Human Myeloid-Derived Suppressor Cells in Solid Organ Transplantation

The balance between effector and regulatory immune cells needs a very exquisite balance in the context of solid organ transplantation to avoid the rejection of the organ while maintaining the more immune competence as possible. In the last two decades the role of regulatory immune cells has been extensively studied, mainly with regulatory T cells (Tregs), and in the last years another subset of regulatory cells, named myeloid derived suppressor cells (MDSC), has gained importance. These cells have different mechanisms of action and some of them are differentially regulated in a number of immune-mediated processes. Thus, MDSC, which play important roles in tolerance of experimental models of solid organ transplantation, have been proposed as biomarkers of the degree of immunosuppression and risk of rejection. Besides, they are also thought as therapeutic approach for the establishment of tolerance in human transplantation.