Multicolor Flow Cytometric Analysis of MDSCs

Human whole blood samples were labeled with fluorescent dye‐conjugated monoclonal antibodies against CD11b‐FITC (clone: ICRF44, Thermo Fisher Scientific, USA), CD33‐PE (clone: D3HL60.251, Beckman Coulter, USA), HLA‐DR‐PC5 (clone: Immu‐357, Beckman Coulter, USA), and CD14‐PC7 (clone: RMO52, Beckman Coulter, USA). Samples were hemolyzed using a lysis buffer and suspended in IsoFlow (Beckman Coulter, USA). Flow cytometric analysis was performed with Cytomics FC500 (Beckman Coulter, USA), and the results were analyzed with Flowjo software (Tree Star, Inc., Ashland, OR). As previously reported, CD11b⁺CD33⁺HLA‐DR^low/‐CD14⁺ cells were gated and regarded as human MDSCs
²⁵ (link),
²⁷ (link) (Figure S1).