Research Projects

Several treatment methods for tracheal reconstruction have been developed, although reconstruction of critical sized defects (over 6 cm) is always a major challenge in trachea surgery. Use of prosthetic materials for tracheal reconstruction has been limited owing to infection, graft migration, ingrowth of fibrous tissue, and stenosis. Among various materials used for tracheal reconstruction, silicone is a better choice, owing to its biocompatibility, resiliency, mechanical integrity, nonreactivity in a biological environment (acid, alkali, enzyme or microbial attack) and low cost. The present study aims to prepare a silicone tube with a microporous surface by mold-casting technique, followed by immobilization of bioactive peptides with antimicrobial and anti-inflammatory properties. After evaluation of physicochemical (e.g., wettability), mechanical (e.g., compressive strength), and biological (e.g., in vitro cytocompatibility and cell adhesion) properties, inner surface of the silicone tube will be seeded with autologous nasal epithelial cells obtained from rabbit. Separately, adipose tissue-derived mesenchymal stem cells will be isolated from rabbit and differentiated to chondrogenic lineage, while forming cell sheet. The silicone tubes epithelialized at inner surface will be wrapped with cell sheet from outside and subcutaneously implanted in New Zealand white rabbits and examined for signs of infection of the prosthesis, inflammation, and biocompatibility at two-time points i.e., at 2 and 6 weeks. Based on biochemical and histologic assessments, the prefabricated grafts will be assessed for effectiveness of in vivo epithelium and cartilage tissue regeneration after orthotopic tracheal transplantation in rabbit partial resection model. After 2 and 3 months of implantation, graft integration with the surrounding host tissue, epithelial layer formation, absence of infection, inflammation, and fibrotic tissue formation will be evaluated through radiographic and histological procedures. The study will provide insight to the clinicians for the feasibility of utilizing prefabricated tracheal grafts overcoming challenges of infection, immune rejection and inflammation leading to granulation, and stenosis associated with post-implanted tracheal grafts.