title: Elimination of Pseudomonas aeruginosa through Efferocytosis upon Binding to Apoptotic Cells.
abstract: For opportunistic pathogens such as Pseudomonas aeruginosa, the mucosal barrier represents a formidable challenge. Infections develop only in patients with altered epithelial barriers. Here, we showed that P. aeruginosa interacts with a polarized epithelium, adhering almost exclusively at sites of multi-cellular junctions. In these sites, numerous bacteria attach to an extruded apoptotic cell or apoptotic body. This dead cell tropism is independent of the type of cell death, as P. aeruginosa also binds to necrotic cells. We further showed that P. aeruginosa is internalized through efferocytosis, a process in which surrounding epithelial cells engulf and dispose of extruded apoptotic cells. Intracellularly, along with apoptotic cell debris, P. aeruginosa inhabits an efferocytic phagosome that acquires lysosomal features, and is finally killed. We propose that elimination of P. aeruginosa through efferocytosis is part of a host defense mechanism. Our findings could be relevant for the study of cystic fibrosis, which is characterized by an exacerbated number of apoptotic cells and ineffective efferocytosis.
authors.affiliation: Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde (IIB-INTECH), Universidad Nacional de San Martín, Consejo Nacional de Investigaciones Científicas y Técnicas (UNSAM-CONICET), San Martín, Buenos Aires, Argentina.
authors.forename: Darío
authors.identifier: http://orcid.org/0000-0003-3793-5208
authors.initials: D
authors.lastname: Capasso
authors.affiliation: Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde (IIB-INTECH), Universidad Nacional de San Martín, Consejo Nacional de Investigaciones Científicas y Técnicas (UNSAM-CONICET), San Martín, Buenos Aires, Argentina.
authors.forename: María Victoria
authors.initials: MV
authors.lastname: Pepe
authors.affiliation: Institut Pasteur de Montevideo, Montevideo, Uruguay.
authors.forename: Jéssica
authors.identifier: http://orcid.org/0000-0002-6475-9273
authors.initials: J
authors.lastname: Rossello
authors.affiliation: Institut Pasteur de Montevideo, Montevideo, Uruguay.
authors.forename: Paola
authors.identifier: http://orcid.org/0000-0003-3027-4398
authors.initials: P
authors.lastname: Lepanto
authors.affiliation: Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde (IIB-INTECH), Universidad Nacional de San Martín, Consejo Nacional de Investigaciones Científicas y Técnicas (UNSAM-CONICET), San Martín, Buenos Aires, Argentina.
authors.forename: Paula
authors.initials: P
authors.lastname: Arias
authors.affiliation: Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde (IIB-INTECH), Universidad Nacional de San Martín, Consejo Nacional de Investigaciones Científicas y Técnicas (UNSAM-CONICET), San Martín, Buenos Aires, Argentina.
authors.forename: Valentina
authors.identifier: http://orcid.org/0000-0002-2451-7632
authors.initials: V
authors.lastname: Salzman
authors.affiliation: Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde (IIB-INTECH), Universidad Nacional de San Martín, Consejo Nacional de Investigaciones Científicas y Técnicas (UNSAM-CONICET), San Martín, Buenos Aires, Argentina.
authors.forename: Arlinet
authors.initials: A
authors.lastname: Kierbel
mesh_terms: D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D004285:Dogs; D004847:Epithelial Cells / Q000382:microbiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D061985:Madin Darby Canine Kidney Cells; D046529:Microscopy, Electron, Transmission; D010587:Phagocytosis / Q000276:immunology*; D011552:Pseudomonas Infections / Q000276:immunology*; D011550:Pseudomonas aeruginosa / Q000276:immunology