Project description:The gut microbiota is essential for many aspects of host physiology, and locally generated secretory IgA (SIgA) modulates its function. Microbiota community determines the efficacy of immune checkpoint blockade (ICB) in cancer immunotherapy. Extracellular ATP (eATP) released by the microbiota restricts the SIgA repertoire by limiting T follicular helper (Tfh) cells activity in the Peyer’s Patches (PPs) via stimulation of ionotropic P2X7 receptor. Here we show that SIgA amplification by oral administration of the ATP hydrolysing enzyme apyrase corrects enteropathic features of ICB and improves the therapeutic outcome.
Project description:The gut microbiota is essential for many aspects of host physiology, and locally generated secretory IgA (SIgA) modulates its function. Microbiota community determines the efficacy of immune checkpoint blockade (ICB) in cancer immunotherapy. Extracellular ATP (eATP) released by the microbiota restricts the SIgA repertoire by limiting T follicular helper (Tfh) cells activity in the Peyer’s Patches (PPs) via stimulation of ionotropic P2X7 receptor. Here we show that SIgA amplification by oral administration of the ATP hydrolysing enzyme apyrase corrects enteropathic features of ICB and improves the therapeutic outcome.
Project description:Loss of immune tolerance to the gut microbiome plays a pathogenic role in inflammatory bowel disease (IBD). How dietary factors alter host immune-gut microbiome interactions in IBD is unclear. Here, we apply multi-omics (IgA-SEQ, IgG-SEQ, blood scRNA-seq and immune repertoire sequencing) to investigate the effects of 12 weeks of vitamin D on host immune microbe interactions in patients with IBD. Vitamin D treatment associates with decreased disease activity and inflammatory markers and increased IgA-bound and decreased IgG-bound gut microbiota. Vitamin D alters the profiles of IgA-bound (increased Lachnospiraceae, Blautia) and IgG-bound (decreased Proteobacteria, Enterococcaceae) gut bacteria. Vitamin D increases BAFF signaling between plasmacytoid dendritic cells and B cells, alters BCR and TCR clonotypes that associate with Ig-bound gut microbiota, and increases α4β7+ B and T regulatory cells. Our results demonstrate that vitamin D promotes immune tolerance to gut microbiota in patients with IBD. Clinical trial is registered under NCT04828031
Project description:Loss of immune tolerance to the gut microbiome plays a pathogenic role in inflammatory bowel disease (IBD). How dietary factors alter host immune-gut microbiome interactions in IBD is unclear. Here, we apply multi-omics (IgA-SEQ, IgG-SEQ, blood scRNA-seq and immune repertoire sequencing) to investigate the effects of 12 weeks of vitamin D on host immune microbe interactions in patients with IBD. Vitamin D treatment associates with decreased disease activity and inflammatory markers and increased IgA-bound and decreased IgG-bound gut microbiota. Vitamin D alters the profiles of IgA-bound (increased Lachnospiraceae, Blautia) and IgG-bound (decreased Proteobacteria, Enterococcaceae) gut bacteria. Vitamin D increases BAFF signaling between plasmacytoid dendritic cells and B cells, alters BCR and TCR clonotypes that associate with Ig-bound gut microbiota, and increases α4β7+ B and T regulatory cells. Our results demonstrate that vitamin D promotes immune tolerance to gut microbiota in patients with IBD. Clinical trial is registered under NCT04828031
Project description:Loss of immune tolerance to the gut microbiome plays a pathogenic role in inflammatory bowel disease (IBD). How dietary factors alter host immune-gut microbiome interactions in IBD is unclear. Here, we apply multi-omics (IgA-SEQ, IgG-SEQ, blood scRNA-seq and immune repertoire sequencing) to investigate the effects of 12 weeks of vitamin D on host immune microbe interactions in patients with IBD. Vitamin D treatment associates with decreased disease activity and inflammatory markers and increased IgA-bound and decreased IgG-bound gut microbiota. Vitamin D alters the profiles of IgA-bound (increased Lachnospiraceae, Blautia) and IgG-bound (decreased Proteobacteria, Enterococcaceae) gut bacteria. Vitamin D increases BAFF signaling between plasmacytoid dendritic cells and B cells, alters BCR and TCR clonotypes that associate with Ig-bound gut microbiota, and increases α4β7+ B and T regulatory cells. Our results demonstrate that vitamin D promotes immune tolerance to gut microbiota in patients with IBD. Clinical trial is registered under NCT04828031
Project description:In the presented study, in order to unravel gut microbial community multiplicity and the influence of maternal milk nutrients (i.e., IgA) on gut mucosal microbiota onset and shaping, a mouse GM (MGM) was used as newborn study model to discuss genetic background and feeding modulation on gut microbiota in term of symbiosis, dysbiosis and rebiosis maintenance during early gut microbiota onset and programming after birth. Particularly, a bottom-up shotgun metaproteomic approach, combined with a computational pipeline, has been compred with a culturomics analysis of mouse gut microbiota, obtained by MALDI-TOF mass spectrometry (MS).
