Fig 1: Extraction, identification, and purification of myeloid-derived suppressor cell and cultivation of dendritic cell. (A) Cells were extracted from the bone marrow of BALB/c mice and stained by monoclonal antibodies. Under flow cytometry, the expressive rate of Gr-1+MDSC, CD11b+MDSC, CD11c+MDSC, CD80+MDSC, F4/80+MDSC, and MHC-II+MDSC were 70.4%, 3.5%, 4.8%, 1.2%, 0.3%, 2.1% respectively. (B) The expressive rate of Gr-1+CD11b+MDSC was 22.6%. (C) After MACS by CD11b magnetic bead, purification of Gr-1+CD11b+MDSC reached 84.6%. (D) Most non-antigen-loaded dendritic cells grew adherently, with different sizes, star or spindle shape, and stretching tubers, but some of the cells seemed to have adopted a half-adherent state with rough surface. The expressive rates of CD11c, CD86, and MHC-II on DCs were 10.9%, 3.8%, and 27.9%, respectively, by flow cytometry. (E) On the 7th day, DCs were stimulated and activated by tumor antigens. DCs in the half-adherent state increased obviously with radial spikes and bigger shape. The expressive rates of CD11c, CD86, and MHC-II were 74.8%, 50.3%, and 49.8%, respectively, by flow cytometry. IgG FITC, a homotypic control antibody, was used to set the gate strategy. Scale bar = 100 µmol/liter. MDSC, myeloid-derived suppressor cell; MACS, magnetic-activated cell sorting; DC, dendritic cell; CD, cluster of differentiation