Fig. 6. mtDSN-2 synergizes with immunotherapies against solid tumors.

a Growth kinetics of 4T1 tumors after different treatments (n = 6 mice/group). b Kaplan–Meier survival of 4T1 tumor-bearing BALB/c mice (n = 6 mice/group). c Immunofluorescence staining of the tumor sections showed CD8⁺ T-cell infiltration. n = 3 mice/group. d H&E staining images of lung tissue sections. Red arrows indicate metastatic foci. The representative images are shown from six independent samples. e Quantification of the metastatic foci in lung tissues (n = 6 mice/group). Mice were sacrificed and lungs were excised for analysis when tumor volume exceeded 1500 mm³ or at the endpoint of the experiment. Individual MC38 tumor growth curves (f) and average tumor growth profiles (g) in each group (n = 9 mice/group). h, Kaplan–Meier survival of MC38 tumor-bearing C57BL/6 mice (n = 9 mice/group). P indicates the statistical significance relative to the saline-treated group. Immunofluorescence staining of the tumors indicated CD8⁺ T-cell infiltration (i) and the corresponding quantification (j), a.u., arbitrary units. Data of eight different views from 3 biologically independent samples. k Tumor growth curves after tumor rechallenge (n = 8 for healthy control, n = 3 for mtDSN-2, and n = 8 for mtDSN-2 + anti-PD-1 cured mice). Flow cytometry plots and percentages of T_EM (CD44⁺CD62L⁻) or T_CM (CD44⁺CD62L⁺) cells in PBMCs (l) and spleens (m, n) from immunized mice on day 33 (n = 8 mice/group). The data are presented as the mean ± s.d. NS: not significant. Statistical analysis by two-way ANOVA with Turkey’s multiple comparisons test (a, g), log-rank test (b, h), one-way ANOVA with Turkey’s multiple comparisons test (e, j), or Student’s t test (l–n). Source data are provided as a Source data file.