178 CCR2 Is Essential for H. pylori Induced Immune Tolerance in Mice

mutant (N=16) and sacrificed eight weeks post-infection. Colonization density was similar between groups. Consistent with the in vitro analysis, infection with wild-type H. pylori strain 7.13 resulted in a significant and cagA-dependent decrease in hepcidin expression within gastric antral epithelial cells (82% reduction wild-type 7.13-infected vs. uninfected animals, P<0.05; 88% reduction wild-type 7.13 vs. cagAmutant, P<0.001), as assessed by immunohistochemistry. Collectively, these data demonstrate that H. pylori downregulates hepcidin in a cag-dependent manner in vitro and in vivo, which likely disrupts host iron homeostasis and facilitates iron acquisition.