Although both expression of CD127 and increased IL-2 production upon ex vivo stimulation may suggest early differentiation among Trm cells, the two subsets did not differ in the expression of TCF7, a master transcription factor regulating the persistence and the stem-like potential of peripheral and tumor-infiltrating precursors of exhausted CD8+ T cells (Tpex)37, thereby suggesting a poor overlap between CD127+ CD39lo Trm and Tpex. The gene discussed is CD8A; the disease is neoplasm.