LAUSR

OBJECTIVES In this study, we examined the quantitative significance of humoral immunity by flow-cytometric crossmatch using molecules of equivalent soluble fluorochromosome (FCXM-MESF) in recipients of kidney transplantation. We stratified the recipients into four sensitization classes, from non-sensitized to strongly sensitized by the results of the FCXM-MESF assay, and compared the pathological results after transplantation by the sensitization status. MATERIALS AND METHODS We stratified 140 recipients into four groups according to their sensitization status, as follows; none/NDSA, defined by FCXM-MESF values of below the cut-off value (n = 79), mildly sensitized, defined by FCXM-MESF values of less than 3000 (N = 45); moderately sensitized, defined by FCXM-MESF values of between 3000 and 8000 (N = 12); strongly sensitized, defined by FCXM-MESF values exceeding 8000 (N = 4). RESULTS We employed tailor-made immunosuppressive regimens according to the FCXM-MESF values for the 140 recipients between 2009 and 2011. In regard to the pathological results, 4% (2/51), 3% (1/35), 20% (2/10) and 75% (3/4) of the none/Non Donor Specific Antibody (NDSA), mildly sensitized, moderately sensitized and strongly sensitized patients showed antibody mediated rejection (AMR). Thus, FCXM may be more useful for the detection of anti-non-HLA as well as for that of anti-HLA antibodies than the solid phase assay (SPA) or panel reactive antibody (PRA) assay. CONCLUSION Quantitative analysis using FCXM-MESF assay accurately reflected the clinical as well as pathological aspects, and may serve as a useful guide for the selection of appropriate anti-rejection therapy.