Furthermore, in a murine model of gastritis caused by Helicobacter pylori, deletion of Arg2 in C57BL/6 mice was found to be associated with enhanced M1 polarization, including increased NO production, and with improved control of H. pylori infection, indicating that ARG2 contributes to immune evasion of H. pylori by restricting M1 macrophage activation (102, 103). This evidence concerns the gene ARG2 and gastritis.