PDCD1 and neoplasm: Until now, CRISPR/Cas9 editing had been successfully used to disrupt PDCD1 gene in CAR-T cells targeting either CD19,20 mesothelin22 or HCC.21 However, although the feasibility of PDCD1 editing had been shown in human primary CTL,24 25 the feasibility to disrupt PDCD1 gene in CD8+ effector/memory T cells specific for tumor antigens was still lacking.