Segmental small-intestinal transplantation: a comparison of jejunal and ileal grafts.

Strong immune responses, such as rejection and graft-versus-host disease, have been major obstacles to achieving a successful intestinal transplantation. Segmental small-intestinal transplantation is considered to result in a weaker response than total length grafting. Problems relating to organ harvesting from a living donor and spacial constraints of the recipient's abdominal cavity are the other reasons why a segmental small intestinal transplantation is required. It is also important to select the most suitable part of the intestine to be used in transplantation; therefore, the jejunal and ileal grafts were comparatively reviewed from the aspects of native bowel characteristics, function, preservation, and immunological response. Immunologically, the jejunum is considered to have a slight advantage over the ileum. However, the control of rejection does not become inordinately more difficult for ileal grafts. Functionally, the ileum is considered to be better with regard to several parameters, such as greater absorptive capacities of fat, bile acids, and vitamins, and adaptation potential. Anatomically, an ileal graft is feasible for living-related transplantation. However, there is no conclusive factor for choosing the ileum as a suitable segmental graft. Further extensive studies are still needed to clarify various experimental as well as clinical aspects regarding intestinal transplantation.