Altered mucosal homeostasis in mice lacking secretory antibodies
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Leonardo Meza-Zepeda
PROVIDER: E-GEOD-34630 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:The mammalian gut is inhabited by a large and complex microbial community that lives in a mutualistic relationship with its host. Innate and adaptive mucosal defense mechanisms ensure a homeostatic relationship with this commensal microbiota. Secretory antibodies are generated from the active polymeric Ig receptor (pIgR)-mediated transport of IgA and IgM antibodies to the gut lumen and form the first line of adaptive immune defense of the intestinal mucosa. We probed mucosal homeostasis in pIgR knockout (KO) mice, which lack secretory antibodies. We found that in pIgR KO mice, colonic epithelial cells, the cell type most closely in contact with intestinal microbes, differentially expressed (>2-fold change) more than 200 genes compared with wild type mice, and upregulated the expression of anti-microbial peptides in a commensal-dependent manner. Detailed profiling of microbial communities based on 16S rRNA genes revealed differences in the commensal microbiota between pIgR KO and wild type mice. Furthermore, we found that pIgR KO mice showed increased susceptibility to dextran sulfate sodium (DSS)-induced colitis, and that this was driven by their conventional intestinal microbiota. In conclusion, secretory antibodies or the pIgR itself are required to maintain a stable commensal microbiota. In the absence of these humoral effector components, gut homeostasis is disturbed and the outcome of colitis significantly worsened.
2013-12-28 | GSE34630 | GEO
Project description:Inappropriate cross talk between mammals and their gut microbiota may trigger intestinal inflammation and drive extra-intestinal immune-mediated diseases. Studies with germ-free or gnotobiotic animals represent the gold standard for research on bacterial-host interaction but they are not readily accessible to the wide scientific community. We aimed at refining a protocol that in a robust manner would deplete murine intestinal microbiota and prove to have significant biologic validity. Previously published protocols for depleting mice of their intestinal microbiota by administering broad-spectrum antibiotics in drinking water were difficult to reproduce. We show that twice daily delivery of antibiotics by gavage depleted mice of their cultivable fecal microbiota and reduced the fecal bacterial DNA load by approximately 400 fold while ensuring the animals’ health. Mice subjected to the protocol for 17 days displayed enlarged ceca, reduced Peyer’s patches and small spleens. Antibiotic treatment significantly reduced the expression of antimicrobial factors and altered the expression of 517 genes in total in the colonic epithelium. Genes involved in cell cycle were significantly altered concomitant with reduced epithelial proliferative activity in situ assessed by Ki-67 expression, suggesting that commensal microbiota drives cellular proliferation in colonic epithelium. We present a robust protocol for depleting mice of their cultivatable intestinal microbiota with antibiotics by gavage and show that the biological effect of this depletion is phenotypic characteristics and epithelial gene expression profile similar to those of germ-free mice. Comparison of genome-wide gene expression of colon intestinal epithelial cells from mice subjected to microbiota depletion protocol against to control mice.
