Dataset Information

On-Chip Quantitative Measurement of Mechanical Stresses During Cell Migration with Emulsion Droplets.

ABSTRACT: The ability of immune cells to migrate within narrow and crowded spaces is a critical feature involved in various physiological processes from immune response to metastasis. Several in-vitro techniques have been developed so far to study the behaviour of migrating cells, the most recent being based on the fabrication of microchannels within which cells move. To address the question of the mechanical stress a cell is able to produce during the encounter of an obstacle while migrating, we developed a hybrid microchip made of parallel PDMS channels in which oil droplets are sparsely distributed and serve as deformable obstacles. We thus show that cells strongly deform droplets while passing them. Then, we show that the microdevice can be used to study the influence of drugs on migration at the population level. Finally, we describe a quantitative analysis method of the droplet deformation that allows measuring in real-time the mechanical stress exerted by a single cell. The method presented herein thus constitutes a powerful analytical tool for cell migration studies under confinement.

SUBMITTER: Molino D

PROVIDER: S-EPMC4931467 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

On-Chip Quantitative Measurement of Mechanical Stresses During Cell Migration with Emulsion Droplets.

Molino D D Quignard S S Gruget C C Pincet F F Chen Y Y Piel M M Fattaccioli J J

Scientific reports 20160704

The ability of immune cells to migrate within narrow and crowded spaces is a critical feature involved in various physiological processes from immune response to metastasis. Several in-vitro techniques have been developed so far to study the behaviour of migrating cells, the most recent being based on the fabrication of microchannels within which cells move. To address the question of the mechanical stress a cell is able to produce during the encounter of an obstacle while migrating, we develope ...[more]

PMID: 27373558

Similar Datasets

Project description:It is now evident that the cell nucleus undergoes dramatic shape changes during important cellular processes such as cell transmigration through extracellular matrix and endothelium. Recent experimental data suggest that during cell transmigration the deformability of the nucleus could be a limiting factor, and the morphological and structural alterations that the nucleus encounters can perturb genomic organization that in turn influences cellular behavior. Despite its importance, a biophysical model that connects the experimentally observed nuclear morphological changes to the underlying biophysical factors during transmigration through small constrictions is still lacking. Here, we developed a universal chemomechanical model that describes nuclear strains and shapes and predicts thresholds for the rupture of the nuclear envelope and for nuclear plastic deformation during transmigration through small constrictions. The model includes actin contraction and cytosolic back pressure that squeeze the nucleus through constrictions and overcome the mechanical resistance from deformation of the nucleus and the constrictions. The nucleus is treated as an elastic shell encompassing a poroelastic material representing the nuclear envelope and inner nucleoplasm, respectively. Tuning the chemomechanical parameters of different components such as cell contractility and nuclear and matrix stiffnesses, our model predicts the lower bounds of constriction size for successful transmigration. Furthermore, treating the chromatin as a plastic material, our model faithfully reproduced the experimentally observed irreversible nuclear deformations after transmigration in lamin-A/C-deficient cells, whereas the wild-type cells show much less plastic deformation. Along with making testable predictions, which are in accord with our experiments and existing literature, our work provides a realistic framework to assess the biophysical modulators of nuclear deformation during cell transmigration.

Project description:Cell migration involves the dynamic formation and release of cell-substrate adhesions, where the exertion and detection of mechanical forces take place. Members of the calpain family of calcium-dependent proteases are believed to have a central role in these processes, possibly through the regulation of focal adhesion dynamics. The ubiquitous calpains, calpain 1 (mu-calpain) and calpain 2 (m-calpain), are heterodimers consisting of large catalytic subunits encoded by the Capn1 and Capn2 genes, respectively, and the small regulatory subunit encoded by Capn4. We have examined the role of the calpain regulatory small subunit in traction force production and mechanosensing during cell migration. Capn4-deficient or rescued cells were plated on flexible polyacrylamide substrates, for both the detection of traction forces and the application of mechanical stimuli. The total force output of Capn4-deficient cells was approximately 75% lower than that of rescued cells and the forces were more randomly distributed and less dynamic in Capn4-deficient cells than in rescued cells. Furthermore, Capn4-deficient cells were less adhesive than wild-type cells and they also failed to respond to mechanical stimulations by pushing or pulling the flexible substrate, or by engaging dorsal receptors to the extracellular matrix. Surprisingly, fibroblasts deficient in calpain 1 or calpain 2 upon siRNA-mediated knockdown of Capn1 or Capn2, respectively, did not show the same defects in force production or adhesion, although they also failed to respond to mechanical stimulation. Interestingly, stress fibers were aberrant and also contained fewer colocalised vinculin-containing adhesions in Capn4-deficient cells than Capn1- and Capn2-knockdown cells. Together, these results suggest that the calpain small subunit plays an important role in the production of mechanical forces and in mediating mechanosensing during fibroblast migration. Furthermore, the Capn4 gene product might perform functions secondary to, or independent of, its role as a regulatory subunit for calpain 1 and calpain 2.

Dataset Information

On-Chip Quantitative Measurement of Mechanical Stresses During Cell Migration with Emulsion Droplets.

Publications

On-Chip Quantitative Measurement of Mechanical Stresses During Cell Migration with Emulsion Droplets.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets