Transgenic human decay accelerating factor makes normal pigs function as a concordant species.

Our experiments indicate a crucial role of DAF in preventing rejection in discordant species combinations. Transgenic human DAF seems to inhibit successfully complement-mediated damage to the endothelial cell, thus preventing endothelial activation and consequently myocardial damage. Transgenic human DAF makes a discordant species (pig) function as a concordant species, that is, hyperacute rejection does not occur.