Fig. 6 |. Co-stimulatory signaling is required for PD-L1xCD3 mediated anti-tumor effects.

a, C57BL/6J mice were inoculated with 1×10⁶ MC38 tumor cells and treated with PD-L1xCD3 (0.25 mg/kg on day 10 and 15), 200 μg anti-B7–1 and anti-B7–2 were administrated on day 10, 13 and 15. Experimental design (a, left), tumor growth curve (a, middle) and IFNγ-producing antigen specific CD8 T cells (a, right) were shown. b-e, CD8 T cells were co-cultured with either tumor cells or dendritic cells in the presence of bispecific antibodies. T cell activation (b), supernatant IFNγ (c), apoptotic T cells (d) and supernatant IL-2 (e) were measured by flow cytometry and CBA. f-g, Cumulative survival in colorectal adenocarcinoma (f) and liver hepatocellular carcinoma (g) patients according to CD8 infiltration and CD28 level in TCGA database (top 10% vs bottom 10%). Representative result from two independent experiments were shown as mean ± SEM (n=5 biological replicates). Statistical analysis was performed by one-way ANOVA (a, right and b-e), two-way ANOVA (a, middle) with Tukey’s multiple comparisons test and Log-rank test (f-g). ****P ≤ 0.0001.