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Biology subjects

Huaux, F.

Publications and source records attributed to Huaux, F..

2 recordsLinked to original sources

Extracellular Vesicle-Enriched Secretome from Mesenchymal Stromal Cells Protects Against Chemically, Particulate-, and Ischemia-Induced Innate-Immunity Induced Inflammation

Mesenchymal stromal cells (MSCs) are multipotent cells with well-established regenerative and immunomodulatory properties, making them promising candidates for the treatment of inflammatory diseases. However, the therapeutic effects of MSCs are largely mediated by their secretome, particularly extracellular vesicles (EVs), which deliver bioactive molecules capable of modulating inflammatory responses. We generated an extracellular vesicle-enriched secretome (EVES) from MSCs under scalable, Good Manufacturing Practice (GMP)-compliant conditions and assessed its therapeutic efficacy in diverse disease models, including lung inflammation and kidney injury induced by distinct innate immune stimuli. EVES was isolated from the secretome of umbilical cord blood-derived MSCs cultured in a chemically defined medium. In vitro, EVES significantly and dose-dependently attenuated cytokine release from airway epithelial cells and macrophages stimulated with inflammatory agents such as lipopolysaccharide or reactive particles. In murine models of lung inflammation, EVES reduced neutrophil infiltration and suppressed multiple cytokines and chemokines in a dose-dependent manner. In models of kidney injury, EVES enhanced tubular epithelial cell proliferation, improved renal histology, and markedly reduced tubular necrosis following ischemia-reperfusion injury. Collectively, these findings demonstrate that MSC-derived EVES exhibits robust and broad-spectrum therapeutic activity across multiple disease contexts driven by innate immune activation, supporting its potential as a scalable, cell-free therapeutic platform.

cell biology↗

BRAFV600E expression in thyrocytes causes recruitment of immunosuppressive STABILIN-1 macrophages

Papillary thyroid carcinoma (PTC) is the most frequent histological subtype of thyroid cancers (TC), and BRAFV600E genetic alteration is found in 60% of this endocrine cancer. This oncogene is associated with poor prognosis, resistance to radioiodine therapy and tumor progression. Histological follow-up by anatomo-pathologists reveals that 2/3 of surgically-removed thyroids do not present malignant lesions. Continued fundamental research into the molecular mechanisms of TC downstream of BRAFV600E remains thus central to better understand the clinical behavior of these tumors. To study PTC, we used a mouse model in which expression of BRAFV600E is specifically switched on in thyrocytes by doxycycline administration. Upon daily intraperitoneal doxycycline injection, thyroid tissue rapidly acquired histological features mimicking human PTC. Transcriptomic analysis revealed major changes in immune signaling pathways upon BRAFV600E induction. Multiplex immunofluorescence confirmed the abundant recruitment of macrophages, among which a population of LYVE-1+/CD206+/STABILIN-1+ was dramatically increased. By genetically inactivating the gene coding for the scavenger receptor STABILIN-1, we showed an increase of CD8+ T cells in this in situ BRAFV600E dependent TC. Finally, we demonstrated the presence of CD206+/STABILIN-1+ macrophages in human thyroid pathologies. Altogether, we revealed the recruitment of immunosuppressive STABILIN-1 macrophages a PTC mouse model and the relevance of these observations in human thyroid tissues.

cancer biology↗