FIGURE 6.

CD151 deficiency leads to enhanced and sustained ERK1/2 and Akt activation in IgE-stimulated mast cells. BMMCs from WT and CD151^−/− mice were sensitized with 1 μg/ml IgE for 24 h and then stimulated with 0.5 μg/ml DNP-HSA for the time points indicated. Cell lysates were subjected to immunoblotting analysis of the following phosphorylation events: Syk phosphorylation at Tyr^519/520 and Tyr³¹⁷, PLCγ1 at Tyr⁷⁸³, Akt phosphorylation at Ser⁴⁷³, ERK1/2 phosphorylation at Thr²⁰²/Tyr²⁰⁴, and total phosphotyrosine detection, which represents total phosphorylation events following IgE stimulation. Representative Western blots are shown on the left, as phosphorylation bands followed by total protein loading controls. Bar graphs on the right show intensities of Western blot bands quantified by densitometry analysis. Fold increase in phosphorylation intensity was measured relative to total levels of detected proteins of interest. Densitometry values are mean ± SEM of three independent Western blots. Filled columns indicate WT; open columns indicate CD151^−/−. *p < 0.05.