CD28 and neoplasm: In this aspect, we performed a co-culture experiment where isolated CD11b+ cells from the spleen of an orthotopic tumor-bearing mouse were sorted for CD11b+Ly6G+Ly6Clow (granulocytic; g-MDSCs) and CD11b+Ly6G-Ly6C+ (monocytic; m-MDSCs) (Supplementary Figure 1C) and co-cultured with CD3/CD28 microbeads activated CD8+ T cells (from naïve mice spleen) in the ratio 1:3 (MDSC: T cell) and treated with Mit-A.