p110δ regulates naive and effector/memory CD4⁺ T-cell activation. CD62L⁺ (naive) and CD62L⁻ (effector/memory) CD4⁺ T cells from WT and p110δ^D910A mice were stimulated by anti-CD3 in the presence of DMSO alone, LY, or IC. After 48 hours, proliferation (A,C,E) and IFN-γ production (B,D,F) were measured. The effects of IC on naive (A-B) or effector/memory (C-D) T cells were determined. Proliferation (E) and IFN-γ production (F) were measured in WT cells when cells were treated with DMSO alone, 10mM LY, or 1mM IC. Data are mean ± SEM of replicate readings and are representative of at least 2 independent experiments.