Viscoelastic properties of suspended cells measured with shear flow deformation cytometry
- York University, Canada
- University of Erlangen-Nuremberg, Germany
- Aix-Marseille Université, CNRS, U1006 INSERM, France
- Max Planck Institute for the Science of Light, Germany
- University Hospital Erlangen, Germany
- University of Bayreuth, Germany
Abstract
Numerous cell functions are accompanied by phenotypic changes in viscoelastic properties, and measuring them can help elucidate higher-level cellular functions in health and disease. We present a high-throughput, simple and low-cost microfluidic method for quantitatively measuring the elastic (storage) and viscous (loss) modulus of individual cells. Cells are suspended in a high-viscosity fluid and are pumped with high pressure through a 5.8 cm long and 200 μm wide microfluidic channel. The fluid shear stress induces large, near ellipsoidal cell deformations. In addition, the flow profile in the channel causes the cells to rotate in a tank-treading manner. From the cell deformation and tank treading frequency, we extract the frequency-dependent viscoelastic cell properties based on a theoretical framework developed by R. Roscoe that describes the deformation of a viscoelastic sphere in a viscous fluid under steady laminar flow. We confirm the accuracy of the method using atomic force microscopy-calibrated polyacrylamide beads and cells. Our measurements demonstrate that suspended cells exhibit power-law, soft glassy rheological behavior that is cell cycle-dependent and mediated by the physical interplay between the actin filament and intermediate filament networks.
Data availability
The software is available on GitHub, the data are available on Dryad.
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Viscoelastic properties of suspended cells measured with shear flow deformation cytometryDryad Digital Repository, doi:10.5061/dryad.5hqbzkh8p.
Article and author information
Author details
Sebastian Johannes Müller
Funding
Deutsche Forschungsgemeinschaft (TRR-SFB 225 subprojects A01,A07 and B07)
- Elham Mirzahossein
European Union's Horizon 2020 (No 812772)
- Mar Eroles
European Union's Horizon 2020 (No 953121)
- Mar Eroles
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Gerum et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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