Tissue-Engineered Allograft Tracheal Cartilage Using Fibrin/Hyaluronan Composite Gel and Its In Vivo Implantation

Objectives/Hypothesis: Treatment and management of tracheal defects remain challenging in head and neck surgery. Various reconstruction techniques have been used, with no consensus on the best approach. The purpose of this study was to explore a novel strategy to fabricate tissue-engineered trachea by using fibrin/hyaluronic acid (HA) composite gel and evaluate the feasibility of creating tracheal cartilage. Study Design: A preliminary animal experiment. Methods: Chondrocytes from rabbit cartilage were expanded and seeded into a culture dish at high density to form mechanically stable allograft tracheal cartilage using fibrin/HA composite gel. After a longitudinal cervical skin incision, the trachea was exposed and a rectangular defect (1 x 0.5 cm) was created on the cervical trachea by scalpel on six rabbits. Tissue-engineered cartilage using fibrin/HA composite was trimmed and fixed to defect boundaries with Tissucol (Baxter International, Deerfield, IL). Postoperatively, the site was evaluated endoscopically, histologically, radiologically, and functionally. Results: Postoperatively, rigid telescopic examination showed that the implanted scaffolds in all cases were completely covered with. regenerated mucosa without granulation or stenosis. Histologic data showed ciliated epithelium regenerated at the operated site from 2 months postoperatively. Ciliary beat frequency of ciliated epithelium on implants was very similar to normal respiratory mucosa. Computed tomography images revealed fine luminal contour of the regenerated site. However, allograft cartilage implanted was found to be partially preserved on the postoperative specimen. Conclusions: The tracheal luminal contour and functional epithelial regeneration without graft rejection and inflammation were observed after repair of a tracheal resection using allogeneic implants with chondrocytes cultured with fibrin/HA.