Kasra Shirini, Joseph M Ladowski, Niket Harsh, Raphael P H Meier
In the first half of 2026, xenotransplantation advanced through refinement rather than dramatic new clinical milestones. Clinical studies described graft physiology, immune infiltration, complement activation, coagulation incompatibility, and early function in living recipients, decedent models, and clinical islet xenotransplantation, including the first orthotopic multi-organ decedent xenotransplantation model. Additional preclinical studies in pigs and nonhuman primates on kidney, heart, islets, and blood product models used more advanced engineering of donor organs, including up to ten genetic edits. They identified persistent issues such as thrombotic microangiopathy, renin-angiotensin-aldosterone system dysregulation, and hemolysis-induced ferroptosis. Translational advances in xenotransplantation included the Banff guidelines for xenograft pathology, detection of cell-free DNA derived from the donor, complement, better histocompatibility tests, improved immunosuppressive approaches, and biosafety considerations.