Rescue of IL-2–induced Akt activation in Syk-impaired cells by constitutively active PI 3-kinase.
(A) IL-2–starved NK92 cells, treated with 25 μM piceatannol or DMSO, were infected with recombinant vaccinia virus encoding P110*, the constitutively active catalytic subunit of PI 3-kinase, or CD56 irrelevant control gene and then were stimulated with IL-2 (100 U/mL) for 5 minutes at 37°C. Cells were analyzed for Akt activation by Western blot analysis with Ser473-specific antibodies. (B) Cells were treated similarly to those in panel A, and whole-cell lysates were analyzed by in vitro kinase assays for Akt activation with H2B as the substrate. The same membranes were stripped and reprobed with anti–pan-Akt. Results are representative of 1 of 4 independent experiments.
