Transplantation rejection concerns, and the need to find willing donors or to have others give consent ( for the deceased, in a cadaveric procedure ), and the need to match them and to screen the needed blood products and other materials and maintain sterility and asepsis, are all very relevant issues, as is how to proceed if rejection becomes an issue ( treatment, and if need be, removal ), and how to deal with immune suppression post-transplant ( this has become somewhat easier in recent years ).