Helicobacter pylori inhibits the cleavage of TRAF1 via a CagA-dependent mechanism

Figure 4 CagA is the major factor involved in inhibiting the cleavage of tumor necrosis factor receptor-associated factor 1. A: AGS cells transfected with tumor necrosis factor receptor-associated factor 1 (TRAF1) were treated with the apoptosis inducer (0.3 μg/mL CHX and 80 ng/mL TNF-α), and co-cultured with Helicobacter pylori (H. pylori) strain NCTC11637 or its isogenic vacA-, cagE- or cagA-null mutants, and analyzed for the cleavage of TRAF1 at 6 h and 12 h by western blotting; B: AGS cells transfected with TRAF1 were treated with the apoptosis inducer, and co-cultured with H. pylori strain NCTC11637, or its isogenic vacA-, cagE- or cagA-null mutants at the indicated cell/bacteria ratios, and analyzed for the cleavage of TRAF1 by western blotting; C: The same as shown in (A), but analyzed for uncleaved and cleaved caspase-8 by western blotting; D: The same as shown in (B), but analyzed for uncleaved and cleaved caspase-8 by western blotting.