Examination of the discrepancy of the results of FCXM and anti-HLA antibodies in ABO-incompatible kidney transplantation

Abstract

[Objective] In this study, we performed a fundamental investigation of the discrepancy of the results of flow cytometry lymphocyte crossmatch (FCXM) and FlowPRA (One Lambda Inc., Canoga Park, CA, USA) in ABO-incompatible kidney transplantation. [Method] We examined ABO-incompatible kidney transplantation cases with different results between FCXM and FlowPRA. We performed FCXM using untreated serum and absorbed anti-A or anti-B serum. Monoclonal anti-A and anti-B antibodies and anti-mouse IgM were used to confirm the existence of A and B blood group antigens. [Results] The false-positive reaction in FCXM disappeared with the absorbed anti-A or anti-B from recipient serum. Moreover, we detected the blood group A and B antigens on lymphocytes by binding anti-A and anti-B monoclonal antibodies to the lymphocytes. [Conclusion] Anti-A or anti-B antibodies affected the results of FCXM. We consider that we can accurately determine donor-specific anti-HLA antibodies (DSA) or anti-blood group antibodies by this method.