Transplantation of embryonic organs - kidney and pancreas.

One novel solution to the shortage of human organs available for transplantation envisions 'growing' new organs in situ via xenotransplantation of developing anlagen from animal embryos. We and others have shown that renal anlagen (metanephroi) transplanted into animal hosts undergo differentiation and growth, become vascularized by blood vessels of host origin and exhibit excretory function. Metanephroi can be stored for up to 3 days in vitro prior to transplantation with no impairment in growth or function post-implantation. Metanephroi can be transplanted across both concordant (rat to mouse) and highly disparate (pig to rodent) xenogeneic barriers. Similarly, pancreatic anlagen undergo growth, differentiation and secrete insulin in a physiological manner following intraperitoneal placement. Implantation of the embryonic pancreas, is followed by selective differentiation of islet as compared to acinar components. Here we review studies exploring the potential therapeutic use of embryonic kidney or pancreas transplantation.