Engineering Shape to Overcome Contraction: The Role of Polymer-Collagen Hybrids in Advanced Dermal Substitutes

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Science

Background:

• Collagen gels are standard dermal equivalents but suffer from rapid cell-mediated contraction, limiting functional tissue formation.
• Mechanical instability and rapid degradation of scaffolds hinder the development of robust dermal substitutes.
• Hybrid constructs (HCs) integrating collagen with degradable polymeric scaffolds are proposed to enhance mechanical stability and tissue integration.

Purpose of the Study:

• To screen various polycaprolactone (PCL) and poly D,L-lactide (PLA50) based scaffolds for creating stable HCs.
• To evaluate the processability, resistance to cell-mediated contraction, and degradation of different polymeric scaffolds.
• To identify optimal hybrid constructs for improved fibroblast behavior and potential in vivo applications.

Main Methods:

• Screening of homopolymers (PCL, PLA50), blends (PCL/PLA50), and copolymers (PCLLA50) for scaffold fabrication.
• Scaffold processing via electrospinning and 3D-printing, followed by integration with collagen gels to form HCs.
• Assessment of HCs' resistance to cell-mediated contraction, scaffold degradation, fibroblast distribution, and cell proliferation.

Main Results:

• Scaffolds with higher PCL content demonstrated better structural stability and ease of processing.
• HCs based on poly(D,L-lactide-co-caprolactone) 90/10 (PCLLA50 90/10) showed superior resistance to contraction (5%-17% area reduction).
• PCLLA50 90/10 HCs promoted better fibroblast distribution, myofibroblastic differentiation, and increased cell proliferation compared to collagen-only controls.

Conclusions:

• Hybrid constructs incorporating PCLLA50 90/10 scaffolds offer significant improvements in mechanical stability and cell response over traditional collagen gels.
• The electrospun PCLLA50 90/10 scaffold demonstrated notable advantages in cell proliferation and overall performance.
• These findings highlight PCLLA50 90/10-based HCs as promising candidates for future in vivo tissue engineering studies.