CD8A and neoplasm: We have shown that two relevant immunosuppressive factors, IL-10 and TGF-β, in high concentrations can extensively block cytotoxicity, CD8+ and CD4+ T cell activation, cytokine secretion, proliferation and differentiation of naïve T cells into central and effector memory cells in vitro (see Figure 2) when activated through an αCD3 BiMAb in the presence of MCF-7 tumor cells.