Figure 1.

PSMA-Targeting CARs

(A) Schematic of CAR-expressing γ-retroviral vectors. See Figure S1A for details. (B) Evaluation of CAR expression. Activated T cells were transduced with γ-retroviral vector and stained with anti-human IgG antibody (CAR) and CD3. (C) Cytolytic activity. CAR T cells were co-cultured at the indicated E:T ratios with C4-2 cells (PSMA⁺/PD-L1⁻). Cytotoxicity was determined using a cell viability assay (n = 6). (D) Cytokine release. CAR T cells were co-cultured with PSMA⁺ C4-2 or PSMA⁻ Du145 cells, respectively, and the concentration of IFN-γ was determined in the supernatant (n = 3). (E) PSMA-mediated activation of CAR T cells. Activation of CAR T cells that were co-cultured with PSMA⁺ C4-2 tumor cells was assessed by evaluating CD25 expression (n = 3). ∗p < 0.05, ∗∗p < 0.01, ∗∗∗∗p < 0.0001. UT, untransduced cells; PSMA, prostate-specific membrane antigen; PD-L1, programmed cell death ligand 1; MFI, mean fluorescent intensity.