ARID5B regulates metabolic programming in human adaptive NK cells

Natural killer (NK) cells with adaptive immunological properties expand and persist in response to human cytomegalovirus. Here, we explored the metabolic processes unique to these cells. Adaptive CD3−CD56 ^dim CD57 ⁺ NKG2C ⁺ NK cells exhibited metabolic hallmarks of lymphocyte memory, including increased oxidative mitochondrial respiration, mitochondrial membrane potential, and spare respiratory capacity. Mechanistically, we found that a short isoform of the chromatin-modifying transcriptional regulator, AT-rich interaction domain 5B (ARID5B), was selectively induced through DNA hypomethylation in adaptive NK cells. Knockdown and overexpression studies demonstrated that ARID5B played a direct role in promoting mitochondrial membrane potential, expression of genes encoding electron transport chain components, oxidative metabolism, survival, and IFN-γ production. Collectively, our data demonstrate that ARID5B is a key regulator of metabolism in human adaptive NK cells, which, if targeted, may be of therapeutic value.