Collagen Fibrils Mechanically Contribute to Tissue Contraction in an In Vitro Wound Healing Scenario

Area of Science:

• Biomedical Engineering
• Cell Biology
• Tissue Mechanics

Background:

• Wound contraction is a vital vertebrate survival mechanism driven by tensile forces for wound closure.
• Current understanding attributes tissue tension primarily to cellular forces from (myo-)fibroblasts.
• Pathological deviations in healing necessitate exploring additional modulatory factors beyond cellular contributions.

Purpose of the Study:

• To investigate the contribution of the extracellular matrix to macroscopic tissue tension during wound healing.
• To identify previously neglected factors influencing tissue tension and wound contraction.
• To understand the mechanical role of collagen fibrils in the wound healing process.

Main Methods:

• Utilized a biomaterial-based in vitro wound healing model.
• Employed in situ monitoring of tissue forces.
• Applied second harmonic imaging to visualize collagen fibril organization.

Main Results:

• Demonstrated that the extracellular matrix stores significant tensile forces, contributing to macroscopic tissue tension.
• Observed a correlation between the appearance of collagen fibrils and tissue contraction.
• Identified a mechanical contribution of tensioned collagen fibrils to the wound contraction process.

Conclusions:

• The extracellular matrix, specifically collagen fibrils, plays a critical, previously underestimated role in wound contraction.
• Understanding these matrix-mediated forces is crucial for advancing the comprehension of successful tissue healing.
• Findings offer insights into the underlying principles of misregulation in scar formation and tissue contractures.