ABSTRACT
Xenotransplantation is de¢ned as “any procedure that involves the direct transplantation, implantation, or infusion into a human recipient of live cells, tissues, or organs from a nonhuman animal source; or indirect exposure, where human body œuids, cells, tissues, or organs that have had ex vivo contact with live nonhuman animal cells, tissues, or organs are administered” [1]. Obviously, the ¢rst part of this de¢nition has received most attention as it directly relates to an alternative to human cells, tissues, or organs in treatment of patients with end-stage organ disease. The second part relates to, for example, vaccine production using cultures of xenogeneic cells and will not be further discussed in this chapter.
