Fig. 5

CD4⁺ T cells are critical for the efficacy of the combination therapy. a Specific immune cell subsets (CD4⁺ T cells, CD8⁺ T cells, or CD11b⁺ cells) were depleted to explore their relative contribution to the observed efficacy. Kaplan-Meier curves are shown for all groups described compared to isotype control. The number of mice per group (n) and median survival (ms) are listed. All experiments were performed twice with n = 5 biological replicates. Dosing schedule is shown at the top of the figure. Statistics were calculated using the Log-rank (Mantel-Cox) test. ** p ≤ 0.01, **** p ≤ 0.0001. b-f Peritoneal cell suspensions from tumor-bearing mice treated with vehicle (Veh); chemotherapy (Chemo); anti-IL-10, 2′3’-cGAMP, and anti-PD-L1 immunotherapy (IT); or both Chemo and IT (Combo) were assessed by flow cytometry 13 days after initiation of treatment. (b) Bar graphs show quantification of flow cytometry gating of CD4⁺ and CD8⁺ T cells. (c) Increased numbers of RORγt- and FoxP3-expressing CD4⁺ T cells are observed with Combo therapy. (d) CD4⁺ T cells expressing activation markers are observed. (e) Increased numbers of dendritic cells are observed upon Combo treatment even at this late timepoint. (f) Flow cytometry gating of subsets of GZMB expressing CD4⁺ T cells are shown as scatter plots and quantified at right. MHCII-expression on cancer cells is confirmed. The experiment was performed twice with n = 4 biological replicates. Statistics were calculated using one-way ANOVA with Tukey’s multiple comparisons test. Data are presented as mean ± SEM * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, **** p ≤ 0.0001