title: Effect of submicron and nano-iron oxide particles on pulmonary immunity in mice.
abstract: Due to advances in nanotechnology, exposure to particle compounds in the workplace has become unavoidable. Assessment of their toxicity on health is an important occupational safety issue. This study was conducted in mice to investigate the toxicological effects of submicron and nano-iron oxide particles on pulmonary immune defences. In that purpose, we explored for the first time, inflammatory and immune responses in lung-associated lymph nodes. For each particle type, mice received either a single intratracheal instillation at different concentrations (250, 375, or 500μg/mouse) or four repeated instillations at 500μg/mouse each. Cytokine production, inflammatory and innate immune response, and humoral immune response were respectively assessed 1, 2, and 6 days after particle exposures. Both types of particles induced lung inflammation associated with increased cytokine productions in lymph node cell cultures and decreased pulmonary immune responses against sheep erythrocytes. Natural killer activity was not modified by particles. In comparison to single instillation, repeated instillations resulted in a reduction of inflammatory cell numbers in both bronchoalveolar lavages and pulmonary parenchyma. Moreover, the single instillation model demonstrated that, for a same dose, nano-iron oxide particles produced higher levels of inflammation and immunodepression than their submicron-sized counterparts.
authors.affiliation: Department of Pollutants and Health, National Institute for Research and Safety, 54519 Vandoeuvre-les-Nancy, France. masarin.ban@inrs.f
authors.forename: Masarin
authors.initials: M
authors.lastname: Ban
authors.forename: Isabelle
authors.initials: I
authors.lastname: Langonné
authors.forename: Nelly
authors.initials: N
authors.lastname: Huguet
authors.forename: Michèle
authors.initials: M
authors.lastname: Goutet
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005260:Female; D005290:Ferric Compounds / Q000633:toxicity*; D007371:Interferon-gamma / Q000032:analysis; D015850:Interleukin-6 / Q000032:analysis; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology; D008168:Lung / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D008198:Lymph Nodes / Q000187:drug effects / Q000276:immunology; D053768:Metal Nanoparticles; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D005290:Ferric Compounds; D015850:Interleukin-6; C000499:ferric oxide; D007371:Interferon-gamma