Analysis of preformed donor-specific anti-HLA antibodies characteristics for prediction of antibody-mediated rejection in kidney transplantation

作者：Malheiro Jorge^*; Tafulo Sandra; Dias Leonidio; Martins La Salete; Fonseca Isabel; Beirao Idalina; Castro Henriques Antonio; Cabrita Antonio

来源：Transplant Immunology, 2015, 32(2): 66-71.

DOI：10.1016/j.trim.2015.01.002

• Antibody-mediated rejection
• Donor-specific antibody
• Graft survival
• Kidney transplantation
• Single-antigen bead assay

Background: The relevance of preformed donor specific antibodies (DSA) detected by Luminex assays, with a negative complement-dependent cytotoxicity (CDC) crossmatch, remains unsettled in kidney transplantation (KT). We aimed to analyze the impact of preformed DSA characteristics on kidney graft outcomes.
Methods: In 462 patients that received a kidney graft in our unit, between 2007 and 2012, pre-transplant sera were analyzed by Luminex screening assay to determine the presence of anti-human leukocyte antigen (HLA) antibodies and single-antigen bead assay [positive if mean fluorescence intensity (MFI) >= 1000] to assign anti-HLA specificities.
Results: Anti-HLA antibodies were present in 95 patients (20.6%), but only 40 (8.7%) had DSA. Antibody-mediated rejection (AMR) at 1-year was higher in patients with DSA (35.0%) than in those without them (0.9%) (P < 0.001). Only DSA with a MFI of >3000 were significantly associated with AMR occurrence. Receiver operator curves revealed that a MFI of >4900 in the highest DSA bead had a high sensitivity (85.7%) and that the sum of all DSA beads MFI > 11,000 had a high specificity (92.3%) for AMR prediction. Anti-thymocyte globulin versus basiliximab induction was more frequent in DSA + AMR - (65.4%) versus DSA + AMR + (34.6%) patients (P = 0.072). Five-year censored graft survival was lower in DSA + than in DSA - patients (respectively, 84.8% versus 94.9%, P = 0.006), although survival was only reduced in DSA + AMR + (68.8%) versus DSA + AMR - (96.0%) patients (P = 0.038).
Conclusions: Preformed DSA is associated with kidney graft loss, in relation with AMR occurrence. DSA strength may be used to improve immunological risk stratification of sensitized patients and their clinical management.

• 出版日期2015-3