Fig. 7.

IFN-γ-induced phosphorylation of the EGFr and consequent downstream signaling is not affected by PTPN2 knockdown. T₈₄ cells transfected with either control siRNA or PTPN2 siRNA were treated with IFN-γ (1,000 U/ml, bilaterally) for 24 h. Whole cell lysates were immunoprecipitated with an anti-EGFr antibody, blotted for phosphotyrosine (A), stripped, and reblotted for EGFr (B) and p110 (C). A: representative Western blot and densitometric analysis represent EGFr tyrosine phosphorylation. Data are expressed as a percentage of the respective controls (n = 3). B: secondary densitometric analysis demonstrates the magnitude of induction of EGFr tyrosine phosphorylation from baseline level (analysis was performed as described in Fig. 1C) in percentage of untreated cells transfected with control siRNA. C: representative Western blot and densitometric analysis show EGFr protein level. Data are expressed as a percentage of the respective controls (n = 3). D: representative Western blot and densitometric analysis show p110 protein level. E: representative Western blots of 3 similar experiments demonstrate the phosphorylation of ERK1/2 and the expression of total ERK1/2 in response to IFN-γ. Significant difference vs. the respective control: *P < 0.05. #P < 0.05 vs. IFN-γ treatment of T₈₄ cells transfected with control siRNA.