Purpose of review: Early 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 findings: Mounting 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.
Summary: Although 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.