Transmission of zoonoses in xenotransplantation: porcine endogenous retroviruses from an immunological and molecular point of view.

Background And Objectives: Pigs offer an unlimited source of xenografts for humans. The use of transplants from animal origin offers a potential solution to the limited supply of human organs and tissues. However, like many other mammalian species, pigs harbor porcine endogenous retrovirus (PERV), which are encoded in their genomic DNA and are assumed to have been integrated into the porcine germ line more than 7.