Specific activity of FOLR1-CAR T cells against KB cells and analysis of T cell-mediated cytotoxic factors.

<p>Mock or FOLR1-CAR T cells were co-cultured with KB cells at an E/T ratio of 10:1 for 4 h. (A) The levels of cytokines IFN-γ, TNF-α, GM-CSF, and granzyme B were measured by ELISA and (B) the cytotoxic effects were evaluated by luciferase assay. (C) To determine the factors that induced cell death, FOLR1-CAR T cells were co-cultured with KB cells in the presence of 100 μM of Z-AAD-CMK, 0.1 μg/ml of anti-FasL antibody, and anti-TNF-a antibody. Experiments were repeated at least three times with similar results. The data are represented as the mean cytokine concentrations ± SD (pg/ml) and rate of lysis ± SD (%) from triplicate cultures. Statistical analysis was performed using the two-sided unpaired t-test (***P<0.001).