Extracellular vesicles (EVs) in the perinatal window
- Spatio-temporal analysis of EV transfer between mammary cells
Extracellular vesicles (EVs) are nanoscaled structures secreted by cell types and identified in all kingdoms. Enclosed by a lipid bilayer, EVs carry bioactive molecules from one cell to another. They represent a general mechanism of intercellular communication and are deeply implicated in major physio-pathological processes such as the embryonic development, immune response, cancer and neurodegenerative diseases.
The transfer of EV in physiological condition is not well characterized, let alone the topology of the transfer at the single cell level. In the context of the mammary gland, I am thereby studying the spatio-temporal determinants of EVs transfer from one cell to another, based on a coculture assay that I have developed ealier (Burtey A. et al., The FASEB J. 2015; Frei D. et al. Sci. Rep. 2015). Results are currently providing answers to burning questions such as how many EVs are secreted by cells, how far they may travel and at which tempo.
The transfer of EV in physiological condition is not well characterized, let alone the topology of the transfer at the single cell level. In the context of the mammary gland, I am thereby studying the spatio-temporal determinants of EVs transfer from one cell to another, based on a coculture assay that I have developed ealier (Burtey A. et al., The FASEB J. 2015; Frei D. et al. Sci. Rep. 2015). Results are currently providing answers to burning questions such as how many EVs are secreted by cells, how far they may travel and at which tempo.
- The atomic composition of mammary and milk EVs and their metallic load
The composition of EVs has been studied in terms of proteins and lipids but rarely at the atomic level to study the metallic load of EVs.
Still in the context of the mammary gland, EVs secreted by epithelial cells or immune cells not only communicate short-distance within the gland but they are able to travel long distance through their secretion in milk and transfer from mother-to-offspring. So called milk-EVs remain mysterious structures but their presence has been proposed to benefit to offspring's health and development, particularly in terms of microbiota and digestive function.
Metals are essentials to newborn and provided by milk, and the role of EVs in carrying metals is not well understood.
By X-ray fluorescence microscopy at Synchrotron SOLEIL and inductively coupled plasma mass spectrometry at the laboratory of biological toxicology of Lariboisière Hospital (Paris, France), by Raman at the NABI lab (Univ. Paris Cité), we study metal elements in milk and milk-EVs. We investigate whether the EV atomic and molecular composition is influence by maternal exposure to pollutants, based on in vitro produced EVs, but also on animal milk purified EV from animals living in more or less pollution exposed settings, such as urban farms and urban grazing compared to countryside and mountain areas. These investigations may indicate whether milk-EVs may be a proxy for maternal pollutant exposure and whether the latter alters the former.
Still in the context of the mammary gland, EVs secreted by epithelial cells or immune cells not only communicate short-distance within the gland but they are able to travel long distance through their secretion in milk and transfer from mother-to-offspring. So called milk-EVs remain mysterious structures but their presence has been proposed to benefit to offspring's health and development, particularly in terms of microbiota and digestive function.
Metals are essentials to newborn and provided by milk, and the role of EVs in carrying metals is not well understood.
By X-ray fluorescence microscopy at Synchrotron SOLEIL and inductively coupled plasma mass spectrometry at the laboratory of biological toxicology of Lariboisière Hospital (Paris, France), by Raman at the NABI lab (Univ. Paris Cité), we study metal elements in milk and milk-EVs. We investigate whether the EV atomic and molecular composition is influence by maternal exposure to pollutants, based on in vitro produced EVs, but also on animal milk purified EV from animals living in more or less pollution exposed settings, such as urban farms and urban grazing compared to countryside and mountain areas. These investigations may indicate whether milk-EVs may be a proxy for maternal pollutant exposure and whether the latter alters the former.
Metal nanoparticles
Metal nanoparticles are nanosized crystals with fascinating and useful properties, such as colouring, photocatalytic, UV-filter, opacifying, fertilizer or pesticide, fongicide. They are massively manufactured in all industrial sectors and found in a vast number of daily life products. They are released in ecosystems indirectly upon waste degradation of these products, or directly upon use as remediation agent in waste water treatment plants or in air filters, or as fertilizer or pesticide on soils and crops. The development of mass spectrometry approaches enabling the detection of single nanoparticles in complex samples has been progressively revealing their presence in atmospheric particulate matter, in surface waters (lake, rivers, ponds, seas) including surface water used to produce drinking waters in Europe, and in soils, particularly those amended with sewage sludges. All living organisms are growingly exposed to these nanomaterials, calling for urgent assessment of their monitoring in human, livestock and food, particularly with regards to the number of studies demonstrating their toxicity to organisms ranging from bacteria to mammals.
Metal nanoparticles are nanosized crystals with fascinating and useful properties, such as colouring, photocatalytic, UV-filter, opacifying, fertilizer or pesticide, fongicide. They are massively manufactured in all industrial sectors and found in a vast number of daily life products. They are released in ecosystems indirectly upon waste degradation of these products, or directly upon use as remediation agent in waste water treatment plants or in air filters, or as fertilizer or pesticide on soils and crops. The development of mass spectrometry approaches enabling the detection of single nanoparticles in complex samples has been progressively revealing their presence in atmospheric particulate matter, in surface waters (lake, rivers, ponds, seas) including surface water used to produce drinking waters in Europe, and in soils, particularly those amended with sewage sludges. All living organisms are growingly exposed to these nanomaterials, calling for urgent assessment of their monitoring in human, livestock and food, particularly with regards to the number of studies demonstrating their toxicity to organisms ranging from bacteria to mammals.
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- In vitro and in vivo behavior of metal nanoparticles in cells and tissues
Part of the NanoMilk project, studying how metal nanoparticles are transferred from one cell to another is central to my research project.
Nano-toxico-genomics studies and genetic susceptibility to pollutants
- Genetic susceptibility
Because we demonstrated the existence of variations in the levels of titanium particles between individuals in maternal milk and between cow breeds, I am interested in understanding whether maternal genetic background may play a role in the levels of metal nanoparticles in milk, influencing the level of exposure to newborn and infants when it comes to animal milk.
- Nano - toxico - genomics
Once in offspring, metal nanoparticles may act on genome expression by disturbing how DNA is shaped, open or closed by histones, or by disturbing access to factors that regulate gene expression. This toxicogenomics studies are in their early days for metal nanoparticles, in particular for mammals in the perinatal window.