The analysis of PI3K signaling in T cells from APDS patients showed a constitutive hyperphosphorylation of both AKT (on Thr308: PI3K/PDK1 dependent and on Ser473: mTORC2 dependent) and S6 (on Ser235/236 and Ser240/244: mTORC1 dependent) (50–52, 64, 65, 67). The gene discussed is PIK3CB; the disease is activated PI3K-delta syndrome.