Compared with intestinal TCRαβ+CD8αβ+ IELs and TCRγδ+CD8αα+ IELs, TCRαβ+CD8αα+ IELs harbor a unique expression pattern of members of the Ly49 family of NK cell receptors, which are essential for cancer immunosurveillance mediated by NK cells [18, 45]. This evidence concerns the gene KLRD1 and cancer.