Figure 3.

HDAd-Derived IL-12p70 and PD-L1-Blocking Antibody Increase the Anti-tumor Efficacy of Adoptively Transferred HER2.CAR T Cells In Vivo

FaDu or SCC-47 cells were transplanted into the right flanks of NSG mice. A total of 1 × 10⁸ vps of HDAdCyto and HDAdPDL1 (1:1) were injected intra-tumorally. A total of 1 × 10⁶ HER2.CAR T cells expressing firefly luciferase (ffLuc) were systemically administered 3 days post-injection of HDAds. (A) Tumor volumes were measured at different time points. Data are presented as means ± SD (n = 4). *p < 0.001. (B) Bioluminescence of HER2.CAR T cells was monitored at different time points. Data are presented as means ± SD (n = 4). (C) T cells at the tumor site were isolated 22 days post-infusion, and HER2.CAR levels on T cells were analyzed by flow cytometry. The experiments were repeated with similar results. (D) T cells from tumor sites treated with HDAd0, HDAdIL-7, HDAdIL-12, or HDAdIL-21 co-injected with HDAdPDL1 were isolated 22 days post-injection and purified by a CD3 MACS column. To achieve sufficient T cells for analysis, cells from each group were pooled before analysis. DNA and RNA were extracted from purified T cells, and HER2.CAR copy numbers at DNA and RNA levels in each sample were quantified. The experiments were repeated with similar results.