CD14+ cells within PBMCs were isolated using anti-CD14 magnetic microbeads and LS column separation (Miltenyi Biotech) per the manufacturer’s instructions. These cells were then cultured in complete RPMI media (10% FBS and 2 mM L-Glutamax) for 7 days in the presence of GM-CSF (20 ng/mL) and IL-6 (20 ng/mL). GM-CSF was added on days 1, 3, and 5, whereas IL-6 was added only on day 533 34 (link) (online supplemental figure 1). The cells were then harvested on day 7, and flow cytometry was performed to assess the phenotype (CD33+CD11b+HLA-DRlowCD14+CD15-).