Physiological aspects of xenotransplantation

Increasing efforts are being directed at providing solutions to the shortage of organs for allotransplantation. The immunological and infectious barriers to the use of xenografts have been extensively studied. However, physiological compatibility cannot be assured. A review of the physiological performance of clinical cases of renal, cardiac, and hepatic concordant xenotransplantation demonstrates some incompatibility between even closely related species. However, evidence from laboratory-based experiments suggests that a significant degree of physiological compatibility can be predicted for the transplantation of organs between discordant species. Preclinical studies involving genetically modified porcine hearts and kidneys transplanted into primate recipients demonstrate life-supporting function but also highlight interspecies differences that must be further studied before xenotransplantation can be a viable alternative to allotransplantation. Copyright © 2001 by W.B. Saunders Company.