CSF2 and neoplasm: Surprisingly, when co-cultured with tumor cells, the level of cytokine released by δ-TCRγδ-T and γ-TCRγδ-T cells, such as IFNγ and GM-CSF, was lower than those by CAR-T cells (Fig. 2E), except that in SK-MEL-5 cells, which could account for the ineffective killing of SK-MEL-5 by CAR-T cells (Fig. 2C).