Similarly, FOXO1-ADA-expressing CAR T cells also expressed similar levels of the activation markers PD-1 and TIM3 relative to control CAR T cells, consistent with the notion that FOXO1-ADA expression did not prevent CAR T cells from acquiring an effector-like phenotype upon tumour antigen recognition (Extended Data Fig. 5c). The gene discussed is PDCD1; the disease is neoplasm.