title: Secretory component: a new role in secretory IgA-mediated immune exclusion in vivo.
abstract: Secretory immunoglobulin (Ig) A (SIgA) is essential in protecting mucosal surfaces. It is composed of at least two monomeric IgA molecules, covalently linked through the J chain, and secretory component (SC). We show here that a dimeric/polymeric IgA (IgA(d/p)) is more efficient when bound to SC in protecting mice against bacterial infection of the respiratory tract. We demonstrate that SC ensures, through its carbohydrate residues, the appropriate tissue localization of SIgA by anchoring the antibody to mucus lining the epithelial surface. This in turn impacts the localization and the subsequent clearance of bacteria. Thus, SC is directly involved in the SIgA function in vivo. Therefore, binding of IgA(d/p) to SC during the course of SIgA-mediated mucosal response constitutes a crucial step in achieving efficient protection of the epithelial barrier by immune exclusion.
authors.affiliation: Unité de Pathogénie Microbienne Moléculaire, INSERM U 389, France. phalipon@pasteur.fr
authors.forename: Armelle
authors.initials: A
authors.lastname: Phalipon
authors.forename: Ana
authors.initials: A
authors.lastname: Cardona
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Kraehenbuhl
authors.forename: Léna
authors.initials: L
authors.lastname: Edelman
authors.forename: Philippe J
authors.initials: PJ
authors.lastname: Sansonetti
authors.forename: Blaise
authors.initials: B
authors.lastname: Corthésy
mesh_terms: D000818:Animals; D004405:Dysentery, Bacillary / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D006031:Glycosylation; D018928:Immunity, Mucosal; D007071:Immunoglobulin A, Secretory / Q000032:analysis / Q000276:immunology*; D008168:Lung / Q000276:immunology / Q000473:pathology; D051379:Mice; D009296:Nasal Cavity / Q000276:immunology; D012141:Respiratory Tract Infections / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D012635:Secretory Component / Q000502:physiology*
chemical_list: D007071:Immunoglobulin A, Secretory; D012635:Secretory Component