Differences in anti-CREG antibody formation between transplanted and nontransplanted renal patients

Background The aim of this study was investigation of the HLA-I cross-react ive group (CREG)-specific antibodies (Abs) in sera from patients with a fai led renal transplant and from nontransplanted patients. Methods. A total of 5292 sera from 570 patients awaiting kidney transplanta tion were screened for the presence of HLA-I CREG-specific Abs, Patients wh o had never received a transplant (group A), and those with a previous tran splant and Abs either not related (group B) or related to donor specificiti es (group C) were studied. A further division was made for Abs directed aga inst specificities either included in (intra-CREG) or not included in patie nts' HLA-CREG (extra-CREG). Results. Twelve of 24 (50%) Abs produced in response to mismatched donor HL A specificities after a failed graft were intra-CREG Abs, compared to 7 of 39 (18%) Abs that were not transplant-related. Conclusions. Renal grafts showed a stronger immunogenicity than other sourc es of allosensitization. Our data also suggest that CREG matching may not b e useful for renal allocation.