CD48 and Sepsis: In this study, we challenged Gfi1:GFP knock-in reporter mice by cecal ligation and puncture (CLP) surgery and found that the population of CD11b+Ly6GlowLy6Chigh cells in this sepsis model were heterogeneous and consisted of both monocytic and granulocytic MDSCs and that CD48 can distinguish monocytic and granulocytic MDSCs during infection.