Extracellular Matrix Alignment Directs Provisional Matrix Assembly and Three Dimensional Fibrous Tissue Closure

Area of Science:

• Biomedical Engineering
• Cell Biology
• Tissue Engineering

Background:

• Wound healing involves gap closure and provisional matrix deposition.
• Wound shape influences healing efficiency, but the role of extracellular matrix (ECM) alignment is unclear.

Purpose of the Study:

• Investigate the impact of wound curvature and ECM alignment on gap closure in a 3D fibrous tissue model.
• Determine how ECM structure affects fibroblast-mediated provisional matrix assembly.

Main Methods:

• Utilized microfabricated flexible micropillars to create 3D fibroblast-populated collagen microtissues with varying ECM alignments.
• Introduced wounds of different shapes and curvatures to these microtissues.
• Quantified provisional fibronectin matrix assembly rates in relation to local wound curvature and ECM alignment.

Main Results:

• Local wound curvature did not affect the rate of provisional matrix production.
• Provisional matrix assembly was slowest in regions of high ECM alignment and fastest in regions of low alignment.
• ECM structure influences wound shape and the ability of fibroblasts to deposit provisional matrix.

Conclusions:

• ECM alignment, rather than wound curvature, is a key factor in regulating provisional matrix assembly during wound healing.
• Findings reveal a significant interplay between ECM alignment, wound shape, and tissue repair.
• This research offers insights for improving tissue engineering strategies and understanding in vivo wound healing.