2011-08-14 | E-GEOD-22648 | biostudies-arrayexpress
Project description:The indigenous human gut microbiota is a major contributor to the human superorganism with established roles in modulating nutritional status, immunity, and systemic health including diabetes and obesity. The complexity of the gut microbiota consisting of over 1012 residents and approximately 1000 species has thus far eluded systematic analyses of the precise effects of individual microbial residents on human health. In contrast, health benefits have been shown upon ingestion of certain so-called probiotic Lactobacillus strains in food products and nutritional supplements, thereby providing a unique opportunity to study the global responses of a gut-adapted microorganism in the human gut and to identify the molecular mechanisms underlying microbial modulation of intestinal physiology, which might involve alterations in the intestinal physico-chemical environment, modifications in the gut microbiota, and/or direct interaction with mucosal epithelia and immune cells. Here we show by transcriptome analysis using DNA microarrays that the established probiotic bacterium, L. plantarum 299v, adapts its metabolic capacity in the human digestive tract for carbohydrate acquisition and expression of exo-polysaccharide and proteinaceous cell surface compounds. This report constitutes the first application of global gene expression profiling of a gut-adapted commensal microorganism in the human gut. Comparisons of the transcript profiles to those obtained for L. plantarum WCFS1 in germ-free mice revealed conserved L. plantarum responses indicative of a core transcriptome expressed in the mammalian gut and provide new molecular targets for determining microbial-host interactions affecting human health. Hybridization of the samples against a common reference of gDNA isolated from L. plantarum 299v
2010-05-16 | E-GEOD-17634 | biostudies-arrayexpress
Project description:Systemic infection induces conserved physiological responses that include both resistance and ‘tolerance of infection’ mechanisms. Among these responses, temporary anorexia associated with an infection is often beneficial. It poses, however, a problem for the trillions of microbes residing in the gastrointestinal tract, as they also experience reduced substrate availability. We hypothesized that under anorectic conditions caused by infection, the host might activate protective mechanisms to support the gut microbiota during the acute phase of the disease. Here, we report that systemic exposure to Toll-like receptor (TLR) ligands causes rapid α1,2-fucosylation of the small intestine epithelial cells (IEC). The process requires sensing of TLR agonists and production of IL-23 by dendritic cells, activation of innate lymphoid cells and expression of α1,2-Fucosyltransferase-2 (Fut2) by IL-22-stimulated IECs. Fucosylated proteins are shed into the lumen and fucose is utilized by microbiota, as shown using reporter bacteria and by transcriptional profiling of the gut microbiome. Fucosylation also reduces the expression of bacterial virulence genes within the commensal gut microbiome and improves host tolerance of the mild pathogen Citrobacter rodentium. Thus, rapid IEC fucosylation appears to be a protective mechanism that utilizes the host’s resources to maintain host-microbial interactions during pathogen-induced stress. RNA-Seq analysis of the murine gut microbiome following LPS exposure. Fut2-/- (B6.129X1-Fut2tm1Sdo/J) mice were backcrossed greater than 7 generations to BALB/c. Fut2-/- (KO) and Fut2+/- (Het) animals were analyzed.
2014-10-24 | E-GEOD-60874 | biostudies-arrayexpress
Project description:Abstract. Background: The cause of ulcerative colitis (UC) is not yet fully understood. Previous research has pointed towards a potential role for mutations in NOD2 in promoting the onset and progression of inflammatory bowel disease (IBD) by altering the microbiota of the gut. However, the relationship between toll-like receptor 4 (TLR4) and gut microbiota in IBD is not well understood. To shed light on this, the interaction between TLR4 and gut microbiota was studied using a mouse model of IBD. Methods: To examine the function of TLR4 signaling in intestinal injury repair, researchers developed Dextran Sulfate Sodium Salt (DSS)-induced colitis and injury models in both wild-type (WT) mice and TLR4 knockout (TLR4-KO) mice. To assess changes in the gut microbiota, 16S rRNA sequencing was conducted on fecal samples from both the TLR4-KO and WT enteritis mouse models. Results: The data obtained depicted a protective function of TLR4 against DSS-induced colitis. The gut microbiota composition was found to vary considerably between the WT and TLR4-KO mice groups as indicated by β-diversity analysis and operational taxonomic units (OTUs) cluster. Statistical analysis of microbial multivariate variables depicted an elevated abundance of Escherichia coli/Shigella, Gammaproteobacteria, Tenerlcutes, Deferribacteres, Enterobacteria, Rikenellaceae, and Proteobacteria in the gut microbiota of TLR4-KO mice, whereas there was a considerable reduction in Bacteroidetes at five different levels of the phylogenetic hierarchy including phylum, class, order, family, and genus in comparison with the WT control. Conclusion: TLR4 may protect intestinal epithelial cells from damage in response to DSS-induced injury by controlling the microbiota in the gut.
