<i>cagY</i> variants that fail to induce IL-8 and translocate CagA do not induce expression of NF-κB.

<p>(A) Co-culture of <i>H. pylori</i> with AGS cells stably transformed with a reporter plasmid demonstrated that activation of NF-κB was seen in WT J166 but not in a strain with a deletion of the <i>cag</i>PAI (▵PAI). Reintroduction of J166 <i>cagY</i> into a <i>cagY</i> deletion mutant restored NF-κB activation. <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1003189#s1" target="_blank">Introduction</a> of <i>cagY</i> from monkey (B) or mouse (C) output strains showed that increased NF-κB activation compared to ▵<i>cagY</i> (▵Y) or ▵PAI was seen only in strains bearing a <i>cagY</i> allele that was competent for induction of IL-8 and translocation of CagA (rOut3, mOut3, mOut4). ***<i>P</i><0.001.