Figure 1.

H. pylori-induced phosphorylation of STAT3 on Ser727 and Tyr705 in cultured AGS cells. (A) Western blot analysis of P-STAT3^Ser727, P-STAT3^Tyr705 and STAT3 in whole lysates. AGS cells were treated with 100 MOI H. pylori (ATCC43504) and harvested at indicated time points. The relative levels of P-STAT3^Ser727 and STAT3 from three independent experiments are presented as means ± S.D. (B) Western blot analysis of P-STAT3^Ser727, P-STAT3^Tyr705 and STAT3 in whole lysates. AGS cells were transfected with WT and mutant vectors prior to H. pylori infection. The conditions for transient transfection and other experimental details are described in “Materials and methods”.