Project description:Our preliminary data suggest that differential gut microbiota modulates acetaminophen-induced hepatotoxicity (APAP toxicity) in mice model. The goal of our study is to determine whether commensal gut microbiota modulates the hepatic gene expressions potentially responsible for modulating APAP toxicity.
Project description:Colorectal cancer is a leading cause of cancer-related deaths. Mutations in the innate immune receptor AIM2 are frequently identified in patients with colorectal cancer, but how AIM2 modulates colonic tumorigenesis is unknown. Here, we found that Aim2-deficient mice were hypersusceptible to colonic tumor development. Production of inflammasome-associated cytokines and other inflammatory mediators were largely intact in Aim2-deficient mice, however, intestinal stem cells were prone to uncontrolled proliferation. Aberrant Wnt signaling expanded a population of tumor-initiating stem cells in the absence of AIM2. Susceptibility of Aim2-deficient mice to colorectal tumorigenesis was enhanced by a dysbiotic gut microbiota, which was reduced by reciprocal exchange of gut microbiota with wild-type healthy mice. These findings uncover a synergy between a specific host genetic factor and gut microbiota in determining the susceptibility to colorectal cancer. Therapeutic modulation of AIM2 expression and microbiota has the potential to prevent colorectal cancer. We used microarrays to compare the transcriptome Aim2 deficent mice to wild type mice in colon tumor and colitis samples. Here were 12 mice in total, 3 for each genotype and tissue combination.
Project description:Nutritional supplementation is emerging as a promising strategy to support the clinical management of early Alzheimer’s disease (AD), partly through modulation of the intestinal microbiome via the microbiota–gut–brain axis. This study investigated the impact of Fortasyn Connect (Souvenaid®), a multinutrient formulation, on the gut microbiota using a dual approach: i) a dynamic gastrointestinal simulator (simgi®) inoculated with fecal samples from AD patients, and ii) an observational study involving early-stage AD patients (n = 22) receiving or not the supplement. The in vitro model provided a host-independent assessment of microbiota responses, revealing increased Bifidobacterium and Lactobacillus levels, along with enhanced short-chain fatty acid (SCFA) production. In patients, supplementation was associated with higher fecal abundance of Bifidobacterium and Christensenellaceae, reduced inflammatory markers (calprotectin and myeloperoxidase), and elevated butyrate levels. Fecal lipidomic and proteomic analyses indicated improved lipid digestion, increased secretory IgA, and modulation of host proteins related to gut–brain homeostasis. Systemically, higher circulating levels of iron, folate, and vitamin B12 were also observed. This study demonstrates that multinutrient supplementation such as Fortasyn Connect can beneficially modulate the gut ecosystem and immune–metabolic pathways in early AD, targeting disease-relevant mechanisms through the gut–brain axis in the context of aging.