Finally, we found that selective, partial inhibition of Itk using Soquelitinib reduced basal CD69 expression in CAR-Jurkat cells while maintaining their ability to activate in response to antigen. These data suggest that TCRζ determines the pY signalling profile and that Itk drives basal activation of CD19-CAR Jurkats, which may impact evaluation of new CAR designs in CAR-Jurkat screens.
Finally, we find that selective, partial inhibition of Itk using Soquelitinib reduces basal CD69 expression in Jurkat CAR T cells while maintaining their ability to activate in response to antigen. Our data suggest that the ζ-chain determines the pY signalling profile of CD19-CAR Jurkat T cells and that Itk may drive antigen-independent CD19-CAR activation.