Figure 4.

High infiltration of PD‐1⁺‐expressing CD8⁺ T cells may be blocking the full therapeutic potential of the POx‐Man nanovaccine combined with TAM modulation. A–D) Tumor‐infiltrating immune cell populations for CD3⁺ (A), CD4⁺ (B), CD8⁺ (C), and PD‐1‐expressing CD8⁺ (D). Divalent combination of siTGF‐β1‐loaded POx‐Man nanovaccine and TAM modulation triggers a systemic activation of the CD8⁺ T effector. E,F) Percentage of the activated systemic effector CD8⁺ (E) and CTL (F) T cells. Increased systemic secretion of Th1 cytokines (triad IFN‐γ, IL‐2, and TNF‐α)‐expressing CD8⁺ T cells, for siTGF‐β1‐loaded POx‐Man Nanovaccine + Pexidartinib, predicts an improved cytotoxic CD8⁺/Th1 T‐cell activity and correlates with restricted tumor growth. G–I) Secretion of IFN‐γ (G), IL‐2 (H), and TNF‐α (I) by CD8⁺ T cells after restimulation of splenocytes in culture with relevant peptides for 6 h. Tumors and spleens were recovered on day 19 following tumor inoculation. The quantification was performed by flow cytometry analysis. Data are presented as mean ± s.d., n = 5 animals. Statistical significance was calculated by one‐way ANOVA with Dunnett multiple comparisons post‐hoc test.