TRACHEAL DECELLULARIZATION TISSUE ENGINEERING PROTOCOL FOR CIRCUMFERENTIAL TRACHEAL REPLACEMENT

The present invention concerns a new tracheal decellularization tissue engineering protocol for circumferential tracheal replacement, to develop a clinical grade partially tracheal decellularized matrix. The present invention finds its applications mainly in clinics, in particular in paediatrics.

The inventors developed a new partial decellularization tissue engineering protocol, using a porcine model, to develop a clinical-grade partially decellularized tracheal (PDT) matrix and validate the biointegration in vivo. Depending on the pathology, decellularized trachea could be used as a replacement or external reinforcement.

The detergent based treatment for decellularization is longer than Aoki's protocol but removes all the cells from the inner lining of the trachea, and is shorter than Lu and Liu’s protocols, to avoid damaging the extracellular matrix. The technique can also include a storage phase in a tissue bank. This long-term storage at -80°C or -196°C is widely used for biological tissues, and can facilitate clinical logistics and allow emergency surgery in a clinical setting.

After a thorough characterization of the final product: cell and DNA removal, sterility, toxicity, detergent quantification, biomechanical properties evaluation and in vivo study, the results showed that the final matrix was cell-free in the mucosa and the submucosa, while the less immunogenic cartilage was intact, maintaining the tracheal biomechanical properties and caliber. When implanted in vivo in a muscle for about one month, no systemic inflammation was observed, and the partially decellularized tracheal matrix showed excellent biointegration and vascularization, with no toxicity.