Tumours grown in DKO mice displayed a greater accumulation of PD1hiTOXhi Tex cells under DR when compared to WT animals on the same diet (Fig. 6h,i), with ketolysis-deficient (that is, DKO) CD8+ TILs maintaining high TOX levels even under DR feeding conditions that normally reduce TOX expression in WT CD8+ TILs (Fig. 6j). Here, CD8A is linked to neoplasm.