Genetically modified pigs as donors of cells, tissues, and organs for xenotransplantation

Implications • For many patients with chronic organ failure, transplantation is the only therapeutic option, but the number of donated human organs and tissues falls far short of the need. • Porcine cells, tissues, and organs likely will be an alternative transplant source, since pigs can be genetically engineered to overcome rejection mechanisms and physiological incompatibilities, and to reduce the risk of transmitting zoonotic pathogens. • Significant progress has been made in many areas of xenotransplantation, including pancreatic islets, neuronal cells, and corneas, but also vascularized organs, especially kidneys and hearts. • In view of recent preclinical breakthroughs, such as consistent long-term survival of baboons after orthotopic transplantation of a genetically multimodified porcine heart, xenotransplantation can be considered as a realistic future therapeutic option.