Myeloid-Derived Suppressor Cells (MDSCs) in Aged Mice: Focus on Inflammation

Abstract

As people get older, the homeostatic functions of many systems in the body like the immune system decline, which contributes to increase susceptibility to disease. The bone marrow of healthy individuals continually generates myeloid cells, which differentiate into mature cells like granulocytes, macrophages, or dendritic cells. However, under inflammatory conditions, there is an increased frequency of immature myeloid cells that can suppress T cell responses in peripheral secondary lymph organs in both human and murine hosts. The heterogeneous population of cells known as myeloid-derived suppressor cells (MDSCs), consisting of myeloid progenitors and immature myeloid cells, share a biological function: immunosuppression. This chapter reviews novel findings in mice about the nature of MDSCs and, in this context, discusses current knowledge about these cells during the aging process. MDSCs may have an important role in the regulation of the immune response during aging. MDSC dysfunction in aged mice may compromise the innate and adaptive immune systems, and thus understanding their role during aging may be useful for potential future therapeutics.