An NK-like CAR T cell transition in CAR T cell dysfunction.

Chimeric antigen receptor (CAR) T cell therapy has achieved remarkable success in hematological malignancies but remains ineffective in solid tumors, due in part to CAR T cell exhaustion in the solid tumor microenvironment. To study dysfunction of mesothelin-redirected CAR T cells in pancreatic cancer, we establish a robust model of continuous antigen exposure that recapitulates hallmark features of T cell exhaustion and discover, both in vitro and in CAR T cell patients, that CAR dysregulation is associated with a CD8+ T-to-NK-like T cell transition. Furthermore, we identify a gene signature defining CAR and TCR dysregulation and transcription factors, including SOX4 and ID3 as key regulators of CAR T cell exhaustion. Our findings shed light on the plasticity of human CAR T cells and demonstrate that genetic downmodulation of ID3 and SOX4 expression can improve the efficacy of CAR T cell therapy in solid tumors by preventing or delaying CAR T cell dysfunction. [Display omitted] • CAR T cells under chronic antigen stimulation show hallmarks of T cell exhaustion • CAR dysregulation is associated with a CD8+ T-to-NK-like T cell transition • CAR T cells with NK-like transition were identified in patients after treatment • Unlike WT CAR T cells, ID3 and SOX4 knockout CAR T cells retain anti-tumor immunity Continuous antigen exposure drives CAR T cell exhaustion and promotes CD8+ T-to-NK-like T cell transition. Transcription factors ID3 and SOX4 are upregulated during CAR dysfunction and regulate genes associated with exhaustion, including NK receptors. Knocking out ID3 and SOX4 in CAR T cells slows dysfunction and improves anti-tumor immunity. [ABSTRACT FROM AUTHOR]