COMPARISON OF PRA-STAT, SHLA-EIA, AND ANTI-HUMAN GLOBULIN-PANEL REACTIVE ANTIBODY TO IDENTIFY ALLOREACTIVITY IN PRETRANSPLANTATION SERA OF HEART-TRANSPLANT RECIPIENTS - CORRELATION TO REJECTION AND POSTTRANSPLANTATION CORONARY-ARTERY DISEASE

Background: Screening pretransplantation recipient sera for percent pa nel reactive antibodies (%PRA) by an anti-human globulin (AHG) assay m ay identify recipients who are at risk for graft rejection or developm ent of posttransplantation coronary artery disease. However, the pretr ansplantation AHG-%PRA does not always correlate with the occurrence o f graft rejection or coronary artery disease. Methods: We compared the predictive capacity of the AHG-%PRA with that of an enzyme-linked imm unoassay (EIA)-based PRA assay that identifies immunoglobulin G bound to soluble human leukocyte antigen (sHLA) class I molecules from poole d platelets of 240 random donors (sHLA-ELA), and that of an EIA-based assay that detects immunoglobulin G anti-HLA class I antibodies bound to sHLA derived from individual HLA-typed cell cultures (PRA-STAT). Th e pretransplantation sera from 130 cardiac allograft recipients were c omparatively tested and results evaluated. Results: Although AHG-%PRA- and sHLA-EIA-determined PRA results were comparable, neither assay di scriminated potential recipients at risk for rejection or coronary art ery disease. However, cardiac allograft recipients with pretransplanta tion PRA-STAT sera > 10% were at risk for(1)graft rejection (77% vs 56 %, p <.05); (2) more rejections/recipient (1.9 vs 1.0, p <.02); (3) gr aft rejection within 30 days (92% vs 38%, p <.001); or (4) development of coronary artery disease (48% vs 23%, p <.05) than recipients with pretransplantation PRA-STAT sera < 10%. Conclusions: PRA-STAT analysis of pretransplantation sera from potential cardiac allograft recipient s may be more clinically informative about HLA alloimmunity and a bett er predictor of adverse clinical events than either AHG-%PRA- or sHLA- EIA-determined PRA.