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Updated: Aug 8, 2026
09:47
A Microfluidic Technique to Probe Cell Deformability
Published on: September 3, 2014
Hydrodynamic narrowing of tubes extruded from cells
F Brochard-Wyart1, N Borghi, D Cuvelier
1Laboratoire Physicochimie Curie, Institut Curie/Centre National de la Recherche Scientifique, Unité Mixte de Recherche 168, 11, rue Pierre et Marie Curie, 75231 Paris Cedex 5, France. francoise.brochard-wyart@curie.fr
Summary
We found that the force needed to pull a lipid tube from a cell decreases with velocity, explained by Newtonian flow and decreasing tether diameter, not viscoelasticity.
Area of Science:
- Cellular mechanics
- Biophysics
- Cytoskeletal dynamics
Background:
- Extruding lipid tubes from cells involves membrane friction with the cytoskeleton.
- Neutrophil tethers show shear thinning, previously attributed to viscoelastic membrane flow.
Purpose of the Study:
- To propose an alternative explanation for the shear thinning response in lipid tube extrusion.
- To investigate the relationship between pulling force, extrusion velocity, and membrane properties.
Main Methods:
- Analysis of the pulling force (f) as a function of extrusion velocity (L).
- Modeling based on Newtonian fluid dynamics and membrane tension.
Main Results:
- The shear thinning response can be explained by Newtonian flow.
- Tether diameter decreases as membrane tension increases with velocity.
- Pulling force scales with velocity as L(1/3).
Conclusions:
- The observed 'shear thinning' is a result of decreasing tether diameter and increasing membrane tension.
- Newtonian flow provides a simpler explanation than viscoelasticity for this phenomenon.
- The L(1/3) force dependence aligns with experimental data across cell types.
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