Biomembrane-mimicking lipid bilayer system as a mechanically tunable cell substrate

Area of Science:

• Biomaterials Science
• Cell Biology
• Mechanobiology

Background:

• Cellular functions like adhesion and contraction are influenced by the extracellular matrix's elastic properties.
• The response of cells to complex viscoelastic and plastic material properties, common in vivo, remains largely unexplored.

Purpose of the Study:

• To investigate fibroblast responses to biomembrane-mimicking cell substrates with tunable viscoelastic and plastic properties.
• To determine whether cells sense matrix compliance or dissipative properties.

Main Methods:

• Utilized polymer-tethered bilayer substrates with adjustable compliance.
• Assessed cell morphology, motility, stiffness, contractile forces, and adhesive contact size.
• Compared responses on substrates with varying mechanical properties to soft polyacrylamide and hard glass.

Main Results:

• Fibroblast morphology, motility, stiffness, contractile forces, and adhesive contact size decreased on more compliant matrices.
• Cellular responses showed less sensitivity to changes in the matrix's dissipative properties.
• Cells predominantly responded to the effective matrix compliance, a combination of substrate and ligand mechanics.

Conclusions:

• Cells can sense and adapt to the effective compliance of their microenvironment.
• Matrix compliance, rather than dissipative properties, is the primary mechanical cue influencing cell behavior.