Continuous Monitoring of Donor Specific Anti-HLA Antibody in Kidney Transplantation Patients

Abstract

Background: A positive reaction at flow cytometry crossmatch (FCXM) has been highlighted by its predictive value for clinical outcome in kidney transplantation after accumulation of large clinical data. The detection of de novo development of anti-HLA antibodies after transplantation is associated with increased rejection and decreased graft survival. In this study, we report the experience for the detection of anti-donor specific antibody (DSA) by more sensitive FCXM methods in renal transplantation patients.Methods: T and B cell FCXMs were performed on 11 pretransplant and 51 posttransplant sera from 11 patients who received renal grafts between 2004 and 2005. The posttransplant sera were collected in specific and regular intervals from posttranspant 1 week to 1 year.Results: Among 62 sera, four (7.8%) from 2 patients showed positive FCXM. In one patient, pretransplant serum which was negative at previous CDCXM, and 2 consecutive sera collected at 1 week and 1 month after transplantation were positive at FCXM. And the antibody identified was B51 which was specific for one of donor alleles (DSA). In another patient, FCXM became positive 1 week after transplantation although pretransplant serum had negative results at both CDCXM and FCXM. Both patients had experienced more than one rejection episodes.Conclusions: Detection of DSA with more sensitive technique such as flow cytometry based method clearly displayed a beneficial effect for prediction of clinical outcome as a part of pretransplant compatibility test, and also as a posttransplant monitoring test to identify the de novo production of clinically significant DSA.

HLA antibody screening strategy in patients awaiting kidney transplantation

“…Therefore, we consider this complementary strategy, which includes useage of both CDC and ELISA techniques, simultaneously or alternatively, as appropriate and useful for HLA antibody screening in all pretransplant patients, since it provides the advantages of both of techniques, in conjunction. Our data are in agreement with other reports [18,[23][24][25], that also confirmed the higher sensitivity and greater ability to detect antibodies by ELISA technique in comparison to CDC. This discrepancy of positive test results obtained only by ELISA 121 (19.96%), in comparisom to the positive results obtained only by CDC test 64 (10.56%), could be explained by either a greater sensitivity of the ELISA or to the presence of noncytotoxic antibodies which CDC method could not detect.…”

“…The association between antibody response and acute immunological complications after transplantation has been under intense investigation in recent years [14,18,19]. The introduction of new technologies such as ELISA, flow cytometry and Luminex, has provided alternative methods to complement dependent cytotoxicity test for HLA specific antibody detection [20][21][22].…”