ABSTRACT
This chapter focuses on how transgenic techniques might be applied to overcoming the hurdles to xenotransplantation posed by natural immunity. Transgenic animals have also been developed to address the problem of complement in xenotransplantation. The erythrocytes of the transgenic animals were shown to express the human proteins at a level comparable to the level in human erythrocytes. The cells of the transgenic mice were found to resist lysis by human complement. One effort to develop transgenic animals was that of D. White and colleagues who developed transgenic pigs expressing human decay accelerating factor (DAF) under control of the DAF promoter. The results of our initial studies involving the transplantation of organs from pigs expressing human complement regulatory proteins suggested that these proteins play a very important role in maintaining the integrity of a graft in the early post-transplant period and that the species specificity of the proteins is an important aspect of the susceptibility to xenograft rejection.
