Gene expression in self-activating CAR-T cells with CD28 or 4-1BB costimulatory domains.

We observed self-activation of SKM-CAR-T cells which target novel mesothelioma antigen. CAR-T with CD28 costimulatory domain showed signs of exhaustion while those with 4-1BB costimulatory domain did not. Changes in the gene expression by substituting CD28 co-stimulatory domain to 4-1BB co-stimulatory domain was investigated. We performed RNA-seq analysis of SKM-CAR-T cells with CD28 or 4-1BB together with T cells without transducing CAR.