Fig. 2: CD8+ T cells are not tumoricidal despite expressing granzyme B and IFNγ.

a Schematic representation of chemotherapy treatment cycles. b Flow cytometry gating strategy for T cells from dissociated G69-tumor tissues. c–e Quantification of CD3+ T cells and their subpopulations of CD4+ and CD8+ T cells from dissociated G69-tumor tissues treated with vehicle (n = 12 biologically independent samples) or GC (n = 11 biologically independent samples) for two cycles. Data are presented as mean values ± SEM. (Two-tailed, unpaired t-test; p = 0.048, p = 0.023, and p = 0.018 respectively). f, g Immunofluorescence analysis of CD3+ T-cell infiltration in vehicle and GC-treated G69 tumors. Selected ROIs (g, 1–4) are representative areas that depict CD3+ T-cell localization in the tumor periphery and decreased CD3+ T-cell infiltration in the tumor (Scale bar: 100 μm; Images representative of n = 3 independent experiments). h, i Flow cytometry plots and quantification of IFNγ expression in CD8+ T cells from vehicle (n = 4 biologically independent samples) and GC-treated (n = 3 biologically independent samples) G69-tumor tissues. Data are presented as mean values ± SEM. (*—Two-tailed, unpaired t-test; p = 0.024). j, k Flow cytometry plots and quantification of GZMb expression in CD8+ T cells from vehicle (n = 4 biologically independent samples) and GC-treated (n = 3 biologically independent samples) G69-tumor tissues. Data are presented as mean values ± SEM. (***—Two-tailed, unpaired t-test; p = 0.0005). l Flow cytometry plots of CD8+ T-cell infiltration in IgG or CD8-depleted G69-tumor tissues. m Endpoint G69-tumor volume from mice treated with IgG or anti-CD8a specific antibody (200 mg/mouse) every other day for 2 cycles of GC (n = 4 biologically independent samples, respectively). Data are presented as mean values ± SEM. Source data are provided as a Source data file. ns not significant.