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International audience; Background: Inflammasomes are large protein complexes that assemble in the cytosol in response to danger such as tissue damage or infection. Following activation, inflammasomes trigger cell death and the release of biologically active forms of pro-inflammatory cytokines interleukin (IL)-1β and IL-18. NOD-like receptor family pyrin domain containing 6 (NLRP6) inflammasome is required for IL-18 secretion by intestinal epithelial cells, macrophages, and T cells, contributing to homeostasis and self-defense against pathogenic microbes. However, the involvement of NLRP6 in type 2 lung inflammation remains elusive.Methods: Wild-type (WT) and Nlrp6−/− mice were used. Birch pollen extract (BPE)-induced allergic lung inflammation, eosinophil recruitment, Th2-related cytokine and chemokine production, airway hyperresponsiveness, and lung histopathology, Th2 cell differentiation, GATA3, and Th2 cytokines expression, were determined. Nippostrongylus brasiliensis (Nb) infection, worm count in intestine, type 2 innate lymphoid cell (ILC2), and Th2 cells in lungs were evaluated.Results: We demonstrate in Nlrp6−/− mice that a mixed Th2/Th17 immune responses prevailed following birch pollen challenge with increased eosinophils, ILC2, Th2, and Th17 cell induction and reduced IL-18 production. Nippostrongylus brasiliensis infected Nlrp6−/− mice featured enhanced early expulsion of the parasite due to enhanced type 2 immune responses compared to WT hosts. In vitro, NLRP6 repressed Th2 polarization, as shown by increased Th2 cytokines and higher expression of the transcription factor GATA3 in the absence of NLRP6. Exogenous IL-18 administration partially reduced the enhanced airways inflammation in Nlrp6−/− mice.Conclusions: In summary, our data identify NLRP6 as a negative regulator of type 2 immune responses.

International audience; La recherche concernant la fabrication du livre médiéval est abordées par le biais de l'analyse des matériaux du décor et de l'écrit à l'aide de méthodes applicables in situ et non destructives. Les dernières investigations liées à l'approche codicologique concernent des manuscrits conservés au Centre d'étude de la civilisation et des arts islamiques de Raqqada à Kairouan et issus d'un fonds reconstitués de corans dont la période de fabrication s'inscrit entre le IXe s. et le début du XIe s. L'analyse des résultats obtenus conduisent, par une approche comparative, à envisager des groupements de manuscrits relativement aux travaux précédemment réalisés sur deux autres corpus.

The use of Raman microanalysis, together with related techniques of absorption microspectrophotometry and fluorometric microanalysis, for investigating dyes and pigments is described. Examples are given of the identification of a number of synthetic and traditional colorants.

International audience; By measuring the oscillation frequencies of atoms in the visible region, Raman spectrometry makes it possible to determine the polyatomic structure (ions, molecules, crystals) of organic or mineral compounds. The instrumentation has recently developed to such an extent that measurements can now be carried out on samples of very small dimensions (down to a few microns). This is done using the Raman laser microprobe, whose role in microspectrometry is briefly described. This method of analysis is non-destructive. It has been used successfully to identify various ancient pigments encountered on objects in course of conservation. The results obtained for samples of azurite and malachite are given, as well as a demonstration of the method’s application for the identification of azurite on a fragment of illuminated manuscript dating from the fifteenth century.