Zymosan but not S.aureus induced tyrosine phosphorylation of PLC γ2. (A) Macrophages were stimulated with zymosan(z) or S.aureus (S.a) for 45 min. (B and C) Macrophages were pretreated for 15 min with either PP2 (5 μM), wortmannin (W, 100 nM) (B) or SKI-1 (5 μM) (C) followed by stimulation with zymosan for 30 min. Cell lysates were immunoprecipitated with antibody against PLCγ2 as described, followed by Western blot analysis with phosphotyrosine-specific antibody. The membrane was stripped and reprobed with antibody against PLCγ2. The data are representative of three separate experiments.