Induction of immunosuppression with polyclonal antithymocyte globulins: an overview

The induction of immunological tolerance to solid organ allograft is currently a subject of major investigation due to the morbidity and mortality related to immunosuppressive therapy. Immunosuppression induction by recipient treatment may allow to tailoring the timing and dosage of standard therapy not only reducing adverse reactions but also improving the graft outcome. Depletion of recipient T cells with polyclonal antithymocyte globulins is one of the methods nowadays investigated both in experimental and clinical procedures, demonstrating a better outcome of organ engraftment. Our intention is to give an overview of the literature about the mechanisms of action of polyclonal ATGs, the status of induction treatment in clinical and experimental transplantation as well as of the possible pathophysiological relationships with acquired tolerance, delayed graft failure and ischemia-reperfusion injury.