Effect Of RhBMP-2 On Rabbit Tracheal Reconstruction By Inducing Ectopic Cartilage Regeneration

Clinically, total or partial loss of tracheal cartilage induced by tumor and trauma will lead to collapse of the anterior wall of the trachea and airway stenosis, resulting in respiratory obstruction. It is a serious life-threatening disease which has caused great burden on patients and society. Traditional treatment mainly focused on submucosal scar resection, tracheal dilatation, tracheal stenosis resection anastomosis or autologous or allogeneic tissue laryngotracheal reconstruction. However, myocutaneous rotary door Flap can not be used on some severe cervical skin scar. Seeding in vitro cultivated cells into the three-dimensional scaffolds and transplanting them after proliferation to reconstruct tracheal defect always not able to meet the requirements of practical application due to structural defects. In recent years, tissue engineering techniques and materials progress allowed application of rhBMP-2 induced muscle mesenchymal stem cells to cause ectopic cartilage cell regeneration, consequently to widen, support and repair the defective anterior wall of the trachea. rhBMP-2 might increase muscle strength, and thus support the tracheal collapse, keeping the air passage open. Because what it induced are autologous mesenchymal stem cells which have rich sources, it may reconstruct tracheal defect in a more easy way.ObjectiveTo investigate the feasibility of using recombined human bone morphogenetic protein-2 (rhBMP-2) to induce regeneration of ectopic cartilage and to reconstruct rabbit tracheal defect.Methods24 New Zealand rabbits were used in this experiment. A 1/3 defect of cartilage in the anterior ward of the trachea of the animal was created. Rabbits were randomly divided into two groups (n=12).The tracheal defect was repaired by anterior cervical muscle and injected with rhBMP-2 and absolute alcohol separately. The specimens were procured at 4,6,12 weeks for general observation and HE staining in order to evaluate the reconstruction.ResultsRabbits of the experimental group are all survived. In control group, some animal were died of infection and ischesis, while subcutaneous emphysema and choking were observed in other rabbits. ConclusionrhBMP-2 can reconstruct rabbit tracheal defect and maintain the tracheal shape, consequently decrease the incidence of subcutaneous emphysema and choking and has potential clinical application.