Using murine models of H. pylori infection in MUC1-deficient mice (Muc1−/−), epithelial expression of MUC1 was shown to inhibit the adhesion of H. pylori to the gastric mucosae, restricting colonization of the stomach (McAuley et al., 2007; McGuckin et al., 2007; Lindén et al., 2009) and MUC1 expressed by monocytes reduced the severity of H. pylori-induced gastritis (Ng et al., 2016). Here, MUC1 is linked to gastritis.