Fig. 4.

Genomic TGFβ RII disruption in CAR T-cells specific for MSLN or CLDN6 enhances their in vitro effector functions. A Genomic editing of TGFβRII in TGFβRII KO CAR T-cells does not impact on CAR expression irrespective of the antigen specificity when compared to WT CAR T-cells. B TGFβ at any dose inhibits MSLN or CLDN6 4-1BBζ CAR T-cell proliferation in the presence of antigen presenting iDCs as APCs. Of importance, proliferation of TGFβRII KO CAR T-cells remain unimpaired and stable even at a very high dose of exogenous TGFβ. Proliferation in either WT or KO groups proved to be antigen specific. C In short-term classical cytotoxicity assays (luciferase based) against immunostimulatory iDCs, TGFβ does not impair cytotoxicity of WT CAR or TGFβRII KO CAR T-cells. P values were determined by two-way Anova using multiple comparison test. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001. In all experiments, mean ± SD of three technical replicates are given and experiments, involving T cells, are repeated for at least three donors