Figure 7.

Hinge truncated EGFR sdCAR-T cells show progressively diminished response to human lung cancer xenografts in vivo. NOD/SCID/IL2γ-chain-null (NSG) mice were injected subcutaneously with 2×10⁶ SKOV3 cells stably expressing mKate2. Mice (N=5 mice/group) were injected with 5×10⁶ total T cells (~1x10⁶ CAR-T cells) intravenously. (A) Tumor volume was assessed using caliper measurements and (B) time to defined humane endpoint (tumor volume 2000 mm³) was assessed. P values are derived from Mantel-Cox test of survival curves in comparison with untreated mice. Δ Note that the experiment was ended early due to non-experimental related animal facility shutdown, and thus the final tumor measurement of day 112 is shown in (C). (D) Fluorescence imaging was performed at varying timepoints after tumor cell injection. (E) Blood was also collected at selected timepoints after tumor challenge to quantify the proportion of human CD45+ cells that were GFP/CAR+. (F) Staining for human CCR7 and CD45RA was used to assess the differentiation status of CAR/GFP+ cells or total T cells for mice treated with mock-transduced CAR-T cells. See inset for gating strategy used to define effector, naïve/SCM, central memory, or effector memory-RA+ (EMRA) cells.