Fig. 4
Effects of ADVNE and ADVPPE on Macrophage M1 Polarization and TEM/TE Infiltration. (A) C57BL/6 mice were subcutaneously inoculated with 1 × 10⁶ MC38 cells. When the tumors reached a volume of 50–100 mm³, intratumoral injections of 3 × 10⁸ PFU of ADV were administered every other day for a total of three treatments. On day 7 after the first virus treatment, flow cytometry was used to assess the proportions of M1 and M2 macrophages and the infiltration of TEM/TE in the tumor microenvironment (n = 6 mice per group). (B) Infiltration of TAMs, NK cells, DCs, CD4+ T cells, and CD8+ T cells in the tumor microenvironment of mice following different virus treatments (n = 6 mice per group). (C) Schematic of the immune cell depletion experiment. C57BL/6 mice were subcutaneously inoculated with 1 × 10⁶ MC38 cells. Starting the next day, the mice received intraperitoneal injections of 500 µg of anti-CD8α or anti-CSF1R every other day to deplete CD8+ T cells or macrophages, respectively. When the tumors reached 50–100 mm³, intratumoral injections of 3 × 10⁸ PFU of adenovirus were administered every other day for a total of three treatments. On day 7 after the first virus treatment, flow cytometry was used to evaluate immune cell infiltration into the tumor microenvironment. (D) Efficiency of macrophage and CD8+ T-cell depletion in the tumor tissues of MC38 tumor-bearing mice one week after treatment with anti-CD8α and anti-CSF1R antibodies, as assessed by flow cytometry. (E) Subcutaneous tumor volume and survival of mice in different treatment groups after CD8+ T-cell depletion (n = 8 mice per group). (F) Subcutaneous tumor volume and survival of mice in different treatment groups after macrophage depletion (n = 8 mice per group). (G) Infiltration of M1-like and M2-like macrophages in the tumor microenvironment after CD8+ T-cell depletion (n = 6 mice per group). (H) Infiltration of CD8+ cells and TEM/TE cells in the tumor microenvironment after macrophage depletion (n = 6 mice per group). The data are presented as the means ± SDs. NS, no significant difference; ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, ∗∗∗∗p < 0.0001