BMMCs were pretreated with different doses of PI3K inhibitors, LY294002 and wortmannin, 30 minutes prior to IgE/DNP (A and C, black bar) and 0.25μM ionomycin (C, gray bar) activation. IL-33 expression was analyzed by real-time PCR. (B) BMMCs pretreated with 10μM LY294002 or 100nM Wortmannin were activated with IgE/DNP for 24 hours. IL-33 protein expression was detected by intracellular staining. Gray line, isotype control; black dot, unstimulated; gray fill, IgE/DNP stimulation; black line, LY294002 treatment; black dash, wortmannin treatment. n=3 from 2-3 individual experiments; *p<0.05, **p<0.01, ***p<0.001, n.s. = no significant difference.