title: Host Stress Drives Salmonella Recrudescence.
abstract: Host stress is well known to result in flare-ups of many bacterial, viral and parasitic infections. The mechanism by which host stress is exploited to increase pathogen loads, is poorly understood. Here we show that Salmonella enterica subspecies enterica serovar Typhimurium employs a dedicated mechanism, driven by the scsA gene, to respond to the host stress hormone cortisol. Through this mechanism, cortisol increases Salmonella proliferation inside macrophages, resulting in increased intestinal infection loads in DBA/2J mice. ScsA directs overall Salmonella virulence gene expression under conditions that mimic the intramacrophagic environment of Salmonella, and stimulates the host cytoskeletal alterations that are required for increased Salmonella proliferation inside cortisol exposed macrophages. We thus provide evidence that in a stressed host, the complex interplay between a pathogen and its host endocrine and innate immune system increases intestinal pathogen loads to facilitate pathogen dispersal.
authors: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Elin
authors: E
authors: Verbrugghe
authors: Laboratory for Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
authors: Maarten
authors: M
authors: Dhaenens
authors: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Bregje
authors: B
authors: Leyman
authors: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Filip
authors: F
authors: Boyen
authors: Gut Health and Food Safety Programme, Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, United Kingdom.
authors: Neil
authors: N
authors: Shearer
authors: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Alexander
authors: A
authors: Van Parys
authors: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Roel
authors: R
authors: Haesendonck
authors: Department of Biology, Nematology Research Unit, Faculty of Sciences, Ghent University, Ghent, Belgium.
authors: Wim
authors: W
authors: Bert
authors: Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Herman
authors: H
authors: Favoreel
authors: Laboratory for Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
authors: Dieter
authors: D
authors: Deforce
authors: Gut Health and Food Safety Programme, Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, United Kingdom.
authors: Arthur
authors: A
authors: Thompson
authors: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Freddy
authors: F
authors: Haesebrouck
authors: Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors: Frank
authors: F
authors: Pasmans
mesh_terms: D000818:Animals; D002460:Cell Line; D015964:Gene Expression Regulation, Bacterial / Q000276:immunology*; D006854:Hydrocortisone / Q000276:immunology; D016676:Macrophages, Alveolar / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D051379:Mice; D012480:Salmonella Infections / Q000276:immunology*; D012486:Salmonella typhimurium / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity*; D013312:Stress, Physiological / Q000276:immunology*; D013552:Swine; D037521:Virulence Factors / Q000235:genetics / Q000276:immunology*
chemical_list: D037521:Virulence Factors; D006854:Hydrocortisone