Moving the Margins: Updates on the Renaissance in Machine Perfusion for Organ Transplantation

Abstract

Escalating end-organ disease coupled with stagnant donor pools has begotten global organ shortages. Ex vivo organ perfusion, used briefly in the early days of clinical transplant and then sidelined for decades by static cold storage, has resurged to address this organ paucity. Given the recent prolific application of machine perfusion as a platform for assessment, preservation, and treatment of marginal grafts, this review summarizes salient results from the past 2–3 years in kidney, liver, lung, heart, pancreas, vascularized composite allograft, and xenograft transplantation. Clinical trials have established the ability of ex vivo perfusion to make previously declined thoracic and abdominal organs transplantable without sacrificing short- or long-term function and survival. In addition to extended assessment and superior preservation, machine perfusion enables targeted delivery of cutting-edge gene and immunomodulatory therapies. At the leading edge, ex vivo perfusion has recently led to breakthroughs in xenotransplantation, enabled ischemia-free liver transplants, and been incorporated into out-of-hospital organ resuscitation centers. Ex vivo machine perfusion is transitioning from being dormant to indispensable in clinical organ transplantation. Providing a platform for extended assessment, superior preservation, and targeted therapy, ex vivo organ perfusion can make marginal, previously declined organs a part of the donor pool. Pioneering pre-clinical studies continue to provide guidance on how to optimize and leverage this invaluable system for further expansion of lifesaving organ transplantation.