Strategies to overcome the ABO barrier in kidney transplantation.
Kidney transplantation across the ABO blood group barrier was long considered a contraindication for transplantation, but in an effort to increase donor pools, specific regimens for ABO-incompatible (ABOi) transplantation have been developed. These regimens are now widely used as an integral part of the available treatment options. Various desensitization protocols, commonly based on transient depletion of preformed anti-A and/or anti-B antibodies and modulation of B-cell immunity, enable excellent transplant outcomes, even in the long-term. Nevertheless, the molecular mechanisms behind transplant acceptance facilitated by a short course of anti-humoral treatment are still incompletely understood. With the evolution of efficient clinical programmes, tailoring of recipient preconditioning based on individual donor-recipient blood type combinations and the levels of pretransplant anti-A/B antibodies has become possible. In the context of low antibody titres and/or donor A2 phenotype, immunomodulation and/or apheresis might be dispensable. A concern still exists, however, that ABOi kidney transplantation is associated with an increased risk of surgical and infectious complications, partly owing to the effects of extracorporeal treatment and intensified immunosuppression. Nevertheless, a continuous improvement in desensitization strategies, with the aim of minimizing the immunosuppressive burden, might pave the way to clinical outcomes that are comparable to those achieved in ABO-compatible transplantation.
Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
Georg A
GA
Böhmig
Section of Transplantation Immunology, Department of Surgery, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
Andreas M
AM
Farkas
Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
Farsad
F
Eskandary
Section of Transplantation Immunology, Department of Surgery, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
Thomas
T
Wekerle
D000017:ABO Blood-Group System / Q000097:blood; D000818:Animals; D001787:Blood Group Incompatibility / Q000097:blood / Q000276:immunology*; D003888:Desensitization, Immunologic; D004195:Disease Models, Animal; D006084:Graft Rejection / Q000276:immunology; D006801:Humans; D016030:Kidney Transplantation; D051379:Mice; D011183:Postoperative Complications / Q000276:immunology
D000017:ABO Blood-Group System