De Novo Donor-Specific Anti–Human Leukocyte Antigen Antibody Detection in Long-Term Adult Liver Transplantation

Abstract

IntroductionInformation about the consequences of de novo donor-specific anti-human leukocyte antigen (DSA) antibody development in the long term after adult liver transplantation (LT) is scarce. We conducted a cross-sectional study in LT patients with a follow-up of at least 6 years. MethodsA total of 28 adult LT patients were included, with a median follow-up of 77 months (range, 63 to 96) and without preformed anti- human leukocyte antigen (HLA) antibodies prior to LT. The anti-HLA identification was performed with LABScreen Single Antigen, whereas the ability to fix the complement was demonstrated with C1q test (One Lambda). In both assays, a value >3.500 mean fluorescence intensity (MFI) was considered positive. The anti-HLA antibody specificities were compared with donor HLA antigens to confirm them as DSA. Hepatic fibrosis was assessed by transient elastography. ResultsIn 5 patients (17.8%), de novo DSA were detected, all them against DQ locus. In all of these cases (100%) the complement fixation was confirmed by C1q binding. The grade of hepatic fibrosis in de novo DSA patients was significantly higher compared with No-DSA patients (13.2 ± 9.2 KPa vs 7.3 ± 3.7 KPa; P = .02). It is noteworthy that in both groups of patients the levels of liver function tests (LFT) at the time of the study were normal or near the normal range with no difference between patients with or without de novo DSA. ConclusionsOur preliminary results are consistent with those previously demonstrated in pediatric LT, where de novo DSA production and humoral response could contribute to the liver fibrosis observed in the long term after LT in pediatric patients with normal or near-normal LFT.