title: Methanosphaera stadtmanaeinduces a type IV hypersensitivity response in a mouse model of airway inflammation.
abstract: Despite improved awareness of work-related diseases and preventive measures, many workers are still at high risk of developing occupational hypersensitivity airway diseases. This stems from a lack of knowledge of bioaerosol composition and their potential effects on human health. Recently, archaea species were identified in bioaerosols, raising the possibility that they play a major role in exposure-related pathology. Specifically,Methanosphaera stadtmanae(MSS) andMethanobrevibacter smithii(MBS) are found in high concentrations in agricultural environments and respiratory exposure to crude extract demonstrates immunomodulatory activity in mice. Nevertheless, our knowledge of the specific impact of methanogens exposure on airway immunity and their potential to induce airway hypersensitivity responses in workers remains scant. Analysis of the lung mucosal response to methanogen crude extracts in mice demonstrated that MSS and MBS predominantly induced TH17 airway inflammation, typical of a type IV hypersensitivity response. Furthermore, the response to MSS was associated with antigen-specific IgG1and IgG2aproduction. However, despite the presence of eosinophils after MSS exposure, only a weak TH2 response and no airway hyperresponsiveness were observed. Finally, using eosinophil and mast cell-deficient mice, we confirmed that these cells are dispensable for the TH17 response to MSS, although eosinophils likely contribute to the exacerbation of inflammatory processes induced by MSS crude extract exposure. We conclude that, as MSS induces a clear type IV hypersensitivity lung response, it has the potential to be harmful to workers frequently exposed to this methanogen, and that preventive measures should be taken to avoid chronic hypersensitivity disease development in workers.
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada.
authors.forename: Emilie
authors.initials: E
authors.lastname: Bernatchez
authors.affiliation: The Biomedical Research Center, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Gold
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada.
authors.forename: Anick
authors.initials: A
authors.lastname: Langlois
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada.
authors.forename: Pascale
authors.initials: P
authors.lastname: Blais-Lecours
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada.
authors.forename: Magali
authors.initials: M
authors.lastname: Boucher
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada.
authors.forename: Caroline
authors.initials: C
authors.lastname: Duchaine
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Marsolais
authors.affiliation: The Biomedical Research Center, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Kelly M
authors.initials: KM
authors.lastname: McNagny
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada marie-renee.blanchet@criucpq.ulaval.ca.
authors.forename: Marie-Renée
authors.initials: MR
authors.lastname: Blanchet
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006967:Hypersensitivity / Q000382:microbiology*; D007074:Immunoglobulin G / Q000032:analysis; D007249:Inflammation / Q000382:microbiology*; D008168:Lung / Q000382:microbiology*; D017013:Methanobacteriaceae; D051379:Mice; D012130:Respiratory Hypersensitivity / Q000382:microbiology*
chemical_list: D007074:Immunoglobulin G
keywords: Eosinophils; IL‐17; hypersensitivity response; lung; methanogens