Entity

Time filter

Source Type


Pailleux M.,LINA Laboratoire Interdisciplinaire dEtude des Nanoparticules Aerosolisees | Pailleux M.,Ecole Nationale Superieure des Mines de Saint - Etienne CMP | Pourchez J.,LINA Laboratoire Interdisciplinaire dEtude des Nanoparticules Aerosolisees | Pourchez J.,Ecole Nationale Superieure des Mines de Saint - Etienne CMP | And 7 more authors.
Journal of Physics: Conference Series | Year: 2011

This work aims at developping a multidisciplinary approach to highlight the correlation between the toxicity of alumina engineered nanoparticles (NP) and their physicochemical characteristics. Accuracy of measurements depends on cell production after contact with particles, but also depends on the ability of biomolecules to get adsorbed on the NP [1]. That's why, mechanisms of biomolecules adsorption on NP must be fully understood to avoid misinterpretation of data. Source


Leclerc L.,LINA Laboratoire Interdisciplinaire dEtude des Nanoparticules Aerosolisees | Leclerc L.,Ecole Nationale Superieure des Mines de Saint - Etienne CMP | Boudard D.,LINA Laboratoire Interdisciplinaire dEtude des Nanoparticules Aerosolisees | Boudard D.,Jean Monnet University | And 11 more authors.
Journal of Physics: Conference Series | Year: 2011

The aim of this work was the development of pH-sensor-NP allowing the quantification of the amount of NP phagocytosed by macrophages. Two types of fluorescent NP with variable and well-characterized sizes and chemicals coatings have been synthesized: NP with a FITC core (FITC-NP): green fluorescence (control). FITC-NP functionalized with a pH sensitive probe (pH-sensor-NP): green fluorescence of the FITC and red fluorescence of the pH probe in acidic conditions. Our pH-sensor-NP model was first validated in acellular conditions. They were then incubated with a macrophage cell line allowing distinction and quantification of internalized NP with no major effects on biological toxicity. Source


Leclerc L.,LINA Laboratoire Interdisciplinaire dEtude des Nanoparticules Aerosolisees | Leclerc L.,French Institute of Health and Medical Research | Leclerc L.,Ecole Nationale Superieure des Mines de Saint - Etienne CMP | Boudard D.,LINA Laboratoire Interdisciplinaire dEtude des Nanoparticules Aerosolisees | And 16 more authors.
Inhalation Toxicology | Year: 2010

Background: The use of micro- or nanometric particles is in full expansion for the development of new technologies. These particles may exhibit variable toxicity levels depending on their physicochemical characteristics. We focused our attention on macrophages (MA), the main target cells of the respiratory system responsible for the phagocytosis of the particles. The quantification of the amount of phagocytosed particles seems to be a major element for a better knowledge of toxicity mechanisms. The aim of this study was to develop a quantitative evaluation of uptake using both flow cytometry (FCM) and confocal microscopy to distinguish entirely engulfed fluorescent microsized particles from those just adherent to the cell membrane and to compare these data to in vitro toxicity assessments. Methods: Fluorescent particles of variable and well-characterised sizes and surface coatings were incubated with MA (RAW 264.7 cell line). Analyses were performed using confocal microscopy and FCM. The biological toxicity of the particles was evaluated [lactate dehydrogenase (LDH) release, tumor necrosis factor (TNF)-α, and reactive oxygen species (ROS) production]. Results and conclusion: Confocal imaging allowed visualization of entirely engulfed beads. The amount of phagocytic cells was greater for carboxylate 2-m beads (49±11%) than for amine 1-m beads (18±5%). Similarly, side scatter geometric means, reflecting cellular complexity, were 446±7 and 139±12, respectively. These results confirm that the phagocytosis level highly depends on the size and surface chemical groups of the particles. Only TNF-α and global ROS production varied significantly after 24-h incubation. There was no effect on LDH and H2O2 production. © 2010 Informa Healthcare USA, Inc. Source

Discover hidden collaborations