Relating cell shape and mechanical stress in a spatially disordered epithelium using a vertex-based model

Area of Science:

• Biophysics
• Developmental Biology
• Cell Biology

Background:

• Epithelial tissues exhibit complex cell shapes and mechanical properties crucial for development and function.
• Understanding the interplay between cell shape, mechanical stress, and tissue-level organization is fundamental in developmental biology.

Purpose of the Study:

• To investigate the relationship between cell shape and mechanical stress in planar epithelial monolayers.
• To develop and validate a vertex-based model for predicting tissue-level mechanical behavior and cell shape correlations.

Main Methods:

• Utilized a popular vertex-based computational model for simulating spatially disordered planar epithelial monolayers.
• Derived stress tensor expressions from an energetic formulation to analyze cell and tissue-level mechanics.
• Fit model parameters to experimental data from Xenopus embryonic tissues.

Main Results:

• Demonstrated that principal axes of stress align with principal axes of cell shape in individual cells.
• Determined bulk effective tissue pressure for isotropic monolayers.
• Model predictions showed mechanical interactions generate mesoscopic patterns with long-range cell shape correlations.
• Identified potential correlations between mechanical/geometric cues and cell division orientation.

Conclusions:

• Mechanical interactions within epithelial monolayers significantly influence cell shape and tissue organization.
• The developed model provides insights into how physical forces shape developmental processes like cell division.
• Acknowledged limitations in capturing specific geometric features of Xenopus epithelial cells.