Bcr-Abl kinase activity is diminished in Bcr-Abl–transduced SHP-2^Δ/Δ cells. WT/Bcr-Abl–, SHP-2^Δ/Δ/Bcr-Abl–, and the vector control–transduced cells were expanded in IL-3–containing medium for 5 days. (A) Whole-cell lysates were prepared and then immunoprecipitated with anti–c-Abl Ab followed by the kinase assay as described in “Materials and methods.” Lysates of Bcr-Abl–transduced WT cells were immunoprecipitated with rabbit IgG as the negative control. (B) Bcr-Abl–transduced WT and SHP-2^Δ/Δ cells were cultured in IL-3–free medium for 24 hours. Whole-cell lysates were prepared and examined with anti-pY immunoblotting (IB). Activities of Akt and Erk kinases were also analyzed with IB using anti–phospho-Akt and anti–phospho-Erk Abs. Shown are representative results from 3 independent experiments.