Accelerating Bone Healing by Decorating BMP-2 on Porous Composite Scaffolds

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Orthopedic Surgery

Background:

• Polymeric scaffolds are crucial for bone repair but often lack sufficient bioactivity.
• Enhancing scaffold bioactivity is key to improving bone regeneration outcomes.

Purpose of the Study:

• To develop osteoinductive poly(ε-caprolactone) (PCL) composite scaffolds with enhanced bioactivity for bone regeneration.
• To investigate the effect of nanohydroxyapatite (nHA), bioglass (BG), and polydopamine (pDA)-bound bone morphogenetic protein-2 (BMP-2) on scaffold properties and osteogenic potential.

Main Methods:

• Composite scaffolds were fabricated using PCL, nHA, BG, and pDA-BMP-2.
• Scaffold hydrophilicity, cell affinity, and BMP-2 release kinetics were evaluated.
• In vitro osteogenic differentiation of bone marrow stromal cells was assessed.
• In vivo studies were conducted using rabbit calvarial defect models.

Main Results:

• pDA deposition enhanced scaffold hydrophilicity and cell affinity.
• pDA facilitated sustained release of BMP-2.
• PHB-pDA-BMP-2 scaffolds significantly induced osteogenic differentiation of stromal cells compared to controls.
• Complete bone healing of calvarial defects was observed in rabbits treated with PHB-pDA-BMP-2 scaffolds within 12 weeks.

Conclusions:

• The developed PHB-pDA-BMP-2 composite scaffolds exhibit significant osteoinductive properties.
• These scaffolds demonstrate potent osteogenic capability, leading to complete bone regeneration in vivo.
• The designed scaffolds hold considerable promise for clinical applications in bone defect repair and regeneration.