FIGURE 4.

The combination of fractionated radiotherapy with anti‐PD‐1 enhances the T cell infiltration of MC38 tumor‐bearing mice in draining lymph nodes and spleen. Responses in draining lymph nodes and spleens were tested 48 h after treatment: (A–C) Mean CD3⁺CD8⁺ T cells, CD3⁺CD4⁺ T cells, and CD11b⁺Gr1⁺ myeloid‐derived suppressor cells (MDSCs) as fraction of CD45⁺ splenocytes and (D–F) CD45⁺ T cells in draining lymph nodes of the primary and second tumors; (G) Highly intra‐tumor and inter‐tumor heterogeneous PD‐L1 expressions were shown in the tumor tissues. *p < 0.05 compared with control group.