TIGIT and acute myeloid leukemia: To further assess whether the co-expression of NKG2D and TIGIT on the surface of γδ T cells may correlate with the prognosis of AML, we classified γδ T cells into four distinct subsets: NKG2D−TIGIT+, NKG2D+TIGIT+, NKG2D+TIGIT−, and NKG2D−TIGIT− (Figures 3A, B, D; Supplementary Figure S2).