Complement-Binding and non-Binding HLA-DQ Antibodies after Renal Transplantation

Abstract

【Introduction】In the detection of HLA antibodies, it is a problem that the results of the FCXM (flow cytometric crossmatch test) and Luminex method (LABScreen Single Antigen IgG) conflict with the result of CDC-XM (complement-dependent cytotoxic crossmatch test). We have reported that the cause of this discrepancy is based on the difference in the complement-binding ability of HLA antibodies. We investigated about complement-binding of HLA-DQ antibodies after transplantation this time.【Method】We chose positive sera of Bcell antibodies from recipient’s sera which has passed for 4～11 years after transplantation, and detected HLA Class Ⅱ antibodies using LABScreen and C1qScreen. C1qScreen can detect complement-binding HLA antibodies. We studied about complement-binding DQ-DSA (donor specific antibodies) using these methods.【Results】It was only 4 recipients that only DQ antibodies were detected in 11 recipients of DQ antibodies positive of these objects. But 80% were DQ antibodies positive other 7 recipients, too, the 61% were C1qScreen positive. Complement-binding DQ-DSA don’t seem to influence the renal function after transplantation, although it is thought that complement-binding DSA (Class Ⅰ) are concerned with rejection.