2023-11-01 | GSE227565 | GEO
Project description:The indigenous human gut microbiota is a major contributor to the human superorganism with established roles in modulating nutritional status, immunity, and systemic health including diabetes and obesity. The complexity of the gut microbiota consisting of over 1012 residents and approximately 1000 species has thus far eluded systematic analyses of the precise effects of individual microbial residents on human health. In contrast, health benefits have been shown upon ingestion of certain so-called probiotic Lactobacillus strains in food products and nutritional supplements, thereby providing a unique opportunity to study the global responses of a gut-adapted microorganism in the human gut and to identify the molecular mechanisms underlying microbial modulation of intestinal physiology, which might involve alterations in the intestinal physico-chemical environment, modifications in the gut microbiota, and/or direct interaction with mucosal epithelia and immune cells. Here we show by transcriptome analysis using DNA microarrays that the established probiotic bacterium, L. plantarum 299v, adapts its metabolic capacity in the human digestive tract for carbohydrate acquisition and expression of exo-polysaccharide and proteinaceous cell surface compounds. This report constitutes the first application of global gene expression profiling of a gut-adapted commensal microorganism in the human gut. Comparisons of the transcript profiles to those obtained for L. plantarum WCFS1 in germ-free mice revealed conserved L. plantarum responses indicative of a core transcriptome expressed in the mammalian gut and provide new molecular targets for determining microbial-host interactions affecting human health.
2010-01-01 | GSE17634 | GEO
Project description:We generate B-cell-specific Tlr9-deficient (Tlr9fl/fl/Cd19Cre+/-, KO) B6 mice and model obesity using a high-fat diet. Compared with control mice, B cell Tlr9-deficient mice exhibited increased weight gain, impaired glucose and insulin tolerance, reduced IL-10-producing B cells and increased inflammation in fat tissues. Tlr9 deficiency affected B cell differentiation, immunoglobulin levels, and T cell subsets. Furthermore, altered gut microbiota in B-cell-specific Tlr9-deficient mice led to a pro-inflammatory status in gut associated lymphoid tissues and glucose metabolism dysregulation. Using 16S rRNA sequencing we report altered gut microbial communities in the KO mice. Indeed, a reduction in Lachnospiraceae, may play a key role in the observed metabolic phenotypes in KO mice. Also, We identify an important network involving Tlr9, Irf4 and Il-10.
2024-04-11 | GSE263396 | GEO
Project description:Auricularia auricula is a well-known traditional edible and medicinal fungus with high nutritional and pharmacological values, as well as metabolic and immunoregulatory properties. However, the exact mechanisms underlying the effects of Auricularia auricula polysaccharides (AAP) on obesity and related metabolic endpoints, including the role of the gut microbiota, remain insufficiently understood. To determine the mechanistic role of the gut microbiota in observed anti-obesogenic effects AAP, faecal microbiota transplantation (FMT) and pseudo germ-free mice model treated with antibiotics were also applied, together with 16S rRNA genomic-derived taxonomic profiling. HFD murine exposure to AAP thwarted weight-gains, reduced fat depositing, together with upregulating thermogenesis proteomic biomarkers within adipose tissue. These effects were associated with diminished intestine/bloodstream-borne lipid transportation, together with enhanced glucose tolerance. FMT administered in tandem with antibiotic treatment demonstrated the intestinal microbiota was necessary in deploying AAP anti-obesogenic functions. Intestine-dwelling microbial population assessments discovered AAP to enhance (in a selective manner) Papillibacter cinnamivorans, a commensal bacterium having reduced presence within HFD mice. Notably, HFD mice treated with oral formulations of Papillibacter cinnamivorans diminished obesity and was linked to decreased intestinal lipid transportation. Datasets from the present study show that AAP thwarted dietary-driven obesity and metabolism-based disorders through regulating intestinal lipid transportation, a mechanism that is dependent on the gut commensal Papillibacter cinnamivorans. These results indicated AAP and Papillibacter cinnamivorans as newly identified pre- and probiotics that could possibly serve as novel countermeasure against obesity.
