Figure 7.

BiTE mediates anti-tumor activity in antigen positive cells in bivalent targeting constructs

(A) Vector maps of 806CAR-Hu08CAR, 806BiTE-Hu08CAR, Hu08BiTE-806CAR, and 806BiTE-Hu08BiTE constructs. (B) Flow cytometric detection of T cell transduction by mCherry expression. (C) Bivalent T cell activation, as measured by CD69 expression, in CD4⁺ (left) and CD8⁺ (right) T cells after 16 h co-culture with target cells. (D) Flow-based intracellular cytokine (IFNγ, IL2, and TNFα) staining of bivalent targeting T cells co-cultured with target cells. CD4⁺ (top) and CD8⁺ (bottom) subgroups of T cells were distinguished by human CD8 staining. (E) Bioluminescence cytotoxicity assays of bivalent targeting T cells co-cultured with 5077^EGFRvIII+ cells (left panel), 5077^IL13Rα2+ cells (middle panel) and D270 cells (right panel), analyzed at different effector/target (E:T) ratios (0.625:1, 1.25:1, 2.5:1, 5:1, 10:1, and 20:1) and compared with the UTD T cell group. Statistically significant differences were calculated by one-way ANOVA with post hoc Tukey test. ns, not significant; ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, ∗∗∗∗p < 0.0001. Data are presented as means ± standard deviation.