Healing of bronchial allografts in pigs

Our purpose was to investigate the healing of bronchial grafts in a porcine experimental model. Via left thoracotomy, a 2.5 cm long bronchial stump wa s anastomosed back to the same animal (autograft) or to another pig (allogr aft). Autotransplanted bronchi (six pigs) healed very well without infectio n. Allotransplantation without immunosuppression (eight pigs) was followed in all cases by rejection with formation of major bronchopleural fistula. A fter allotransplantation with triple-drug immunosuppressive medication (sev en pigs), three pigs showed infection-free healing, but the anastomoses wer e slightly stenosed at the time of sacrifice (mean 30 d), while four had br onchopleural fistula. The study thus showed the healing ability of totally avascular bronchial graft in pigs to be very good when it is autotransplant ed, but poor when allotransplanted without immunosuppressive treatment.