Stem cell mechanical behaviour modelling: substrate's curvature influence during adhesion

Area of Science:

• Biophysics
• Cell Mechanics
• Computational Biology

Background:

• Cell behavior is influenced by the mechanical properties of their environment.
• The impact of substrate curvature on cellular mechanics is not well understood.
• Existing research lacks mechanistic explanations for cell-scale curvature effects.

Purpose of the Study:

• Investigate the mechanical state of adherent cells on curved substrates.
• Analyze intracellular component behavior under varying curvature.
• Elucidate mechanisms linking substrate curvature to cell mechanics.

Main Methods:

• Developed a numerical cell model using tensegrity structures theory.
• Employed non-smooth contact dynamics for simulations.
• Modeled intracellular components: cell membrane, cytoskeleton, nucleus, etc.
• Simulated cells on concave and convex hemispheres with varying radii.

Main Results:

• Substrate convexity influences cell shape and cytoskeletal force networks.
• Convex substrates lead to tensed stress fibers and cell membrane, compressed cytosol and microtubules, increasing cell stiffness.
• Concave substrates result in a more stable and rounded nucleus.
• Simulations revealed nucleus stability and mechanical responses to curvature changes.

Conclusions:

• Substrate curvature significantly alters intracellular mechanics and cell stiffness.
• Findings on nucleus stability may inform stem cell division and differentiation.
• Results offer insights into cell migration on curved surfaces.