Viscoelasticity of multicellular surfaces.

Area of Science:

• Biophysics
• Cell Biology
• Materials Science

Background:

• Viscoelasticity in multicellular systems is modeled across short (sub-cellular), middle (cellular), and long (supra-cellular) time regimes.
• While short and middle time regimes are well-understood, long-time viscoelasticity, particularly collective cell migration, remains less defined.

Purpose of the Study:

• To investigate the poorly understood long-time regime of multicellular surface viscoelasticity.
• To explore the impact of collective cell migration on energy storage and dissipation in cell surfaces.
• To identify key parameters influencing constitutive models for long-time viscoelasticity.

Main Methods:

• Review and analysis of existing modeling approaches for multicellular viscoelasticity.
• Identification of key factors in collective cell migration affecting viscoelastic properties.
• Discussion of parameters such as cell volume fraction, distribution, and group shape.

Main Results:

• Collective cell migration introduces uncorrelated motility, impacting energy storage and dissipation.
• Migrating cell volume fraction, distribution, and group shape influence mechanical coupling between cell subpopulations.
• Existing constitutive models for long-time viscoelasticity require further experimental validation.

Conclusions:

• Long-time viscoelasticity is significantly influenced by collective cell migration dynamics.
• Mechanical coupling between migrating and resting cells is critical for accurate constitutive modeling.
• Experimental validation is essential for proposed models of long-time viscoelastic behavior, including stress relaxation and moduli.