Cephalosporinases associated with outer membrane vesicles released by Bacteroides spp. Our aim was to understand how the dominant human gut bacterium Neuronal cell populations, as well as enteroendocrine cells, were assessed in proximal colonic sections using fluorescent immunohistochemistry in specific pathogen-free (SPF), germ-free (GF) and Bt conventionalized-germ-free mice (Bt-CONV).
Bacteria; Bacteroidetes; Bacteroidetes (class); Bacteroidales; Bacteroidaceae (2) Immunol. Res. In healthy individuals, Bt OMVs stimulated significant (Overall, our findings suggest a key role for OMVs generated by the commensal gut bacterium Bt in directing a balanced immune response to constituents of the microbiota locally and systemically during health which is altered in IBD patients.The human gastrointestinal (GI) tract contains an estimated 3.8 × 10The production of OMVs by pathogenic gram-negative bacteria including Most of our understanding of OMVs-host interactions comes from animal model systems with the human immune response to Bt and OMVs being poorly characterised. Adv. Therefore, we have examined how DC from healthy individuals respond to Bt OMVs and how these responses change in individuals with inflammatory bowel disease (IBD)IL-10 is an immunoregulatory cytokine and is essential for intestinal homeostasis as demonstrated in mice lacking either IL-10 or IL-10 receptor genes that spontaneously develop inflammatory disease [DC are key antigen-presenting cells that both produce and respond to IL-10 to regulate immune responses [During normal anaerobic growth, Bt cells produce and release OMVs into the external milieu which consists of nanostructures exhibiting a typical spherical lipid bilayer (Fig.
L.H. PBMC were resuspended in complete medium (Dutch modified RPMI 1640 (Sigma-Aldrich, Dorset, UK) containing 100 U/mL penicillin/streptomycin, 2 mM Following incubation, PBMC and LP cells were washed with PBS and viability was determined by labelling cells with LIVE/DEAD™ Fixable Near-IR Dead Cell Stain Kit (Thermo Fisher Scientific) according to the manufacturer’s instructions. CD and UC are characterised by a loss of mucosal barrier integrity, leading to translocation of bacteria and triggering of inappropriate immune responses. Gram-negative Bacteroides thetaiotaomicron (Bt) is a prominent member of the intestinal microbiota of many animals [4,5,6]. 2016;65:256–70.Larsen JM, et al. mRNA expression levels in toll-like receptor 1 (TLR1-f), toll-like receptor 2 (TLR2-g), toll-like receptor 4 (TLR1-h), toll-like receptor 5 (TLR5-i) and toll-like receptor 9 (TLR9-j) in SPF, GF and Bt-CONV. No primary antibody controls were performed alongside each experiment to confirm the specificity of the primary antibody, which resulted in no fluorescence above background.Villi length (distance from the base of the crypt to the top of the villi) was measured using the ruler tool on Image J. Clin. 3.3) (Berezow et al., 2009).The contribution of the enteric microbiome to health and disease is a burgeoning area of investigation. Structure, function and diversity of the healthy human microbiome. RNA expression of tight junction protein claudin 3 was downregulated while TLR2 was upregulated by Bt-CONV. Nat. gut bacterium, Bacteroides thetaiotaomicron. You can also search for this author in 2016;2:22–39.e5.Mann ER, et al. Previous studies have shown a number of TLRs, including TLR2 are expressed in the mouse colon,This initial report describing the effects of Bt on ENS structure and function has limitations that arise from access, cost and feasibility of studying germ-free and mono-colonized mice. The colonic myenteric plexus tightly regulates functions such as motility that responds to the luminal environment, via neuronally mediated pathways.
was in receipt of an MRC Intermediate Research Fellowship (grant number MR/L01632X/1, UK Med-Bio).Régis Stentz and Alistair Noble contributed equally to this work.Antigen Presentation Research Group, Imperial College London, Northwick Park & St. Mark’s Hospital Campus, Watford Rd, Harrow, Greater London, HA1 3UJ, UKLydia Durant, Alistair Noble, Durga Reddi, Matthew J. O’Connor, E. Tobias Pring, Stella Dilke, Philip Hendy & Stella C. KnightGut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, NR4 7UQ, UKRégis Stentz, Johanne Brooks, Nadezhda Gicheva & Simon R. CardingNorwich Medical School, University of East Anglia, Norwich, NR4 7TJ, UKDepartment of Biosciences, Nottingham Trent University, Clifton Campus, Nottingham, NG11 8NS, UKFood Microbial Sciences Unit, University of Reading, Whiteknights, Reading, RG6 6UR, UKSt Mark’s Hospital, London North West University Healthcare NHS Trust, Harrow, Greater London, HA1 3UJ, UKRipple Man, E. Tobias Pring, Stella Dilke, Philip Hendy, Jonathan P. Segal, Dennis N. F. Lim, Ravi Misra, Ailsa L. Hart, Naila Arebi & Stella C. KnightYou can also search for this author in Bowel Dis. Cell Host Microbe. 2011;106:1544–55.de Smedt T, et al. Raw traces showing manometric pressure recordings in the whole colon in SPF (a), GF (b) and Bt-CONV (c). (2020). Comparative transcriptional and functional profiling defines conserved programs of intestinal DC differentiation in humans and mice.
All cytokines/chemokines were detectable apart from IFN-α2 which was below detection limits.PBMC were cultured with Bt or Bt OMVs as described above and cell supernatants were taken at 20 h post-stimulation and stored at −80 °C. Gastroenterol. Glial cell marker S100β (red) is significantly decreased in GF conditions in the mucosa compared to SPF (e and f) and Bt restores GAP43-IR to SPF levels.