Deficiency of miR-31 reduces HIF1α activity and glucose metabolism in allogeneic T cells after BMT. Splenocytes (CD45.2⁺) from WT or miR-31 KO B6 mice were injected together with WT T cell–depleted (TCD) BM (CD45.1⁺) into lethally irradiated BALB/c mice. (A-B) Frequencies of HIF1α⁺ cells in gated live donor H2K^b+CD45.2⁺ CD4 (A) or CD8 (B) T cells in recipient spleens and skin-draining LNs are shown on day 50 to 60 post-BMT. Data shown are from 1 representative of 2 individual experiments. (C-D) Frequency of surface Glut1⁺ cells (C) and uptake of 2NBDG (D) in gated donor H2K^b+CD45.2⁺ CD4 or CD8 T cells are shown in recipient spleens. (E-F) CD4⁺CD25⁻ WT or KO cells were stimulated with plate-bound anti-CD3 (4 μg/mL) and soluble anti-CD28 (2 μg/mL) in 3% O₂ conditions. 2NBDG uptake in gated live CD4 T cells is shown on day 3 (E). In the same experimental setting, these activated CD4 T cells were subjected to Seahorse assay, and extracellular acidification rate (ECAR) was measured under basal conditions and after injection of 3 pharmacologic compounds: glucose (10 mM), oligomycin (1 μM), and 2-DG (100 mM). The diagram of ECAR and glycolysis calculated as increased ECAR after glucose injection are shown (F). *P < .05, **P < .01, ****P < .0001.