pulls on the rearranging droplets. As a result, adhesive droplets are a lot more deformed along the axis of elongation in the constriction. This finding could shed light on the origin of polarization processes during morphogenesis.