Tracheal Reconstruction Using Hybrid Decellularized-Pcl Scaffolds: Two-Stage Heterotopic and Orthotopic Transplantation Publisher



Moaveni AK ; Ghorbani F ; Dezfouli MM ; Sadr M ; Safshekan F ; Shadmehr MB ; Kajbafzadeh AM
Source: Regenerative Engineering and Translational Medicine Published:2026

Abstract

Background: Long-segment tracheal defects remain a significant surgical challenge that cannot be treated with conventional tracheal resection and anastomosis. Current treatment options have limitations; autologous tissues are inadequate, long-term endotracheal stenting is associated with complications, allografts require immunosuppression, and existing tissue engineering solutions have advantages and also drawbacks. This study investigates an approach combining a hybrid scaffold with a two-stage surgical strategy for tracheal reconstruction. Methods: Hybrid scaffolds were fabricated by combining decellularized rabbit tracheal matrix with polycaprolactone (PCL) stents. Eighteen New Zealand white rabbits were used for protocol optimization, heterotopic transplantation, and orthotopic transplantation. The decellularization protocol involved 48-h treatment with 1% sodium dodecyl sulfate, followed by DNase I and Triton X-100 treatment. A two-stage surgical approach was employed: heterotopic pre-vascularization in the sternocleidomastoid muscle for 15 days, followed by orthotopic transplantation to repair 1.5 cm segmental tracheal defects. Scaffold characterization included DNA quantification, biomechanical testing, and histological evaluation using H&E, Masson's trichrome, and immunofluorescence analysis for CD31, CD68, and CK5 markers. Results: The decellularization protocol achieved 98.3% DNA reduction (p < 0.001) with preserved mechanical properties. All rabbits (n = 6) survived heterotopic transplantation, with 15-day implants showing optimal tissue integration. Seven of eight rabbits survived orthotopic transplantation, with one animal monitored for 72 days. Histological analysis revealed progressive tissue regeneration: CD31 expression increased significantly in decellularized scaffolds in heterotopic implants, indicating successful revascularization. CK5-positive epithelial cells increased in orthotopic implants significantly, demonstrating epithelial regeneration. Conclusion: This study demonstrates the feasibility of a two-stage approach using a hybrid scaffold for tracheal reconstruction. The combination of PCL reinforcement with decellularized matrix, coupled with heterotopic pre-vascularization, provides a promising strategy for treating long-segment tracheal defects. Further studies with large animal models, larger sample sizes, and longer follow-up periods are warranted to validate these findings. Lay Summary: The trachea can be damaged by disease, injury, or birth defects, creating breathing difficulties that are challenging to repair surgically. Current treatments have significant limitations and complications. This study developed a new approach using a hybrid scaffold made from processed animal trachea tissue combined with a biodegradable support structure. The researchers used a two-stage surgical technique: first implanting the scaffold in neck muscle to grow blood vessels, then moving it to replace the damaged trachea section. Testing in rabbits showed successful tissue regeneration with new blood vessels and breathing cells growing into the scaffold, demonstrating a promising new treatment option. Future Works: Future research should focus on larger animal models with extended follow-up periods to assess long-term outcomes and complications. Studies should investigate improved scaffold designs, alternative biomaterials, and less invasive monitoring techniques. Clinical translation will require optimization of sterilization protocols, standardization of surgical procedures, and comprehensive safety evaluations before human trials. © The Author(s), under exclusive licence to The Regenerative Engineering Society 2026.