Scaffold-Free Tracheal Cartilage Engineering Using Roller Bottle Culture

Resection with primary anastomosis can only repair up to 50% of the adult trachea and up to 30% of the pediatric trachea when damaged. There is a strong clinical need for long-segment tracheal replacements. The goal of this research was to create a seamless, scaffold-free cartilage cylinder for tracheal tissue engineering in vitro. Primary bovine articular chondrocytes were seeded onto tracheal moulds for roller bottle culture and the effect of rotational speed, growth factor supplementation, and chondrocyte layering were investigated. After the 4-week culture period, samples were evaluated biochemically, histologically, and biomechanically. The results indicated that rotation was necessary for full tissue coverage, with slower rotational speeds generating thicker tissue with an improved extracellular matrix, IGF-1 supplementation generating thicker tissue rich in glycosaminoglycans with inferior mechanical properties, and chondrocyte layering producing thinner tissue with increased mechanical properties. Overall, scaffold-free tissue engineering can generate seamless cylindrical cartilage constructs using roller bottle culture for future applications in long-segment tracheal replacement.