A role for IL-22 in the relationship between intestinal helminths, gut microbiota and mucosal immunity

► IL-22 helps maintain barrier homeostasis against intestinal pathogens and commensal bacteria. ► The role of IL-22 in helminth infections and in response to commensal and pathogenic bacteria is reviewed. ► The relationship between intestinal helminths, gut microbiota and inflammatory bowel diseases is explored. ► IL-22 induced by helminths may enhance mucosal barrier function and restore the microbiota populations from dysbiosis.