Myeloid-Derived Suppressor Cells in Aged Humans

Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells whose immunosuppressive activities contribute to cancer and other diseases. MDSCs appear to increase with age, and this presumably contributes to immunosuppression and the increased incidence of certain diseases. Why MDSCs increase with age is not entirely clear. Herein we present evidence that MDSC expansion is due in part to age-related changes in hematopoiesis, including the acquisition of mutations that favor myelopoiesis, which are compounded by changes in the aging microenvironment that favor the production of MDSCs.