Effect of PTPεC on IFN-γ–induced STAT activation.

(A) M1 stable clones were treated with IFN-γ at 25 ng/mL for the times indicated and lysed. STAT1 activation was analyzed as in Figure3, and (B) STAT3 activation was analyzed as in Figure 2B. Cells were treated with IFN-γ for the times indicated. Total RNA was analyzed for IRF-1 and SOCS-1 mRNA by Northern blotting. (C) The expression levels of β-actin were also estimated.