A comparison of enzyme-linked immunoabsorbent assays and flow cytometry techniques for the detection of HLA specific antibodies

LATM, Quikscreen (QS), and B-Screen (QSB) are ELISA-based tests for the detection of HLA specific antibodies. FlowPRA beads are microparticles coated with HLA antigens for the detection of HLA specific antibodies by flow cytometry. The aim of this study was to evaluate the sensitivity and specificity of the LATM, QS, QSB, and FlowPRA screening tests. One hundred sixty-three sera from renal transplant patients were tested using LATM, FlowPRA, QS, and QSB. Discrepant results were further investigated using complement dependent cytotoxicity, QuikID, and PRA-STAT. When QS was compared with LATMI and FlowPRAI for the detection of HLA class I specific antibodies the overall concordance was 82.8% with no particular specificity missed by any one test. Comparing QSB with LATMII and FlowPRAII, for the detection of HLA class II specific antibodies, there was 90.7% concordance. Although the overall concordance was better for class II specific antibodies, QSB failed to detect antibodies to HLA-DQ in a number of samples from different patients. Of the methods tested, flow cytometry using FlowPRA beads appeared to be the most sensitive and specific, missing the least number of specificities. However, the ELISA methods offer the advantage of being more suitable for testing large numbers of samples in a more time- and cost-effective manner. (C) American Society for Histocompatibility and Immunogenetics, 2001. Published by Elsevier Science Inc.