Progress in experimental intestinal transplantation in small animal models

The unique immune response after small bowel transplantation (SBT) has been the subject of extensive research using small animal models in rats and mi ce. These animals are inexpensive, for most societies ethically acceptable and the existence of inbred strains allows for reproducibility and defined immunobiological conditions. The basic immunological reactions, such as gra ft-versus-host-reactions (GVHR), host-versus-graft-reactions (HVGR), a comb ination of both reactions, chronic rejection and tolerance have been descri bed. Almost all immunosuppressive agents of proven or potential clinical re levance have been tested for their efficacy in small bowel transplantation. All techniques which are applied to intestinal transplantation in humans i ncluding multiorgan transplantation, can also be performed in rats. Intesti nal transplantation in mice is methodically restricted to heterotopic trans plantation. The mouse however, offers several advantages compared to the ra t model. A large number of congenic and knockout strains is available as we ll as many analytical tools. In the future, intriguing new insights into th e unique immunological mechanisms of allograft rejection will be discovered using murine models.