Long-term outcomes and clinical impact of anti-HLA donor-specific antibodies

Introduction: the presence of donor-specific antibodies (DSA) is thought to affect survival of the allograft and patient after liver transplantation (LT). However, their significance is not well understood. Patients and methods: a prospective study was performed of 32 adult patients who underwent LT in 2011 to analyze the existence of DSA, associated risk factors and medium-term impact. Immunological determinations were performed immediately before LT and at three, six, 12 months and five years after LT. Results: eight patients (24.2 %) presented pre-formed DSA. However, titers were negative in all patients five years after LT and there were no associated events. Eight out of 24 patients (33.3 %) developed de novo DSA. After five years, only two remained positive; both were class II with high mean fluorescence intensity (MFI) values at diagnosis (over 15,000). No association was found between the development of DSA and the risk of rejection, graft loss or death. However, an increase in liver stiffness values was observed in patients with persistent DSA, and focal sinusoidal deposition of C4d and moderate liver fibrosis were reported. Conclusion: the incidence of DSA is high after LT. In addition, the persistence of de novo DSA could be associated with silent liver fibrosis with a potential impact on graft outcomes. Keywords: Liver transplantation. Donor-specific antibodies. Antibody-mediated rejection.