Developments in kidney xenotransplantation.
Genetically modified pig kidneys have moved from non-human-primate models into pig-to-human studies, with recent decedent transplants demonstrating life-sustaining function for weeks while antibody-mediated and T cell-mediated rejection remain the central barriers.
Background
The scarcity of human donor kidneys for patients with end-stage kidney disease has driven decades of work on xenotransplantation using genetically engineered pigs. Advances in CRISPR-Cas9 gene editing have allowed deletion of xenoantigens (such as the alpha-1,3-galactosyltransferase/GGTA1 product) and insertion of human protective transgenes, substantially reducing the risk of hyperacute rejection.
Key recommendations
Reported decedent and preclinical experience indicates that gene editing alone does not overcome all xenogeneic immune barriers. Studies describe early antibody-mediated rejection, microvascular inflammation, and infiltration by natural killer cells and macrophages despite knockout of major xenoantigens, with reactivation of porcine cytomegalovirus/roseolovirus noted in some grafts. These findings point to the need for tailored immunosuppression, possibly including CD40-CD154 costimulation blockade, robust pathogen screening, and extended observation in decedent models before broader clinical use.
Clinical implications
One reported pig-to-human decedent kidney xenotransplant achieved hemodynamic and electrolyte stability and dialysis independence over a pre-planned multi-week study, with an episode of antibody-mediated rejection reversed by plasma exchange, complement inhibition, and anti-thymocyte globulin. While such results show that minimally gene-edited pig kidneys can support life-sustaining function in humans, pre-existing xenoreactive T cells and induced antibodies, infection risk, and ethical considerations mean continued research is required before xenotransplantation becomes an established therapy.
Category
Transplant
Source
Front Immunol
More from ASNRT News
Browse the latest news, society announcements, KDIGO guideline updates, and AJNT issue releases on the ASNRT newsroom.