A Guide for Ex Vivo Handling and storage of stool samples Intended for Fecal Microbiota transplantation

International audienceOwing to the growing recognition of the gut microbiota as a main partner of human health, we are expecting that the number of indications for fecal microbiota transplantation (FMt) will increase. Thus, there is an urgent need for standardization of the entire process of fecal transplant production. This study provides a complete standardized procedure to prepare and store live and ready-to-use transplants that meet the standard requirements of good practices to applied use in pharmaceutical industry. We show that, if time before transformation to transplants would exceed 24 hours, fresh samples should not be exposed to temperatures above 20 °C, and refrigeration at 4 °C can be a safe solution. Oxygen-free atmosphere was not necessary and simply removing air above collected samples was sufficient to preserve viability. Transplants prepared in maltodextrin-trehalose solutions, stored in a-80 °C standard freezer and then rapidly thawed at 37 °C, retained the best revivification potential as proven by 16S rRNA profiles, metabolomic fingerprints, and flow cytometry assays over a 3-month observation period. Maltodextrin-trehalose containing cryoprotectants were also efficient in preserving viability of lyophilized transplants, either in their crude or purified form, an option that can be attractive for fecal transplant biobanking and oral formulation

Analyse des parametres immunologiques chez des patients cancereux traites par anticorps monoclonaux seuls ou associes a l'interferon Gamma

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

La fermentation colique des fibres alimentaires influence notre tube digestif

La santé en pays de la LoireNational audienc

Impact of newly developed metagenomic tools on our knowledge of the gut microbiota and its role in human health: diagnostic and therapeutic issues

Over the last years, our vision of the intestinal microbiota and its contribution to human physiology has been fully revisited, thanks to metagenomics. Next generation sequencing allowed a full characterization of the microbiome. Quantitative metagenomic permitted a deep understanding of the intestinal ecosystem, its structure, and potential dysbiosis in several human pathologies. The microbiome may be used as biomarker of disease or of risk to progress toward a disease. A good understanding of the mechanisms of interaction between gut microbiota and its host is needed; functional metagenomic is a useful tool to identify genes and metabolites able to interact with host's cells. Overall, the microbiome science that is developing opens new avenue for diagnosis, discovery of new drugs and potential therapeutic approaches. It is also a target for modulation by food, with potential impact on health.Notre vision du microbiote intestinal et de sa contribution à la physiologie humaine a été complètement revisitée grâce aux nouveaux outils de métagénomique. Le séquençage de dernière génération a permis d’identifier les espèces dominantes présentes dans l’intestin par des approches ciblées sur l’ADN ribosomal 16S, mais également de séquencer l’ensemble des gènes présents et donc d’accéder à leurs fonctions. La métagénomique quantitative a conduit à une caractérisation précise de l’écosystème intestinal, de sa structuration et de sa perturbation dans certaines pathologies. Le microbiome apparaît comme un outil diagnostique voire pronostique d’intérêt. La compréhension des mécanismes par lesquels le microbiote interagit avec nos cellules est indispensable ; la métagénomique fonctionnelle constitue un outil essentiel à l’identification des fonctions du microbiote. La prise en compte du microbiote et ses applications en santé humaine constituent un domaine en plein développement

Humans as holobionts: implications for prevention and therapy

International audienceThe human gut microbiota is increasingly recognized for its important or even decisive role in health. As it becomes clear that microbiota and host mutually affect and depend on each other in an intimate relationship, a holistic view of the gut microbiota-host association imposes itself. Ideally, a stable state of equilibrium, homeostasis, is maintained and serves health, but signs are that perturbation of this equilibrium beyond the limits of resilience can propel the system into an alternative stable state, a pre-disease state, more susceptible to the development of chronic diseases. The microbiota-host equilibrium of a large and growing proportion of individuals in Western society may represent such a pre-disease state and explain the explosive development of chronic diseases such as inflammatory bowel disease, obesity, and other inflammatory diseases. These diseases themselves represent other alternative stable states again and are therefore hard to cure. The holistic view of the microbiota-host association where feedback loops between microbiota and host are thought to maintain the system in a stable state-be it a healthy, pre-disease, or disease state-implies that integrated approaches, addressing host processes and microbiota, should be used to treat or prevent (pre-)disease

TLR ligands and butyrate increase Pyy expression through two distinct but inter-regulated pathways

The intestinal epithelium is an active barrier separating the host from its microbiota. It senses microbial compounds through expression of a wide range of receptors including the Toll-like receptors (TLRs). TLRs have been shown to regulate epithelium permeability or secretion of defensin by Paneth cells. However, the expression and function of TLRs in enteroendocrine L-cells, a specific subtype of intestinal cells secreting PYY and GLP-1, have not yet been assessed. PYY and GLP-1 are implicated in regulation of gut motility, food intake and insulin secretion, and are of great interest regarding obesity and type 2 diabetes. Using a cellular model of human L-cells and a reporter system for NF-kappa B activation pathway, we reported functional expression of TLRs in these cells. Stimulation with specific TLR-agonists increased expression of Pyy but not Proglucagon in an NF-kappa B-dependent manner. Moreover, the effect of TLR stimulation was additive to butyrate, a product of bacterial fermentation, on Pyy expression. Additionally, butyrate also increased Tlr expression, including Tlr4, and the NF-kappa B response to TLR stimulation. Altogether, our results demonstrated a role of TLRs in the modulation of Pyy expression and the importance of butyrate, a product of bacterial fermentation in regulation of microbial TLR-dependent sensing

Butyrate stimulates cyclin D and p21 and inhibits cyclin-dependent kinase 2 expression in HT-29 colonic epithelial cells

International audienc

Monocyte activity in the presence of calcium phosphate activated by 1,25 (OH)2 VD3 and interferon-gamma

International audienc

Les acides gras à chaîne courte : de la production colique aux effets physiologiques gastro-intestinaux

National audienc

Treatment of rat proximal and distal colonic cells with sodium orthovanadate enhances their adhesion and survival in primary culture

International audienc