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Updated: Aug 6, 2026
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A Novel Stretching Platform for Applications in Cell and Tissue Mechanobiology
Published on: June 3, 2014
Moderately Reduced Contractility Decreases Epithelial Cell-Cell Contact Rupture Under Large External Stretch
S Sharmin1, C Obermeyer1, V Maruthamuthu1
1Department of Mechanical & Aerospace Engineering, Old Dominion University, Norfolk, VA.
Biorxiv : the Preprint Server for Biology
|July 17, 2026
Summary
Moderate inhibition of cell contractility preserves epithelial barrier integrity under mechanical stretch by reducing internal forces and increasing tissue compliance. This protects cell-cell contacts from ruptures during strain.
Area of Science:
- Biophysics
- Cell Biology
- Tissue Engineering
Background:
- Epithelial sheets require robust barrier function during mechanical stress.
- Actomyosin contractility stabilizes cell-cell junctions, but its interaction with external strain is unclear.
Purpose of the Study:
- Investigate the biophysical trade-offs between actomyosin contractility and epithelial barrier resilience under mechanical stretch.
- Determine how moderate contractility inhibition affects epithelial integrity during large deformations.
Main Methods:
- Used Madin-Darby Canine Kidney (MDCK) cell islands.
- Applied a custom-built biaxial stretching device for 38% linear stretch.
- Utilized non-muscle myosin II inhibitor (blebbistatin) at 10 μM.
- Performed traction force microscopy and nanoindentation.
Main Results:
- 10 μM blebbistatin maintained cell-cell contact integrity without stretch.
- Blebbistatin-treated islands showed fewer ruptures under 38% stretch compared to controls.
- Reduced cell-generated strain energy (>60%) and cellular Young's modulus (>40%) were observed.
Conclusions:
- Moderate contractility inhibition protects epithelial junctions by reducing active tensile and passive elastic forces during stretch.
- This shift towards a more compliant state preserves barrier integrity under severe mechanical challenge.
- Systemic force reduction is key, outweighing potential loss of adhesion strength.
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