Abdominal organ cluster transplantation in pigs and FK506.

Using a swine abdominal organ cluster transplantation model, we investigated the postoperative function and immunological reactions of a cluster graft and evaluated the immunosuppressive activity of FK506. The animals were divided into two groups. Group I (n = 6) served as controls, while in group II (n = 6) a daily dose of 0.1 mg/kg FK506 was given intramuscularly. Postoperative pancreatitis was the most important factor influencing the early outcome in both groups. In group I, the cause of late death was cachexia due to diabetes mellitus induced by pancreatic rejection. In group II, emaciation despite a well-functioning graft was the principal cause of late death. Histologically, in group I the grade of rejection in the pancreas was more severe than in the liver, and no sign of rejection was observed in group II. In conclusion, the pancreas suffered more severe rejection than the liver, and FK506 could significantly prevent cluster allograft rejection in this model.