Optimized technique for experimental multivisceral transplantation

There has been a shift toward combined liver-intestine and multivisceral transplantation (MVT), whereas isolated intestinal transplantation has taken a backseat, mainly because of its higher rejection rates. Despite this, experimental models tend to focus on intestinal transplantation or isolated liver transplantation, likely because of the technical complexity of MVT. This study aimed to outline a refined surgical protocol for MVT in rats.

Syngeneic heterotopic MVT was performed in five Sprague-Dawley rat under sevoflurane anesthesia. The grafts included liver, stomach, pancreas, and small bowel tissues. These were anastomosed en bloc, end-to-end, to the infrarenal vena cava and aorta.

A 100% survival rate was achieved. Initially, the clinical discomfort scores increased during the first 48 h but gradually improved by days 6-7, coinciding with weight recovery and normalization of behavior. Histological analysis revealed preserved architecture of the stomach, pancreas, and native organs. The intestinal tissue remained largely unchanged, with mild villous tip edema noted in one case. One grafted liver showed necrosis and hemorrhage, whereas the remaining grafts were viable, with mild congestion in two cases. Biochemical analyses revealed normal levels of total bilirubin, gamma-glutamyl transpeptidase, lipase, urea, and creatinine. Aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase levels were elevated, but none reached statistical significance when compared with the pre-transplant values.

This model offers a dependable and reproducible platform for experimental MVT, providing a well-documented and accessible tool to encourage the incorporation of MVT into current translational and immunological research.