title: Some peculiarities of pulmonary clearance mechanisms in rats after intratracheal instillation of magnetite (Fe3O4) suspensions with different particle sizes in the nanometer and micrometer ranges: are we defenseless against nanoparticles?
abstract: We studied differences between phagocytic responses to nanoparticles (NPs) versus microparticles in the pulmonary region by synthesizing magnetite of different sizes and instilling suspensions of these particles intratracheally into rats' lungs. Ten and 50 nm particles caused a greater increase in cell counts of the bronchoalveolar lavage fluid (BALF) than the instillation of microparticles. The response to 10 nm particles was weaker than to 50 nm ones, and the smaller NPs were more cytotoxic; both were more cytotoxic than the microparticles. Phagocytic activity was also studied using optical and atomic force microscopy. Phagocytes were more "loaded" in the lungs instilled with 10 nm particles as compared with those instilled with 50 nm particles; NPs of both sizes were engulfed more avidly than microparticles. We found in a separate comparative experiment that magnetite NPs were more cytotoxic than titanium dioxide and quartz suspensions having particle size distribution typical of industrial dusts.
authors.affiliation: Medical Research Center for Prophylaxis and Health Protection in Industrial Workers, Ekaterinburg, Russian Federation. bkatsnelson@etel.ru
authors.forename: Boris
authors.initials: B
authors.lastname: Katsnelson
authors.forename: Larissa I
authors.initials: LI
authors.lastname: Privalova
authors.forename: Sergey V
authors.initials: SV
authors.lastname: Kuzmin
authors.forename: Tamara D
authors.initials: TD
authors.lastname: Degtyareva
authors.forename: Marina P
authors.initials: MP
authors.lastname: Sutunkova
authors.forename: Olga S
authors.initials: OS
authors.lastname: Yeremenko
authors.forename: Ilzira A
authors.initials: IA
authors.lastname: Minigalieva
authors.forename: Ekaterina P
authors.initials: EP
authors.lastname: Kireyeva
authors.forename: Mark Y
authors.initials: MY
authors.lastname: Khodos
authors.forename: Alisa N
authors.initials: AN
authors.lastname: Kozitsina
authors.forename: Natalya A
authors.initials: NA
authors.lastname: Malakhova
authors.forename: Julia A
authors.initials: JA
authors.lastname: Glazyrina
authors.forename: Vladimir Y
authors.initials: VY
authors.lastname: Shur
authors.forename: Eugene I
authors.initials: EI
authors.lastname: Shishkin
authors.forename: Ekaterina V
authors.initials: EV
authors.lastname: Nikolaeva
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D005260:Female; D005290:Ferric Compounds / Q000008:administration & dosage / Q000009:adverse effects*; D008168:Lung / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D016676:Macrophages, Alveolar / Q000187:drug effects / Q000276:immunology; D058185:Magnetite Nanoparticles / Q000008:administration & dosage / Q000009:adverse effects*; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology; D010316:Particle Size; D010587:Phagocytosis; D051381:Rats
chemical_list: D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C000499:ferric oxide