Future Therapy for End-Stage Renal Failure: Gene-Edited Pig Kidney Xenotransplantation

In patients with end-stage kidney disease, kidney transplantation from a living or deceased human donor offers a much-improved quality and length of life. Gene-edited pigs might provide an alternative source of kidneys for clinical transplantation (xenotransplantation). The major pathobiological barriers to successful pig kidney xenotransplantation have steadily been overcome by the following methods: (1) genetic engineering of the organ-source pig and (2) the administration of novel immunosuppressive agents. Pig kidney transplants have now supported immunosuppressed (anephric) nonhuman primates for periods in excess of a year, although this cannot be achieved consistently. The pig kidney graft can fulfill almost all of the functional requirements of a human kidney. The potential risks of infection with a pig microorganism will be minimized by the breeding and housing of the organ-source pigs in biosecure "clean" environments. For the first formal clinical trial, we suggest that diabetic patients on the waiting list aged 55-65 years with blood group O or B who are unlikely ever to receive a deceased human donor kidney might accept a pig kidney if it will negate the need for dialysis for 1 or more years.