Fig. 2: Induction of protective immunity by the primary tumor mediates metastatic dormancy.
From: CD39+PD-1+CD8+ T cells mediate metastatic dormancy in breast cancer
a Experimental design. 4T1 or 4T07 cells (3 × 105) were injected i.v. into female BALB/c mice. Analysis 25 d later. b Number of lung metastatic nodules. 4T1, n = 5; 4T07, n = 4. c Experimental design. 4T1 or 4T07 cells (105) were injected into the mammary fat pad of female BALB/c or BALB/c Foxn1nu/nu mice. Analysis 30 d later. Lungs of “WT Late” mice were analyzed when the 4T07 tumor size reached the size of the BALB/c Foxn1nu/nu group (d 35). d Weight of primary tumors. Left panel with closed symbols, 4T1. Both groups n = 5. Right panel with open symbols, 4T07. Foxn1nu/nu, n = 7; WT, n = 5; WT late, n = 4, **p = 0.006 (Foxn1nu/nu vs. WT), **p = 0.0027 (Foxn1nu/nu vs WT Late). e Number of lung metastatic nodules. Left panel with closed symbols, 4T1; right panel with open symbols, 4T07, **p = 0.071 for both comparisons. f Experimental design. Female BALB/c mice received 0.5 mg anti-CD8 or isotype control i.p. at days −1 and +5 relative to injection of 105 4T07-mCh cells in the mammary fat pad. Analysis 25 d later. g Lung metastatic load measured by bioluminescence, ****p < 0.0001. Anti-CD8, n = 9; isotype n = 10. h Bioluminescence images. Anti-CD8, n = 9; isotype n = 10. i Experimental design. 4T07 cells (105) or PBS were injected into the mammary fat pad of female BALB/c mice on d 0. On d 11, 3 × 105 4T07-LZ cells were injected i.v.; analysis of lung metastatic load on d 25. j Quantification of lung metastatic load by bioluminescence. 4T1, n = 5; 4T07, n = 4, ***p = 0.0021. k Bioluminescence images. l 4T07 cells (105) or PBS were injected into the mammary fat pad of female BALB/c mice on d 0. On day 8, mice were injected i.p. with 500 µg anti-CD8 or isotype control. On d 15, 3 × 105 4T07-LZ cells were i.v. injected and lung metastatic load was quantified on d 25. m Quantification of the lung metastatic load by bioluminescence on d 25. All groups n = 5, ****p < 0.0001. Each symbol represents an individual mouse. ns = not significant. 2-tailed Student’s t-test with Welch’s correction (b, d left panel, e left panel, g, j); 2-sided ANOVA with Bonferroni correction (d right panel, e right panel, m). The bar represents the mean ± SD. Results are representative of 3 (f, g, h) or 2 (all other) independent experiments.
