Sustained Release of Bone Morphogenetic Protein 2/Chitosan-Collagen Scaffold Repairs Rabbit Knee Joint Cartilage...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Orthopedic Surgery

Background:

• Cartilage defects pose significant clinical challenges.
• Effective regeneration strategies are needed for articular cartilage repair.
• Biomimetic scaffolds can deliver therapeutic agents to promote tissue healing.

Purpose of the Study:

• To evaluate the efficacy of a collagen-binding domains-bone morphogenetic protein 2 (CBD-BMP-2) composite scaffold for cartilage defect repair.
• To assess the physicochemical properties and in vitro release kinetics of the CBD-BMP-2 scaffold.
• To investigate the in vivo cartilage regeneration potential of the CBD-BMP-2 scaffold in a rabbit model.

Main Methods:

• Preparation and characterization of a chitosan-collagen scaffold.
• Construction of a plasmid encoding CBD and BMP-2 for scaffold functionalization.
• In vitro assessment of BMP-2 controlled release.
• Establishment of a rabbit knee cartilage defect model with control, CBD, and CBD-BMP-2 treatment groups.
• Evaluation of cartilage repair using gross observation, MRI, histological staining, and immunohistochemistry (IHC).

Main Results:

• The CBD-BMP-2 composite scaffold exhibited favorable physicochemical properties, supporting cell attachment and proliferation.
• In vitro studies demonstrated sustained BMP-2 release from the scaffold for over 30 days.
• In vivo, the CBD-BMP-2 group showed significantly superior cartilage regeneration compared to control and CBD-only groups.
• Histological analysis revealed well-structured new cartilage with abundant matrix and increased type II collagen expression in the CBD-BMP-2 group.

Conclusions:

• The CBD-BMP-2 composite scaffold possesses excellent physicochemical properties and controlled-release capabilities.
• This scaffold effectively promotes cartilage regeneration and repair in a rabbit knee defect model.
• The CBD-BMP-2 scaffold represents a promising therapeutic approach for treating articular cartilage defects.