Stimulation of the mucosal barrier by pathogens is another critical factor facilitating the proliferation and activation of ILC2.24 When infection occurs, the mucosal barrier releases “alarmin” proteins such as IL-25, IL-33, and TSLP, which can activate ILC2 and help to trigger the type-2 immunity process.25 In a previous study, we proved that H. pylori infection promoted ILC2 in the gastric mucosa or PBMC. The gene discussed is IL33; the disease is infection.