In vitro construction of scaffold-free cylindrical cartilage using cell sheet-based tissue engineering.

Abstract

PURPOSE: Tissue-engineered cartilage may offer a solution for the treatment of serious airway disease. This study developed a novel procedure to fabricate a scaffold-free cylindrical cartilage under in vitro conditions, while also evaluating the effect of a dynamic culture on the engineered construct. METHODS: Auricular chondrocytes were harvested from New Zealand white rabbits and cultivated under high-density conditions to form a chondrocyte sheet. The sheet was looped around a silicon tube and cultivated for 6 weeks in dynamic or static conditions. The engineered cylindrical cartilages were evaluated macroscopically and histologically. The expression of collagen, glycosaminoglycan content and mechanical properties were determined. RESULTS: The cylindrical cartilage was sufficiently elastic and stiff to maintain the structure without disruption. Histologically, the construct contained a Safranin-O positive cartilaginous matrix accompanied by the expression of type II collagen. The glycosaminoglycan content increased and reached 72% of the native tracheal cartilage after 6 weeks of cultivation. CONCLUSION: A novel procedure was developed for fabricating engineered cartilage, which maintained the shape and a proper level of rigidity and flexibility, under in vitro conditions using sheet-based tissue engineering techniques. This procedure may allow for the development of a tailor-made autograft and a functionally engineered trachea.