title: Animal shed Bacillus licheniformis spores possess allergy-protective as well as inflammatory properties.
abstract: BACKGROUND
  Numerous epidemiologic studies have demonstrated an allergy-protective effect of farm life early in childhood. It has been hypothesized that environmental exposure to microbes may contribute to this effect. Because of their small size and thereby their potential for deposition in lower airways of small children, bacterial spores may be candidates for such allergy-protective effects.
  
  
  OBJECTIVE
  To investigate immune responses elicited by exposure to Bacillus spores in experimental settings.
  
  
  METHODS
  Animal shed and mattress dusts were analyzed for bacteria and fungi by aerobic and anaerobic growth. Bacillus licheniformis, the most prominent microorganism found in these samples, was investigated with respect to spore specific stimulation of pattern recognition receptors, monocyte-derived dendritic cells and T(H)-cell polarization in vitro as well as to the prevention of asthma development in a mouse model of allergic asthma.
  
  
  RESULTS
  In vitro, B. licheniformis spores activated a T(H)1 cytokine expression profile. In vivo application of these spores resulted in less spore-specific but long-lasting immune activation preventing eosinophilia and goblet cell hyperplasia; however, they provoked an influx of neutrophils in lung tissue of asthmatic mice.
  
  
  CONCLUSIONS
  Bacterial spores may contribute to the allergy-protective properties of farming environments, but their persistence in the lung causes ongoing immune activation in mouse experiments.
authors.affiliation: Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Borstel, Germany.
authors.forename: Kay
authors.initials: K
authors.lastname: Vogel
authors.forename: Nicole
authors.initials: N
authors.lastname: Blümer
authors.forename: Melanie
authors.initials: M
authors.lastname: Korthals
authors.forename: Jessica
authors.initials: J
authors.lastname: Mittelstädt
authors.forename: Holger
authors.initials: H
authors.lastname: Garn
authors.forename: Markus
authors.initials: M
authors.lastname: Ege
authors.forename: Erika
authors.initials: E
authors.lastname: von Mutius
authors.forename: Sören
authors.initials: S
authors.lastname: Gatermann
authors.forename: Albrecht
authors.initials: A
authors.lastname: Bufe
authors.forename: Torsten
authors.initials: T
authors.lastname: Goldmann
authors.forename: Karin
authors.initials: K
authors.lastname: Schwaiger
authors.forename: Harald
authors.initials: H
authors.lastname: Renz
authors.forename: Sven
authors.initials: S
authors.lastname: Brandau
authors.forename: Johann
authors.initials: J
authors.lastname: Bauer
authors.forename: Holger
authors.initials: H
authors.lastname: Heine
authors.forename: Otto
authors.initials: O
authors.lastname: Holst
mesh_terms: D000818:Animals; D001249:Asthma / Q000276:immunology* / Q000517:prevention & control; D001407:Bacillus / Q000276:immunology* / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology / Q000382:microbiology; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism; D004391:Dust / Q000276:immunology*; D005260:Female; D020397:Goblet Cells / Q000166:cytology / Q000276:immunology / Q000382:microbiology; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology* / Q000517:prevention & control; D007249:Inflammation / Q000276:immunology; D007371:Interferon-gamma / Q000097:blood; D016753:Interleukin-10 / Q000097:blood; D015848:Interleukin-5 / Q000097:blood; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism; D008168:Lung / Q000166:cytology / Q000276:immunology / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D013171:Spores, Bacterial / Q000276:immunology* / Q000378:metabolism; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism
chemical_list: D004391:Dust; D015848:Interleukin-5; D016753:Interleukin-10; D007371:Interferon-gamma