Regulators with potential: Substantiating myeloid-derived suppressor cells in human organ transplantation

摘要

Myeloid-derived suppressor cells (MDSC) are regulatory innate immune cells that suppress immunity by inhibiting effector T cell responses or promoting regulatory T cell (Treg) expansion (1). Although the phenotypes and suppressive functions of MDSC were established initially in murine tumor models and cancer patients, MDSC are gaining attention as potent modulators of T cell responses in other inflammatory conditions (1). MDSC share a common lineage with other myeloid cells and this interrelated derivation makes phenotypic distinction of MDSC from monocytes, macrophages, dendritic cells (DC), granulocytes and their precursors difficult. However, distinct phenotypes of monocytic (M-MDSC) and granulo-cytic (G-MDSC), the two major populations of MDSC in mice and humans, have been established.