Fig. 4: Blockade of B7-H3 enhanced systemic antitumor immunity to eradicate tumors in combination with a neoantigen cancer vaccine and local radiotherapy.

a Scheme and regimen of AAV vaccination, radiotherapy and anti-B7-H3 antibodies. A total of 3 × 10⁵ CT26 cells were subcutaneously inoculated into the right leg of BALB/c mice, and AAV (1 × 10⁸ vg) particles were intramuscularly injected on days 5, 12, 19 and 24. Local radiotherapy (5 Gy) of the right leg was conducted on days 11, 14 and 17. Anti-B7-H3 antibodies (100 μg/mouse) were administered intraperitoneally on days 7, 10, 13 and 16. The tumor volume was measured every 3 days (n = 5–6/group). *p < 0.05. One-way ANOVA. b The relative tumor volume was measured on day 30 (n = 6-7/group). *p < 0.05, **p < 0.01 and ***p < 0.001. One-way ANOVA. c Representative images of apoptotic cells (cleaved caspase-3), CD11c⁺ DCs and GzmB⁺ immune cells within the tumor microenvironment were evaluated via immunofluorescence microscopy. d The quantification of apoptotic cells (cleaved caspase-3⁺ cells) is shown (n = 3). *p < 0.05 and **p < 0.01. One-way ANOVA. e The quantification of CD11c⁺ DCs is shown (n = 3). *p < 0.05 and **p < 0.01. One-way ANOVA. f The quantification of GzmB⁺ immune cells is shown (n = 3). **p < 0.01 and ***p < 0.001. One-way ANOVA. g The mRNA levels of the cytotoxic T-cell marker GzmB in resected tumors are shown (n = 3). *p < 0.05 and **p < 0.01. One-way ANOVA. h The mRNA levels of Ifnα2 in resected tumors are shown (n = 3). *p < 0.05 and **p < 0.01. One-way ANOVA. i The mRNA levels of Ifnβ1 in resected tumors are shown (n = 3). *p < 0.05 and **p < 0.01. One-way ANOVA.