Figure 7. Immunohistochemistry showed that TPE-IQ-2O PDT combined with immunotherapy increased the infiltration of CD8+ T cells into tumors. (A) Microscopic observation of CD4+CD8+ T lymphocyte infiltration in the subcutaneous LLC or MC38 tumors in each group, scale bar: 150 μm. (B, C) The proportion of CD4+CD8+ T lymphocytes in the subcutaneous LLC or MC38 tumors in each group; *P < 0.05, **P < 0.01 and ***P < 0.001 vs. control group).