This study evaluated the feasibility of the xenotransplantation of the trachea in the pig to the trachea in the dog to help solved the partial problem of the recipient trachea. Three healthy beagle dogs weighing between 9~10 kg were used as recipients and three pigs weighing 20 kg were used as donors. Two cm x 2 cm quadrate tracheal section was resected from each recipient, and tracheal xenotransplantation were performed. All animals were carefully monitored during 6 months of the observation for anatomic complication or infection. The recipients were sacrificed at 6 months after operation the grafts were assessed. All of the dogs survived the operation, and all of their wounds heals well. On bronchoscopy, airways were open and no stenosis or malacic changes were seen in the canine trachea. At the one month after xenotransplantation, the white xenograft was exhibited in the surface airway epithelium after xenotransplantation. At the 2 months after xenotransplantation, the xenograft was covered by mucous membranes. At the 3 months after xenotransplantation, the airway epithelium was normally regenerated. The levels of IL-2 and IFN-γ were significantly increased at the 7 days after xenotransplantation. The results of the polymerase chain reaction showed that tissue component from pigs could be identified in the xenograft of the beagle. The tracheas at 6 months post-transplantation were performed with immunohistochemistry-diaminobenzidine stain. They were stained for cluster of differentiation 3 (CD3) T-lymphocytes, CD4 plus T-lymphocytes, CD8 plus T-lymphocytes and CD20 plus B-lymphocytes. The tracheas were observed the rest of the immune cells (CD4 plus T-lymphocytes, CD8 plus T-lymphocytes and CD20 plus B-lymphocytes) that was intact so there is almost no difference between the normal and transplantation trachea. The blood vessel and the epithelium of the tracheal lumen in dogs were regenerated. Dogs were showed normal breathing and activity at two weeks post-transplantation. At the 3 months post-transplantation, the airway epithelium was normally regenerated. In this study, the porcine tracheal section was successfully xenotransplanted into the trachea of the recipient Beagle. Although this experiment is successful, but need a study about xenotransplantation in a large part to a variety of applications. Key words: xenotransplantation, pig, trachea, dog
This research was supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, Republic of Korea.