Re-epithelialization: advancing epithelium frontier during wound healing.

Area of Science:

• Biophysics
• Mathematical Biology
• Dermatology

Background:

• Skin integrity is crucial for protection; injury necessitates wound healing, a complex process involving tissue regeneration.
• Re-epithelialization, the migration of epithelial cells to cover wounds, is a critical phase of wound healing.

Purpose of the Study:

• To develop a theoretical model for the re-epithelialization phase of wound healing in a circular wound.
• To analyze the stability of the re-epithelialization process driven by chemotaxis.

Main Methods:

• A theoretical model incorporating chemoattractant diffusion, cell receptor uptake, epithelial cell migration, tension, and proliferation was developed.
• Darcy's law was used to model cell migration, transforming the biological problem into a free-boundary problem.
• The model was analyzed in a circular geometry to derive explicit solutions and perform stability analysis.

Main Results:

• The model provides explicit solutions for wound closure dynamics.
• Stability analysis revealed that re-epithelialization is an unstable process for realistic, centimeter-sized wounds.
• The model's predictions align with experimental observations, indicating that perfect circular wound closure is not typically achieved.

Conclusions:

• The theoretical model elucidates the complex dynamics of wound re-epithelialization.
• Chemotaxis-driven re-epithelialization is inherently unstable for clinically relevant wound sizes.
• The findings explain the deviation from perfect circular closure observed in experimental and clinical settings.