Differential requirement for the PI3K and Ras/MAPK pathways in FcγR-induced IL-1β and IL-6 production. BMMs were treated with Me₂SO (DMSO) or 10 μM LY294002 or 2.5 μM UO126 for 30 minutes at 37°C prior to stimulation with heat-aggregated IgG. (A) The levels of IL-1β and (B) IL-6 in cell lysates and supernatants were measured by ELISA. The graphs represent the mean and SEM of 3 independent experiments. Data were analyzed by Student t test. *P ≤ .05. (C) Protein-matched lysates from unstimulated and stimulated cells (stimulated for 7 minutes) were analyzed by Western blotting with phospho-Erk antibody. The bottom panel is a reprobe of the same membrane with anti-Erk antibody. (D) Parallel samples were probed with anti-phospho Serine Akt antibody, and the membrane was reprobed with anti-Akt antibody (bottom panel).