High-Concentration Type I Atelocollagen Enhances Early Cartilage Regeneration: An In Vivo Comparative Study.

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Orthopedic Surgery

Background:

• Type I atelocollagen is utilized for treating full-thickness chondral lesions.
• Limited data exists on the concentration-dependent effects of atelocollagen scaffolds on chondrogenesis.

Purpose of the Study:

• To evaluate the in vitro and in vivo chondrogenic potentials of low-, intermediate-, and high-concentration atelocollagen-based scaffolds.
• To assess these scaffolds in a rabbit model of osteochondral defects.

Main Methods:

• Human mesenchymal stem cells (hMSCs) were encapsulated in 3%, 6%, and 9% type I collagen gels.
• Osteochondral defects were created in rabbits and treated with microfracture alone or with varying concentrations of atelocollagen.
• Outcomes were assessed macroscopically and histologically at 4, 8, and 12 weeks.

Main Results:

• High-concentration (9%) atelocollagen scaffolds showed significantly higher macroscopic scores at 8 weeks, indicating near-complete defect filling and smooth surface restoration.
• At 12 weeks, all atelocollagen concentrations significantly improved macroscopic and histological scores compared to microfracture alone.
• The 9% atelocollagen group achieved the highest overall histological scores, demonstrating superior cartilage regeneration.

Conclusions:

• High-concentration atelocollagen scaffolds significantly enhance cartilage regeneration efficiency and quality.
• These scaffolds provide mechanical support and a favorable microenvironment for chondrogenesis.
• Atelocollagen-based scaffolds represent a promising therapeutic strategy for osteochondral defects.