Development of a mouse model for heterotopic limb and composite-tissue transplantation

The mouse remains the most suitable model to study the complexities of the immune system and transplant rejection. The purpose of this study was to describe a new mouse model for heterotopic limb and composite tissue transplantation. Eighteen procedures were performed, including 10 heterotopic lower hind limb, four vascularized skin, and four vascularized muscle transplantations. Three transplants were allogeneic, and the rest were syngeneic. All successful syngeneic transplants were harvested at 11 days postoperatively, except for one skin and one limb transplant that were followed for over 30 days. The allogeneic transplants showed signs of rejection between 7 to 11 days postoperatively. Results of mixed lymphocyte culture (p < 0.05) and histology evaluations from the allogeneic recipients were consistent with acute rejection as the cause of allograft loss. The mortality rate was 16.7 percent, and the overall success rate was 72.2 percent. Details of the operative procedure are described, and important technical factors are discussed.