Accommodation in renal transplantation: unanswered questions

Abstract

Accommodation, an acquired resistance of an organ to immune-mediated damage, has been recognized as an outcome of renal transplantation for more than 20 years. Accommodation was originally identified in blood group-incompatible kidney transplants that survived and functioned normally in recipients with high titers of antiblood group antibodies directed against antigens in the grafts. The most compelling questions today include how often and by which mechanisms accommodation occurs, and what might be the biological implications of accommodation. This communication summarizes recent advances in addressing these questions. Because its diagnosis has depended on identification of antidonor antibodies in serum, the prevalence of accommodation has been considered low. Recent research in animal models and clinical subjects may challenge that view. This research also suggests that sublethal graft injury of various types induces accommodation and that accommodation may be a dynamic condition, eventuating into tolerance on the one hand and chronic graft injury on the other. Burgeoning lines of investigation into accommodation now portray a condition of greater prevalence than once thought, exposing pathways that may contribute to the understanding of a range of responses to transplantation.