Figure 2.

Rapamycin and DON inhibited the BM cell differentiation into DCs and macrophages and promoted G-MDSC expansion in vitro. (A,B) BM cells were stimulated with GM-CSF and cultured with the drug regimens described for lymphocyte culture in Fig. 1A. The cells were collected on day 5 and stained with anti-CD11b, anti-Gr1, anti-CD11c, and anti-F4/80 antibodies. The frequencies of DCs (CD11c⁺ CD11b⁺), macrophages (F4/80⁺ CD11b⁺), and MDSCs (Gr1⁺ CD11b⁺) were analyzed by flow cytometry. Data are representative of 4 independent experiments. (C,D) BM cells were collected on day 5 of culture and stained with anti-CD11b, anti-Ly6G, and anti-Ly6C antibodies. The frequency of M-MDSCs (CD11b⁺ Ly6G⁻ Ly6C^high) and G-MDSCs (CD11b⁺ Ly6G⁺ Ly6C^int) was analyzed by flow cytometry. Data are representative of 5 independent experiments. Bars show mean ± SEM. ^*P < 0.05; ^**P < 0.01; ^***P < 0.001. Rapa, rapamycin.