Fig. 2

Characterization of the PD-L1 CCR in primary T cells. a CD19/HER2-z-expressing T cells received a suboptimal activation signal when exposed to a single antigen, but dual-targeted CAR-T cells achieved optimal activation when engaged with CD19/HER2 and PD-L1. b-c The levels of IL-2 and IFN-γ produced by untransduced, CD19-z or CD19-z-PD-L1–28-engineered T cells (b) and HER2-z or HER2-z-PD-L1–28-engineered T cells (c) were measured by ELISA after 24 h of coincubation at an E:T ratio of 1:1 (b) or 3:1 (c). The results are reported as the mean ± SEM for five healthy donors (b) or three healthy donors (c), ** P < 0.01, *** P < 0.001, **** P < 0.0001 with respect to co-culture with CD19⁺ K562 cells (b) or SKOV3 cells (c), analyzed using a paired Student’s t-test. d The levels of IL-2 and IFN-γ secreted by untransduced, CD19-z- or CD19-z-PD-L1–28-engineered CD4⁺ T cells were measured by ELISA after 24 h incubation at an E:T ratio of 1:1 (K562) or 3:1 (A549). The results are reported as the mean ± SEM for three healthy donors, * P < 0.05, ** P < 0.01 with respect to co-culture with CD19⁺ K562/A549 cells, analyzed using a paired Student’s t-test. e The levels of IL-2 and IFN-γ produced by untransduced, HER2-z or HER2-z-PD-L1–28-engineered CD4⁺ T cells were measured by ELISA after 24 h incubation at an E:T ratio of 3:1. The results are reported as the mean ± SEM for two healthy donors with technical triplicates, * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001 with respect to co-culture with A549/NCI-H292/SKOV3 cells, analyzed using Student’s t-test