3D-Printed PCL/ACM Composite Scaffolds via Low-Temperature Deposition Manufacturing for Cartilage Regeneration

Background: Tissue-engineered cartilage offers a promising alternative for reconstructive surgery, yet composite scaffolds combining synthetic polymers with natural biomaterials face challenges in maintaining bioactivity while achieving adequate mechanical properties.

Methods: We fabricated composite scaffolds comprising polycaprolactone (PCL) and acellular cartilage matrix (ACM) using low-temperature deposition manufacturing (LDM) at −30°C. This approach enables uniform ACM integration while preserving its bioactive components. Scaffold morphology, mechanical properties, in vitro chondrocyte compatibility, and in vivo cartilage regeneration were systematically evaluated.

Results: The PCL/ACM scaffolds exhibited multi-scale porosity (macropores ~585 μm, micropores ~2.5 μm) with Young's modulus of 462 ± 119 kPa and compressive yield stress of 592 ± 87 kPa. After 2 weeks of in vitro culture, cell viability reached 92.36% ± 13.41%, with type II collagen expression showing a 1.85-fold increase compared to PCL-only controls (*p* < 0.001). In vivo implantation in nude mice demonstrated significantly enhanced glycosaminoglycan and type II collagen deposition at 16 weeks.

Conclusion: LDM effectively preserves ACM bioactivity while achieving homogeneous material distribution and satisfactory mechanical properties. The PCL/ACM composite scaffold represents a promising strategy for clinical tissue-engineered cartilage reconstruction.

Department of Rhinoplasty and Nasal Reconstruction, Chinese Academy of Medical Sciences & Peking Union Medical College, Plastic Surgery Hospital and Institute.

中国医学科学院整形外科医院 鼻整形再造中心