A bioengineered trachea-like structure improves survival in a rabbit tracheal defect model.

Area of Science:

• Biomaterials Engineering
• Regenerative Medicine
• Tissue Engineering

Background:

• Tracheal reconstruction remains a significant clinical challenge.
• Current methods for tracheal repair or replacement have limitations.
• A need exists for functional, bioengineered tracheal substitutes.

Purpose of the Study:

• To develop a bioengineered trachea-like structure for potential clinical application.
• To evaluate the biocompatibility, vascularization, and mechanical properties of the engineered construct.
• To assess the in vivo efficacy of the bioengineered trachea in a rabbit model.

Main Methods:

• Fabrication of bioengineered cartilage (BC) rings using 3D-printed poly(ɛ-caprolactone) (PCL) fibers and rabbit chondrocytes.
• Assembly of trachea-like structures by alternately stacking PCL fiber-hydrogel and BC rings on silicone tubes.
• Heterotopic transplantation in rabbits to assess vascularization (4 weeks).
• Orthotopic transplantation following tracheal resection to evaluate functional integration and survival (8 weeks).

Main Results:

• The bioengineered cartilage formed a composite structure mimicking native cartilage ECM deposition.
• Engineered trachea constructs exhibited successful vascularization after heterotopic transplantation.
• Orthotopic transplantation demonstrated comparable mechanical properties to native rabbit trachea.
• High survival rate (83.3%) and preserved respiratory function were observed in transplanted rabbits.

Conclusions:

• The developed bioengineered trachea-like structure shows promise as a functional tracheal graft.
• The composite PCL-chondrocyte scaffold supports vascularization and mechanical integrity.
• This approach offers a potential solution for treating tracheal stenosis and injuries.