title: Inflammatory mediators in Escherichia coli-induced mastitis in mice.
abstract: Escherichia coli (E. coli) infections in mouse mammary glands are rarely described and poorly characterized. In order to investigate the host immune response during coliform mastitis, several inflammatory parameters were evaluated at 24 and 48h following inoculation of mouse mammary glands with E. coli. Successfully challenged mice showed high values of the acute phase protein serum amyloid A (SAA) in blood. Systemic concentrations of the major inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were also increased as compared to control mice, while interleukin-1 (IL-1) levels remained negligible. Infected mammary glands showed a significant increase of all cytokine levels as compared to control glands. In accordance, mammary expression of the biologically inactive proform of IL-1beta was strongly up-regulated. Remarkably, data obtained in wild type as well as caspase-1 knockout mice showed that IL-1beta maturation seemed to occur independently from caspase-1. Finally, E. coli infection also triggered activation of the nuclear transcription factor-kappaB (NF-kappaB) in the mammary gland. In conclusion, the current study provides novel insights on the contribution of major regulatory proteins to the acute inflammatory host response at the local and systemic level during E. coli mastitis in mice.
authors.affiliation: Laboratory of Biochemistry, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium. Sofie.Notebaert@UGent.be
authors.forename: Sofie
authors.initials: S
authors.lastname: Notebaert
authors.forename: Dieter
authors.initials: D
authors.lastname: Demon
authors.forename: Tom
authors.initials: T
authors.lastname: Vanden Berghe
authors.forename: Peter
authors.initials: P
authors.lastname: Vandenabeele
authors.forename: Evelyne
authors.initials: E
authors.lastname: Meyer
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000276:immunology*; D004927:Escherichia coli Infections / Q000150:complications* / Q000276:immunology / Q000473:pathology; D005260:Female; D007375:Interleukin-1 / Q000276:immunology / Q000378:metabolism; D053583:Interleukin-1beta / Q000276:immunology / Q000378:metabolism; D015850:Interleukin-6 / Q000276:immunology / Q000378:metabolism; D008321:Mammary Glands, Animal / Q000276:immunology* / Q000382:microbiology* / Q000473:pathology; D008413:Mastitis / Q000276:immunology* / Q000382:microbiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000276:immunology / Q000378:metabolism; D000685:Serum Amyloid A Protein / Q000276:immunology / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D007375:Interleukin-1; D053583:Interleukin-1beta; D015850:Interleukin-6; D016328:NF-kappa B; D000685:Serum Amyloid A Protein; D014409:Tumor Necrosis Factor-alpha