Signal transduction proteins of the FcγR pathway are activated in ex vivo peritoneal macrophages of SHIP^−/− mice. Freshly purified peritoneal macrophages were lysed without any treatment. Western blots were used to determine levels of tyrosine-phosphorylated Vav (pVav) and total Vav (A), serine-phosphorylated Akt (pAkt) and total Akt (B), and serine- and tyrosine-phosphorylated SAPK/JNK (pJNK) and total JNK (C). (D) The ratio of the signal of phosphoprotein to total of the SHIP-deficient sample to the WT sample. Data are representative of 3 independent experiments. (E) Freshly isolated peritoneal macrophages from SHIP^−/− mice were cultured with the PI3K inhibitor (LY294002) or the JNK inhibitor (SP60025) or dimethyl sulfoxide for 6 hours. Supernatants were collected, and IL-6 levels were determined by ELISA. Results from 3 separate experiments are mean ± SE of IL-6 in picograms per milliliter.