After serious infections, large airway defects are usually created in patients. It has been a major problem for medical experts because of the lack of adequate treatment methods. Several problems, which can be overcome by regenerative medicine, usually accompany treatment using tracheal resection. The tissue engineering techniques need a combination of cells, scaffold, and growth-regulation factors.
Since the proper treatment of tracheal defects has been challenging to clinicians and there has not been a consensus regarding the best approach to adopt, the hypothesis of the investigation was to find out an appropriate strategy in treating tracheal defects by the use of fibrin/hyaluronic acid (HA) composite gel.
The study was carried out by doing a preliminary animal experiment in which the chondrocytes from rabbit cartilage were expanded and seeded into a culture dish. It was done at high-density conditions, and it led to the formation of a mechanically stable allograft tracheal cartilage using fibrin/HA composite gel. It was followed by longitudinal cervical skin incision, exposure of the trachea, creation of a rectangular defect, and then the defect boundaries were filled with tissue-engineered cartilage.
After the site was evaluated postoperatively, careful examination revealed that the implanted scaffolds were entirely enveloped with the regenerated mucosa in the absence of granulation or stenosis. The histological assessment indicated that the ciliated epithelium rejuvenated after two months, while computer tomography images disclosed fine luminal contour of the regenerated site. On the other hand, the allografts that had cartilage showed signs of incomplete preservation on the postoperative sample.
Fibrin glue, blended with HA, used in the experiment had several beneficial attributes. Therefore, this blend provided a constructive environment for chondrocytes. They were then able to maintain their characteristics phenotype and synthesize cartilage ECMs. Allogeneic chondrocytes, because of their low antigenicity, can be used appropriately in treating cartilage tissue defects.