title: Internalization of SiO₂ nanoparticles by alveolar macrophages and lung epithelial cells and its modulation by the lung surfactant substitute Curosurf.
abstract: Because of an increasing exposure to environmental and occupational nanoparticles (NPs), the potential risk of these materials for human health should be better assessed. Since one of the main routes of entry of NPs is via the lungs, it is of paramount importance to further characterize their impact on the respiratory system. Here, we have studied the uptake of fluorescently labeled SiO₂ NPs (50 and 100 nm) by epithelial cells (NCI-H292) and alveolar macrophages (MHS) in the presence or absence of pulmonary surfactant. The quantification of NP uptake was performed by measuring cell-associated fluorescence using flow cytometry and spectrometric techniques in order to identify the most suitable methodology. Internalization was shown to be time and dose dependent, and differences in terms of uptake were noted between epithelial cells and macrophages. In the light of our observations, we conclude that flow cytometry is a more reliable technique for the study of NP internalization, and importantly, that the hydrophobic fraction of lung surfactant is critical for downregulating NP uptake in both cell types.
authors.affiliation: Laboratory of Molecular and Cellular Responses to Xenobiotics, Unit of Functional and Adaptive Biology EAC CNRS 4413, Sorbonne Paris Cité, Univ Paris Diderot, 5 rue Thomas Mann, 75013 Paris, France. sandra.vranic@univ-paris-diderot.fr
authors.forename: Sandra
authors.initials: S
authors.lastname: Vranic
authors.forename: Ignacio
authors.initials: I
authors.lastname: Garcia-Verdugo
authors.forename: Cécile
authors.initials: C
authors.lastname: Darnis
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Sallenave
authors.forename: Nicole
authors.initials: N
authors.lastname: Boggetto
authors.forename: Francelyne
authors.initials: F
authors.lastname: Marano
authors.forename: Sonja
authors.initials: S
authors.lastname: Boland
authors.forename: Armelle
authors.initials: A
authors.lastname: Baeza-Squiban
mesh_terms: D000818:Animals; D001688:Biological Products / Q000494:pharmacology*; D002460:Cell Line; D004784:Environmental Monitoring / Q000379:methods*; D004847:Epithelial Cells / Q000378:metabolism*; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D008168:Lung / Q000378:metabolism; D016676:Macrophages, Alveolar / Q000378:metabolism*; D051379:Mice; D018613:Microscopy, Confocal; D053758:Nanoparticles / Q000008:administration & dosage*; D010316:Particle Size; D010743:Phospholipids / Q000494:pharmacology*; D011663:Pulmonary Surfactants / Q000494:pharmacology*; D012822:Silicon Dioxide / Q000378:metabolism; D013053:Spectrophotometry / Q000379:methods
chemical_list: D001688:Biological Products; D010743:Phospholipids; D011663:Pulmonary Surfactants; D012822:Silicon Dioxide; C068291:poractant alfa