3D-Morphed Adipose-Cartilage Grafts Reconstruct Segmental Tracheal Defects Preclinically

Segmental tracheal defects from maxillofacial trauma or tumor resection pose life-threatening airway compromise, yet current grafts fail to replicate biomechanical and vascular complexity. This study pioneers a clinically scalable approach integrating 3D-printed biomimetic minichannels, minced cartilage granules (CGs), and adipose mesenchymal stem cells (ADSCs) to engineer vascularized tracheal substitutes for reconstruction. C-shaped polycaprolactone-polyglycerol sebacate scaffolds (4-layer coating) were fabricated via caramel-sacrificing 3D printing. Auricular/rib CGs (300–500 μm) from adult rabbits/minipigs were cryo-ground, mixed with ADSCs (3:1 ratio), and infused with platelet-rich plasma. Constructs were prevascularized subcutaneously (2 weeks) and orthotopically transplanted into 2 cm (rabbits, n=18) and 3 cm (minipigs, n=6) tracheal defects. Mechanical testing, proteomics, histology, and survival analysis were performed (ethics approval: No. 2023kq040). ADSCs enhanced chondrocyte survival by upregulating glycolysis (hexokinase activity: 65.02 ± 3.61 U/gprot vs. 46.22 ± 2.35 in hypoxia, p*<0.01), enabling rapid vascularization (CD31+ vessels: 24.67 ± 4.73 vs. 3.33 ± 1.15 in controls, p*<0.01). Grafts achieved native-level compressive strength (2.15 ± 0.11 N vs. 1.69 ± 0.15 N for native ) and maintained luminal patency for 67 days in rabbits, while porcine models showed 80% 8-week survival. This study establishes a critical breakthrough in oral and maxillofacial surgery, offering an emergency-compatible solution for both wartime and peacetime airway salvage. The dual role of ADSCs in metabolic reprogramming and angiogenesis sets a paradigm for reconstructing craniofacial defects.