GZMB and neoplasm: The latter recently proposed to identify those T cells specific for tumor-derived epitopes among melanoma, colon, ovarian, and lung TILs15,16, was mostly confined to CD127− Trm cells, which also expressed significantly higher levels of HLA-DR, GZMB, and the checkpoint molecules PD-1 and, at a lesser extent, TIGIT, and stained more frequently for the production of CD107a compared to CD127+ CD39lo Trm cells upon nonspecific stimulation ex vivo.