IgE- and IgE+Ag-induced mast cell migration can be divided into the early phase of Lyn/Syk-dependent release of soluble factors and the later PI3Kγ-dependent phase. (A) PI3Kγ^-/- BMMCs were defective in migration in responses to SPE-7 IgE, IgE+Ag, or adenosine. (B) FcϵRIα^-/- cells in upper wells were incubated with lower wells containing wild-type, lyn^-/-, or syk^-/- cells in the presence of SPE-7 or SCF. (C) Wild-type, lyn^-/-, or syk^-/- cells in upper wells were incubated with lower wells containing 206 IgE-sensitized wild-type cells in the presence of DNP-HSA or SCF. Mean values ± SD are shown from 2 (A) or 3 (B,C) independent experiments.