2022-05-03 | GSE201951 | GEO
Project description:Auricularia auricula is a well-known traditional edible and medicinal fungus with high nutritional and pharmacological values, as well as metabolic and immunoregulatory properties. However, the exact mechanisms underlying the effects of Auricularia auricula polysaccharides (AAP) on obesity and related metabolic endpoints, including the role of the gut microbiota, remain insufficiently understood. To determine the mechanistic role of the gut microbiota in observed anti-obesogenic effects AAP, faecal microbiota transplantation (FMT) and pseudo germ-free mice model treated with antibiotics were also applied, together with 16S rRNA genomic-derived taxonomic profiling. HFD murine exposure to AAP thwarted weight-gains, reduced fat depositing, together with upregulating thermogenesis proteomic biomarkers within adipose tissue. These effects were associated with diminished intestine/bloodstream-borne lipid transportation, together with enhanced glucose tolerance. FMT administered in tandem with antibiotic treatment demonstrated the intestinal microbiota was necessary in deploying AAP anti-obesogenic functions. Intestine-dwelling microbial population assessments discovered AAP to enhance (in a selective manner) Papillibacter cinnamivorans, a commensal bacterium having reduced presence within HFD mice. Notably, HFD mice treated with oral formulations of Papillibacter cinnamivorans diminished obesity and was linked to decreased intestinal lipid transportation. Datasets from the present study show that AAP thwarted dietary-driven obesity and metabolism-based disorders through regulating intestinal lipid transportation, a mechanism that is dependent on the gut commensal Papillibacter cinnamivorans. These results indicated AAP and Papillibacter cinnamivorans as newly identified pre- and probiotics that could possibly serve as novel countermeasure against obesity.
2022-05-03 | GSE201950 | GEO
Project description:Maintenance of intestinal homeostasis requires a healthy relationship between the commensal gut microbiota and the host immune system. Breast milk supplies the first source of antigen-specific immune protection in the gastrointestinal tract of suckling mammals, in the form of secretory immunoglobulin A (SIgA). SIgA is transported across glandular and mucosal epithelial cells into external secretions by the polymeric immunoglobulin receptor (pIgR). Here, a breeding scheme with pIgR-sufficient and -deficient mice was used to study the effects of breast milk-derived SIgA on development of the gut microbiota and host intestinal immunity. Early exposure to maternal SIgA prevented the translocation of aerobic bacteria from the neonatal gut into draining lymph nodes, including the opportunistic pathogen Ochrobactrum anthropi. By the age of weaning, mice that received maternal SIgA in breast milk had a significantly different gut microbiota from mice that did not receive SIgA, and these differences were magnified when the mice reached adulthood. Early exposure to SIgA in breast milk resulted in a pattern of intestinal epithelial cell gene expression in adult mice that differed from that of mice that were not exposed to passive SIgA, including genes associated with intestinal inflammatory diseases in humans. Maternal SIgA was also found to ameliorate colonic damage caused by the epithelial-disrupting agent dextran sulfate sodium. These findings reveal unique mechanisms through which SIgA in breast milk may promote lifelong intestinal homeostasis, and provide additional evidence for the benefits of breastfeeding. We used microarrays to determine the effects of passive and active secretory IgA, in the presence or absence of the epithelial-disrupting agent dextran sulfate sodium, on gene expression in intestinal epithelial cells of mice A breeding scheme was used that involved crosses between mouse dams and sires that were deficient or sufficient for expression of the polymeric immunoglobulin receptor (Pigr), a protein that is required for transport of secretory IgA (SIgA) into external secretions. Offspring of these crosses were genotyped for Pigr alleles, and littermate offspring were distributed into 4 groups based on early exposure to passive SIgA in mother's milk (P-yes and P-no) and ability to carry out Pigr-mediated endogenous transport of active SIgA (A-yes and A-no). Seventy-day-old gender-matched Pigr+/- and Pigr-/- offspring of Pigr+/- and Pigr-/- dams were left untreated or given 2% dextran sulfate sodium (DSS) in drinking water for 8 days. Colonic epithelial cells were isolated, and total cellular RNA was purified. RNA was pooled from 3 mice for each of 2 biological replicates for microarray analysis.
2014-01-25 | E-GEOD-54371 | biostudies-arrayexpress