Development of a mouse intestinal transplantation model.

We have recently developed a mouse intestinal transplantation model. The proximal segment of donor jejunum is transplanted into the recipient in a heterotopic position. End-to-side anastomoses are performed between donor aorta and recipient aorta and between donor portal vein and recipient inferior vena cava. Mortality rates were initially high due to shock, arterial thrombosis, and postoperative sepsis. Refinements in surgical techniques reduced these complications, resulting in a high rate of success. Important technical factors included (1) minimizing ischemic injuries to the graft in both the donor and the recipient, (2) using an aortic patch and elliptical aortotomy for anastomosis, (3) administering large volumes of crystalloid to maintain normal blood pressure during the donor and recipient surgeries, and (4) using broad-spectrum antibiotics as postoperative prophylaxis. The mice with isografts had normal intestinal function and histology when they were sacrificed 1 month after surgery. This new model of small bowel transplantation will be a useful tool to study the immunology of intestinal grafting at the molecular level.