ABO blood type incompatible lung transplantation

ABO-incompatible transplantation has been successfully performed in the kidney and liver. However, lungs are subject to strong rejection and are vulnerable to infection because they are directly exposed to air. Therefore, lung transplantation from organs with incompatible blood types has been considered a significant challenge. Due to the severe shortage of donors, ABO-incompatible lung transplantation might be a viable method to save critically ill patients with end-stage respiratory diseases. Herein, we review the worldwide published reports about both minor and major ABO-incompatible lung transplantations. In North America, major ABO-incompatible lung transplants have been performed in cases with clerical errors in blood typing. But they were successful with additional treatments following the protocol for ABO-incompatible transplants in other organs (multiple plasma exchanges and additional immunosuppressive therapy such as anti-thymocyte globulin administration). In Japan, major ABO-incompatible living-donor lobar lung transplantations have also been performed successfully when the recipient does not have an ABO antibody against the donor. This unique situation sometimes occurs when the recipient undergoes hematopoietic stem cell transplantation before lung transplantation, in which the recipient’s blood type changes after hematopoietic stem cell transplantation. One infant and one adult had successful intentional major ABO-incompatible lung transplantation with both induction therapy and aggressive maintenance antibody-depletion therapy. Furthermore, an experimental antibody-depletion study has also been conducted to overcome ABO incompatibility. Even though intentional major ABO-incompatible lung transplantation has rarely been performed, several significant pieces of evidence have been accumulated to prepare for ABO-incompatible lung transplantation in selected cases. In the future, this challenge can potentially expand the donor organ pool and lead to improvements in the fairness of organ allocation.