PROSPECTS FOR XENOGRAFTING

New insights into the mechanisms of hyperacute rejection, endothelial cell activation and accommodation are clarifying the processes that de termine the rejection of discordant xenografts. Recent advances includ e the identification of endothelial cell antigens targeted by human an ti-pig antibodies and an increasing understanding of the mechanisms un derlying endothelial cell activation. Novel ways to prevent hyperacute rejection, including new therapeutic agents and the use of organs fro m transgenic animals, are promising to significantly improve the early survival of pig organs transplanted into man. Clinical xenotransplant ation has become a realizable goal.