KLRG1 and neoplasm: Multi-parametric immunofluorescence analyses indicated that CD8+ TIL from anti-PD-1-treated B16F10E-KO tumours was more enriched with terminally differentiated KLRG1+ effector T cells than those from isotype-treated B16F10E-KO and anti-PD-1-treated B16F10E (Fig. 5d).