Purpose of review: To describe most relevant data regarding strategies to achieve immunosuppression minimization and/or complete withdrawal in liver transplantation and to discuss the development of tolerance biomarkers to predict the success of immunosuppression weaning.
Recent findings: In clinical organ transplantation allograft tolerance has been attained through two different pathways: (1) tolerance or immunosuppression minimization has been attempted by administering induction therapies with or without infusion of donor hematopoietic cells; and (2) the availability of spontaneously tolerant liver and kidney recipients has been exploited to develop biomarkers of allograft tolerance. The use of transcriptional profiling is the most promising approach. Recent publications have identified a gene expression signature in tolerant patients.
Summary: Current immunosuppressive regimens reduce acute rejection episodes but promote a number of complications that have a negative impact on patient morbidity, mortality and quality of life. In this setting, achievement of tolerance is a major goal. Although there are no reliable markers to identify tolerant patients, recent studies have found that tolerant liver recipients exhibit unique peripheral blood transcriptional patterns. The difference in expression patterns is related to the immune response and could constitute the basis of a future diagnostic test of tolerance.