Myeloid-derived suppressor cells:mechanisms of immune suppression and advancements in anti-tumor immunity therapy

Myeloid-derived suppressor cells(MDSCs) are a heterogeneous population of cells derived from myeloid progenitor cells and immature myeloid cells.MDSCs increase in large number under the conditions of cancer,inflammation,and infection.MDSCs are able to suppress the immunity and promote tumor-cell invasion and metastasis through multiple mechanisms.In this review,we briefly summarized the biological features of MDSCs,the mechanisms of immune suppression,and the strategies of anti-tumor therapy to target MDSCs.