Akt is required for maximal IL-7–stimulated glucose uptake. (A-C) T cells were purified from control, Akt1-, and Akt2-deficient mice and analyzed for (A) Akt isoform expression, (B) Glut1 protein levels by immunoblot, and (C) glucose uptake. (D,E) Purified T cells from wild-type, Akt1-, and Akt2-deficient mice were stimulated with anti-CD3 and anti-CD28 with IL-2 for 2 days, cultured in IL-2 alone for 1 day, then washed and neglected or cultured in IL-7 for an additional day. (D) Glut1 protein levels were determined by immunoblot and (E) IL-7–stimulated glucose uptake (treated − untreated, the difference in uptake + IL-7 above uptake in untreated cells) was measured. (F) IL-7Rα–expressing FL5.12 cells that expressed Bcl-xL to maintain cell viability were washed and cultured without cytokine or with IL-7 in DMSO (vehicle) or LY294002. Glucose uptakes were measured after 14 hours and IL-7–stimulated glucose uptakes are shown. (G) FLAG-Glut1 was transfected into IL-7Rα–expressing FL5.12 cells that expressed Bcl-xL to maintain cell viability. One day after transfection, cells were washed and cultured without cytokine or with IL-7 in DMSO (vehicle) or LY294002 for an additional 14 hours and surface FLAG-Glut1 was determined. Values represent averages from 5 (C) and 4 (E) independent experiments. IL-7–stimulated glucose uptake and FLAG-Glut1 levels were determined using triplicate unstimulated and stimulated samples. Values represent means plus or minus SEM of multiple experiments (C,E) or triplicate samples within the given experiment (F,G). By Student t test, *P < .05, **P < .005. White vertical lines have been inserted to indicate repositioned gel lanes in panels A and D.