Effect of Syk inhibition over c-Cbl phosphorylation downstream of αIIbβ3. (A) To determine the role of Syk mediated phosphorylation downstream of αIIbβ3 platelets were incubated for 10 minutes with 2μM of Syk inhibitor OXSI-2 and then plated over fibrinogen coated plates for the indicated time points. Lysates were analyzed as on legend from Figure 1. (B) SFKs p-Y416 was also analyzed to confirm its intact activity under the same experimental conditions. (C) Densitometry analysis of 5 experiments. Bars represent mean ± SEM of the ratio of phosphorylated protein over total protein. Student t test performed (P < .05, no treatment vs OXSI-2 for residues Y700 and Y774; ns: non-significant for residue Y731).