Antibody Responses in Immunosuppressed Organ Allograft Recipients - Brief Review of the Current Literature

With the rapidly growing application of new highly sensitive techniques for detection and definition of antibodies specific to HLA and non-HLA antigens, a significant number of studies have reported that de novo generation of antibodies after organ transplantation is associated with severe immunological complications and graft loss. The presence of donor specific complement-binding antibodies is confirmed by the finding of C4d deposits in the peritubular capillaries of the kidney graft - a method now regularly used as a marker of antibody-mediated rejection. The clinical significance of various techniques for antibody identification with respect to the incidence of organ transplant rejection is however still a matter of discussion. The discrepancies in the literature are most likely caused by variations in the approaches for antibody characterization and differences in patient cohorts and immunosuppressive protocols. In this concise review, we will discuss some recent developments in the study of the role of antibodies specific to HLA and non-HLA antigens for the occurrence of cellular and antibody-mediated rejection after organ transplantation.