Donor-specific human leukocyte antigen antibodies in intestinal transplantation

Purpose of reviewEarly outcomes following intestinal transplantation (ITx) have markedly improved in recent years. However, there has been a lack of improvement in long-term outcomes. Increasing amounts of data suggest the humoral immune system is a major contributor to rejection and late allograft loss. This review will summarize the available data on donor-specific human leukocyte antigen antibodies (DSAs) in ITx, with a focus on the clinical significance of DSAs, diagnosis of antibody-mediated rejection (AMR), and available treatment modalities. Areas requiring further investigation will also be identified.Recent findingsMounting evidence shows that pre- and/or posttransplant DSAs are associated with rejection and allograft loss following ITx. Preformed DSAs are present in nearly one-third of ITx recipients, and de-novo DSAs develop in up to 40% of patients. Diagnosis and treatment of AMR remains challenging, but reports indicate that when optimal induction and maintenance immunosuppressive agents are used, the impact of DSAs may be negligible.SummaryAlthough data are limited due to center differences with regard to patient population, induction and maintenance immunosuppression protocols, and monitoring strategies, DSAs are associated with poor outcomes following ITx. A consensus to define AMR and optimal treatment strategies is needed.