title: Caspase-3-dependent phagocyte death during systemic Salmonella enterica serovar Typhimurium infection of mice.
abstract: Growth of Salmonella enterica in mammalian tissues results from continuous spread of bacteria to new host cells. Our previous work indicated that infective S. enterica are liberated from host cells via stochastic necrotic burst independently of intracellular bacterial numbers. Here we report that liver phagocytes can undergo apoptotic caspase-3-mediated cell death in vivo, with apoptosis being a rare event, more prevalent in heavily infected cells. The density-dependent apoptotic cell death is likely to constitute an alternative mechanism of bacterial spread as part of a bet-hedging strategy, ensuring an ongoing protective intracellular environment in which some bacteria can grow and persist.
authors.affiliation: Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, UK. ajg60@cam.ac.uk
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Grant
authors.forename: Mark
authors.initials: M
authors.lastname: Sheppard
authors.forename: Rob
authors.initials: R
authors.lastname: Deardon
authors.forename: Sam P
authors.initials: SP
authors.lastname: Brown
authors.forename: Gemma
authors.initials: G
authors.lastname: Foster
authors.forename: Clare E
authors.initials: CE
authors.lastname: Bryant
authors.forename: Duncan J
authors.initials: DJ
authors.lastname: Maskell
authors.forename: Pietro
authors.initials: P
authors.lastname: Mastroeni
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000276:immunology*; D053148:Caspase 3 / Q000276:immunology*; D053938:DNA Fragmentation; D005260:Female; D020287:In Situ Nick-End Labeling; D008099:Liver / Q000276:immunology / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence / Q000379:methods; D010586:Phagocytes / Q000276:immunology* / Q000382:microbiology; D012481:Salmonella Infections, Animal / Q000276:immunology* / Q000382:microbiology; D012486:Salmonella typhimurium / Q000302:isolation & purification*; D051197:Toll-Like Receptor 4 / Q000378:metabolism
chemical_list: C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D053148:Caspase 3