CD63 and Sepsis: In vitro stimulation of monocytes from healthy donors with Colony Stimulating Factors (CSFs), in particular GM-CSF and Lipopolysaccharides (LPS), induced IL-1R2<sup>+</sup> Mono/Mφ, which recapitulated the characteristics of sepsis-associated monocytic cells, including low expression of HLA-DR, high levels of macrophage markers such as MS4A4A and CD63, immune checkpoints, immunosuppressive molecules and selected scavenger receptors.