Tumour antigen-reactive TILs contained features of mouse TEX and were enriched for gene signatures associated with tissue residency (CD103, HOBIT), effector function (GZMB, IFNG), negative feedback (HAVCR2, ENDTP1 (CD39)), and transcriptional control of exhaustion (TOX, BLIMP1). The gene discussed is IFNG; the disease is neoplasm.