Figure 8. CD40 agonist exhibits partial antitumor activity and primes tumor-specific CD8⁺ T cells via monocytes/macrophages in Batf3^–/– mice.

(A) Experimental schematic. EP, endpoint. (B) Orthotopic tumor weights on day 14. (C) Proportion of splenic (left) and intratumoral (right) CD8⁺ T cells that bind CB_101-109:H-2D^b tetramer. There were no significant differences in tumor size between control and cDC1-depleted cohorts. (D) Tumor weights in treated or control Batf3^–/– mice on day 14. (E) Representative of tetramer⁺ T cell frequency gated on CD8 T cells. (F) Quantification of E. (G) Frequency of tetramer⁺ T cells from orthotopic CB^– or CB⁺ tumors on day 14 posttumor. Representative of n = 10 mice. (H) Frequency of CD8⁺tetramer⁺ T cells from Batf3^–/– mice treated with CD40 agonist and various cell depletions. CD8⁺tetramer⁺ T cell frequency in spleen (I) and tumor (J). (K) Frequency (left) and number (right) of the indicated CD11b⁺ myeloid subsets in Batf3^–/– mice that received control liposomes (-) or clodronate liposomes (+) and were treated with CD40 agonist in spleen (top) and tumor (bottom). (L) Myeloid subsets are gated on live, CD45⁺CD11b⁺ cells. (M) Representative histograms of EGFP among myeloid subsets from Batf3^+/+ and Batf3^–/– mice on day 7 after agonistic αCD40. (N) Graphed data from M in spleen (Spl) and tumor (Tum). All graphed data are mean ± SEM and each dot is an independent animal. Representative of at least 2 independent experiments. *P < 0.05, **P < 0.005, and ***P < 0.0005. One-way ANOVA with a Tukey’s posttest (B, C, D, I, J, and N); Student’s t test (F and K). n = 3–8 mice per group.