Emergent intercellular junction stability during cyclic tissue loading

Area of Science:

• Biophysics
• Cell Biology
• Materials Science

Background:

• Epithelial tissues experience cyclic deformations physiologically.
• Intercellular adhesion complexes are crucial for tissue mechanical integrity and strength.
• Understanding adhesion complex response to dynamic loading is vital for tissue health.

Purpose of the Study:

• To investigate epithelial tissue resilience under cyclic loading.
• To model intercellular adhesion complex dynamics under varying tension.
• To establish a framework linking adhesion dynamics to tissue mechanics.

Main Methods:

• Quantitative experiments on Madin-Darby canine kidney (MDCK) cell monolayers.
• Computational modeling of intercellular adhesion complexes with force-dependent detachment rates.
• Analysis of tissue lifetime and deformation under static vs. cyclic loading.

Main Results:

• Cyclic loading significantly prolongs tissue lifetime and increases maximum deformation tolerance.
• Repair mechanisms during low-tension phases contribute to enhanced resilience.
• A model identified intrinsic rupture and repair timescales, defining three tissue behavior regimes.
• Universal stability maps were generated by normalizing loading parameters by material timescales.

Conclusions:

• Epithelial resilience under cyclic forces arises from stochastic adhesion bond dynamics.
• The study provides a predictive framework for tissue mechanics under physiological cyclic loading.
• Adhesion complex turnover is a key determinant of macroscopic tissue strength and stability.