A. Purified human blood eosinophils were primed with control buffer, IL-5 or IL-3 for 1 hr, followed by stimulation with fMLP or control for the indicated time points. Cell lysates were processed by SDS-PAGE and immunoblotted for pERK1/2 and actin (A, N=3) as detailed under Materials and Methods. B and C. Eosinophils were primed with control buffer or IL-5 for 1 hr followed by a two-min stimulation with fMLP or CCL5. Cell lysates were subjected to SDS-PAGE and immunoblotted for pERK1/2 (B, N=5), pAkt (C, N=4) and Grb2.