Myeloid-derived suppressor cell, arginase-1, IL-17 and cl-CD95L: an explosive cocktail in lupus?

Myeloid-derived suppressor cells (MDSCs) (CD33+CD11b+) are a heterogenous population derived from immature myeloid cells consisting of two main subsets: CD15+CD66b+ granulocytic (G-MDSCs) and CD14+HLA-DR– monocytic (M-MDSCs) cells (1). G-MDSCs consist of relatively immature and pathologically activated neutrophils, whereas M-MDSCs are inflammatory monocytes (2). While MDSCs are associated with a poor clinical outcome in cancer, their role in chronic inflammatory diseases remains unclear probably because, among other explanations, the heterogeneity of this cellular population.