Bhlhe40 Keeps Resident T Cells Too Fit to Quit (Immunity)

Factors regulating the differentiation of tissue-resident memory T (TRM) cells and tumor-infiltrating lymphocytes (TILs) are incompletely understood. In this issue of Immunity, Li et al. identify Bhlhe40 as a transcriptional regulator of CD8+ TRM cell and TIL persistence and activity by orchestrating metabolic and epigenetic programming.