CD4 and neoplasm: A schematic gating strategy for immune cells in a 4NQO-induced OSCC mouse model is shown in Figure 4A. Compared with the control group, the proportion of MDSCs and M2 macrophages in the PFC@O2 treatment group was significantly reduced (Figure 4B,C), and the proportion of CD4+ and CD8+T cells with anti-tumor effects was significantly increased by flow cytometric quantification analysis (Figure 4D,E).