PHBV wet-spun scaffold coated with ELR-REDV improves vascularization for bone tissue engineering

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Large-scale bone tissue replacement requires 3D scaffolds, but limited nutrient and oxygen transport hinders cell survival.
• Vascularization is crucial for scaffold survival but cannot be immediately established post-implantation.
• Developing strategies for early vascularization is essential for the success of bone tissue engineering.

Purpose of the Study:

• To develop a 3D wet-spun bone tissue engineering scaffold promoting early vascularization.
• To functionalize poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds with an elastin-like recombinamer (ELR) peptide containing a REDV sequence.
• To evaluate the effect of ELR-REDV coating on scaffold properties and endothelial cell attraction.

Main Methods:

• Fabrication of 3D PHBV scaffolds using wet-spinning.
• Surface modification of PHBV scaffolds via oxygen plasma treatment and subsequent ELR-REDV peptide immobilization (PHBV-O2-ELR-REDV).
• Characterization of surface properties (wettability, topography, composition) and in vitro assessment of cell adhesion, proliferation, and migration using mesenchymal stem cells and human umbilical vein endothelial cells (HUVECs).

Main Results:

• Oxygen plasma treatment and ELR-REDV coating altered scaffold wettability, topography, and surface composition, creating a moderately hydrophilic surface.
• FTIR-ATR confirmed successful ELR-REDV immobilization on the PHBV scaffolds.
• While ELR modification did not significantly impact bone marrow mesenchymal cell adhesion or proliferation, it markedly increased HUVEC adhesion and migration (approx. 2.5-fold higher than untreated scaffolds after 14 days).

Conclusions:

• The developed PHBV-O2-ELR-REDV scaffolds demonstrate significant potential for inducing early vascularization in bone tissue engineering.
• The REDV sequence on the ELR peptide effectively promotes endothelial cell recruitment, a critical factor for nutrient supply in 3D implants.
• These findings suggest a promising approach to overcome vascularization limitations in large-scale bone regeneration applications.