title: Arcobacter butzleri induces a pro-inflammatory response in THP-1 derived macrophages and has limited ability for intracellular survival.
abstract: Recent case reports have identified Arcobacter (A.) butzleri to be another emerging pathogen of the family Campylobacteraceae causing foodborne diseases. However, little is known about its interaction with the human immune system. As macrophages act as first defense against bacterial infections, we studied for the first time the impact of A. butzleri on human macrophages using THP-1 derived macrophages as an in vitro infection model. Our investigations considered the inflammatory response, intracellular survival and activation of caspases as potential virulence mechanisms employed by A. butzleri. Induction of IL-1α, IL-1ß, IL-6, IL-8, IL-12ß and TNFα demonstrated a pro-inflammatory response of infected macrophages towards A. butzleri. gentamycin protection assays revealed the ability of A. butzleri strains to survive and resist the hostile environment of phagocytic immune cells for up to 22 h. Moreover, initial activation of intitiator- (CASP8) as well as effector caspases (CASP3/7) was observed without the onset of DNA damage, suggesting a potential counter regulation. Intriguingly, we recognized distinct strain specific differences in invasion and survival capabilities. This suggests the existence of isolate dependent phenotype variations and different virulence potentials as known for other intestinal pathogens such as Salmonella enterica ssp.
authors.affiliation: Institute of Veterinary Biochemistry, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163 Berlin, Germany. Electronic address: Jennifer.zur.Bruegge@fu-berlin.de.
authors.forename: Jennifer
authors.initials: J
authors.lastname: zur Bruegge
authors.affiliation: Institute of Veterinary Biochemistry, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163 Berlin, Germany. Electronic address: Carlos.Hanisch@fu-berlin.de.
authors.forename: Carlos
authors.initials: C
authors.lastname: Hanisch
authors.affiliation: Institute of Veterinary Biochemistry, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163 Berlin, Germany. Electronic address: Ralf.Einspanier@fu-berlin.de.
authors.forename: Ralf
authors.initials: R
authors.lastname: Einspanier
authors.affiliation: Institute of Food Hygiene, Department of Veterinary Medicine, Freie Universität Berlin, Königsweg 69, 14163 Berlin, Germany. Electronic address: Thomas.Alter@fu-berlin.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Alter
authors.affiliation: Institute of Food Hygiene, Department of Veterinary Medicine, Freie Universität Berlin, Königsweg 69, 14163 Berlin, Germany. Electronic address: Greta.Goelz@fu-berlin.de.
authors.forename: Greta
authors.initials: G
authors.lastname: Gölz
authors.affiliation: Institute of Veterinary Biochemistry, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163 Berlin, Germany. Electronic address: soroush.sharbati@fu-berlin.de.
authors.forename: Soroush
authors.initials: S
authors.lastname: Sharbati
mesh_terms: D020640:Arcobacter / Q000276:immunology* / Q000502:physiology*; D020169:Caspases / Q000032:analysis; D002460:Cell Line; D016207:Cytokines / Q000032:analysis; D003593:Cytoplasm / Q000382:microbiology*; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000382:microbiology; D006801:Humans; D008264:Macrophages / Q000276:immunology* / Q000382:microbiology*; D050296:Microbial Viability
chemical_list: D016207:Cytokines; D020169:Caspases
keywords: Arcobacter butzleri; Caspase acivation; Inflammation; Intracellular survival; Macrophages