Figure 2.
Olaparib Enhances the Antigen-Induced CAR-T Cell Responses In Vitro
(A) Schematic diagram of cytotoxic activities of CAR-T cells combined with olaparib. Target cells were pre-treated with 0, 1 μM, or 5 μM olaparib for 24 h. Then the medium of the co-culture system was added with or without olaparib (1 μM or 5 μM) in E-plate at 37°C for 18 h. (B) In vitro cytotoxic activities of CAR-T cells on EGFRvIII-negative tumor cells. (C) The cytotoxicity analysis after incubation of EGFRvIII-positive tumor cells and CAR-T cells at the three E/T ratios in different olaparib treatment groups. (D) The levels of IFN-γ, IL-2, and granzyme B in the co-cultured supernatants were determined by ELISA. (E) The number of gated cells indicates the dividing cell population of CAR-T cells. EGFRvIII-positive tumor cells were pre-treated with or without various concentrations of olaparib for 24 h. 1 × 105 CellTrace-labeled CAR-T cells were incubated with 1 × 105 EGFRvIII-positive tumor cells at a 1:1 E/T ratio in the presence of various concentrations of olaparib for 24 h. (F and G) The representative flow cytometry plots showing the frequencies of Annexin V+ (F) CAR-T cells and (G) EGFRvIII-positive tumor cells. All data are presented as the mean ± SEM of triplicate experiments. ∗p < 0.05, ∗∗p < 0.01.