title: The front line of enteric host defense against unwelcome intrusion of harmful microorganisms: mucins, antimicrobial peptides, and microbiota.
abstract: The intestinal tract is a complex ecosystem that combines resident microbiota and the cells of various phenotypes with complex metabolic activities that line the epithelial wall. The intestinal cells that make up the epithelium provide physical and chemical barriers that protect the host against the unwanted intrusion of microorganisms that hijack the cellular molecules and signaling pathways of the host and become pathogenic. Some of the organisms making up the intestinal microbiota also have microbicidal effects that contribute to the barrier against enteric pathogens. This review describes the two cell lineages present in the intestinal epithelium: the goblet cells and the Paneth cells, both of which play a pivotal role in the first line of enteric defense by producing mucus and antimicrobial peptides, respectively. We also analyze recent insights into the intestinal microbiota and the mechanisms by which some resident species act as a barrier to enteric pathogens. Moreover, this review examines whether the cells producing mucins or antimicrobial peptides and the resident microbiota act in partnership and whether they function individually and/or synergistically to provide the host with an effective front line of defense against harmful enteric pathogens.
authors.affiliation: Unité 756 INSERM, Faculté de Pharmacie Paris XI, Signalisation et Physiopathologie des Cellules Epithéliales, Institut National de la Santé et de la Recherche Médicale, F-92296 Chātenay-Malabry, France.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Liévin-Le Moal
authors.forename: Alain L
authors.initials: AL
authors.lastname: Servin
mesh_terms: D000818:Animals; D000898:Antibiosis; D023181:Antimicrobial Cationic Peptides / Q000276:immunology* / Q000378:metabolism*; D001419:Bacteria / Q000145:classification / Q000254:growth & development / Q000378:metabolism; D018407:Bacterial Physiological Phenomena; D020397:Goblet Cells / Q000378:metabolism; D006801:Humans; D007113:Immunity, Innate; D007410:Intestinal Diseases / Q000276:immunology* / Q000382:microbiology* / Q000503:physiopathology / Q000517:prevention & control; D007413:Intestinal Mucosa / Q000276:immunology* / Q000382:microbiology* / Q000503:physiopathology; D009077:Mucins / Q000276:immunology* / Q000378:metabolism*; D019879:Paneth Cells / Q000378:metabolism; D013045:Species Specificity
chemical_list: D023181:Antimicrobial Cationic Peptides; D009077:Mucins