Connecting individual to collective cell migration.

Area of Science:

• Cell Biology
• Biophysics
• Developmental Biology

Background:

• Collective cell migration is crucial for development, regeneration, and disease, including cancer.
• Existing knowledge on molecular control of cell movement doesn't fully explain collective migration modes, especially for small cell groups.
• Understanding how individual cell behaviors integrate into collective motion is a key challenge.

Purpose of the Study:

• To derive a physical description of collective cell movements from first principles.
• To connect individual cell behaviors (adhesion, traction forces) to collective migration dynamics.
• To explain emergent collective behaviors in cell groups, even without biochemical signaling.

Main Methods:

• Developed a theoretical framework based on fundamental physical principles.
• Incorporated known cell behaviors like contact inhibition of locomotion and force-induced repolarization.
• Applied the model to groups of cells with arbitrary numbers.

Main Results:

• The theoretical description accurately models the motion of cell groups of any size.
• Successfully linked single-cell parameters to collective migration of small groups and expansion of large colonies.
• Explained how contact inhibition can lead to coherent collective behavior in groups without biochemical signals.
• Identified an optimal group size for maximal collective persistence.
• Demonstrated that cell proliferation prevents intercellular force buildup, facilitating colony expansion.

Conclusions:

• A unified physical framework can explain diverse collective cell migration phenomena.
• Individual cell properties directly influence collective behaviors and colony dynamics.
• Group size and cell proliferation are critical factors in collective cell migration and tissue formation.