Figure 3.

Schematic overview of immunosuppressive components of the TME, the immunosuppression on T cells, and the current immunotherapeutic strategies to overcome immunosuppression. The inner circle (light orange) shows the tumor cells and immunosuppressive immune cell types in the TME. The middle circle (red) indicates the immunosuppressive molecules. The outer circle (light blue) indicates the mechanism of inhibition on tumor-fighting immune cells (CD4+ T cells, CD8+ T cells, and NK cells). For each of these major mechanisms, the cells and the soluble factors released by the respective cells are shown in six slices. In the grey area of each slice, the current immunotherapeutic strategies are listed.