Thesis presented June 28, 2022

Abstract:
Nanomaterials are used in the industry to improve the quality of many different products (color, texture or efficiency). For example, synthetic amorphous silica are used in various applications such as cosmetics, food or rubber reinforcement. These broad uses increase human exposure and thus the potential risk related to their short- and long-term toxicity. These potential risks have to be investigated, in a global context of multi-exposure, as encountered in human populations. The scenario multiplicity makes the use of animal models difficult, because of ethical and economical reasons. This is why the experiments will be conducted on in vitro macrophage models (RAW264.7 and J774A.1 and mouse primary macrophages) as this cell type is an important cell target in toxicology of particulate materials. Herein, the effect of different exposure scenarii of macrophages to silica nanomaterials will be investigated: the acute exposure for 24h, the chronic exposure for some days and the recovery scenario which consists in an exposure followed by a time period without nanomaterials, which is a fundamental parameter in nanotoxicology. The bioaccumulation of nanomaterials and the persistence of their effect will be studied. The experiments which will be carried out include the viability assay and functional tests (phagocytosis, NO and reactive oxygen species dosages, production of pro and anti-inflammatory cytokines) using flow cytometry, microscopy and spectrophotometry.

Keywords:
in vitro, macrophages, bioaccumulation, exposure scenarii

On-line thesis.