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1.
Nutrients ; 12(8)2020 Aug 12.
Article in English | MEDLINE | ID: mdl-32806561

ABSTRACT

Although diet is an important factor influencing gut microbiota, there are very few studies regarding that relationship in Japanese people. Here, we analyzed the relationship between habitual dietary intake surveyed by food frequency questionnaire and the quantitative features of gut bacteria by quantitative PCR and next generation sequencer in 354 healthy Japanese adults. The α-diversity of gut microbiota was positively correlated with the intake of mushrooms and beans and negatively correlated with the intake of grains. The ß-diversity was significantly associated with the intake of fruits, mushrooms, seaweeds, seafoods, and alcoholic beverages. Multiple linear regression analysis of the relationship between food groups associated with the diversity of gut microbiota and the number of gut bacteria at the genus level found 24 significant associations, including a positive association between alcoholic beverages and the number of Fusobacterium. These results support that habitual dietary intake influenced the diversity of gut microbiota and was strongly associated with the number of specific gut bacteria. These results will help us to understand the complex relationship between habitual diet and gut microbiota of the Japanese.


Subject(s)
Colony Count, Microbial/statistics & numerical data , Diet/statistics & numerical data , Eating/physiology , Feeding Behavior/physiology , Gastrointestinal Microbiome/physiology , Adult , Agaricales , Diet/methods , Diet Surveys , Edible Grain , Fabaceae , Female , Healthy Volunteers , High-Throughput Nucleotide Sequencing , Humans , Japan , Linear Models , Male , Middle Aged , Real-Time Polymerase Chain Reaction , Young Adult
2.
Nat Microbiol ; 5(1): 34-39, 2020 01.
Article in English | MEDLINE | ID: mdl-31819216

ABSTRACT

The gut commensal segmented filamentous bacterium (SFB) attaches to the ileal epithelium and potently stimulates the host immune system. Using transmission electron microscopy (TEM), we show that mouse and rat SFB are flagellated above the concave tip at the unicellular intracellular offspring (IO) stage and that flagellation occurs prior to full IO differentiation and release of IOs from SFB filaments. This finding adds a missing link to the SFB life cycle.


Subject(s)
Bacteria, Anaerobic/growth & development , Bacteria, Anaerobic/ultrastructure , Flagella/ultrastructure , Animals , Cell Line , Flagella/metabolism , Flagellin/genetics , Flagellin/metabolism , Gene Expression Regulation, Bacterial , Humans , Ileum/microbiology , Intestinal Mucosa/microbiology , Mice , Rats , Toll-Like Receptor 5/metabolism
3.
Immunity ; 44(3): 634-646, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26982365

ABSTRACT

Physical separation between the mammalian immune system and commensal bacteria is necessary to limit chronic inflammation. However, selective species of commensal bacteria can reside within intestinal lymphoid tissues of healthy mammals. Here, we demonstrate that lymphoid-tissue-resident commensal bacteria (LRC) colonized murine dendritic cells and modulated their cytokine production. In germ-free and antibiotic-treated mice, LRCs colonized intestinal lymphoid tissues and induced multiple members of the IL-10 cytokine family, including dendritic-cell-derived IL-10 and group 3 innate lymphoid cell (ILC3)-derived IL-22. Notably, IL-10 limited the development of pro-inflammatory Th17 cell responses, and IL-22 production enhanced LRC colonization in the steady state. Furthermore, LRC colonization protected mice from lethal intestinal damage in an IL-10-IL-10R-dependent manner. Collectively, our data reveal a unique host-commensal-bacteria dialog whereby selective subsets of commensal bacteria interact with dendritic cells to facilitate tissue-specific responses that are mutually beneficial for both the host and the microbe.


Subject(s)
Bordetella Infections/immunology , Bordetella/immunology , Dendritic Cells/immunology , Interleukin-10/metabolism , Intestines/immunology , Lymphoid Tissue/immunology , Th17 Cells/immunology , Animals , Cells, Cultured , Cytokines/metabolism , Dendritic Cells/microbiology , Interleukin-10/genetics , Interleukins/genetics , Interleukins/metabolism , Intestines/microbiology , Lymphoid Tissue/microbiology , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Microbiota , Receptors, Interleukin-10/genetics , Receptors, Interleukin-10/metabolism , Symbiosis/genetics , Th17 Cells/microbiology , Interleukin-22
4.
Cell ; 163(2): 367-80, 2015 Oct 08.
Article in English | MEDLINE | ID: mdl-26411289

ABSTRACT

Intestinal Th17 cells are induced and accumulate in response to colonization with a subgroup of intestinal microbes such as segmented filamentous bacteria (SFB) and certain extracellular pathogens. Here, we show that adhesion of microbes to intestinal epithelial cells (ECs) is a critical cue for Th17 induction. Upon monocolonization of germ-free mice or rats with SFB indigenous to mice (M-SFB) or rats (R-SFB), M-SFB and R-SFB showed host-specific adhesion to small intestinal ECs, accompanied by host-specific induction of Th17 cells. Citrobacter rodentium and Escherichia coli O157 triggered similar Th17 responses, whereas adhesion-defective mutants of these microbes failed to do so. Moreover, a mixture of 20 bacterial strains, which were selected and isolated from fecal samples of a patient with ulcerative colitis on the basis of their ability to cause a robust induction of Th17 cells in the mouse colon, also exhibited EC-adhesive characteristics.


Subject(s)
Bacterial Adhesion , Citrobacter rodentium/physiology , Enterobacteriaceae Infections/immunology , Escherichia coli Infections/immunology , Escherichia coli O157/physiology , Intestinal Mucosa/immunology , Th17 Cells/immunology , Animals , Bacterial Infections/immunology , Epithelial Cells/immunology , Epithelial Cells/microbiology , Epithelial Cells/ultrastructure , Feces/microbiology , Humans , Immunoglobulin A/immunology , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Mice , Mice, Inbred C57BL , Mice, Inbred Strains , Microscopy, Electron, Scanning , Rats , Rats, Inbred F344 , Species Specificity
5.
J Biosci Bioeng ; 112(5): 451-7, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21862400

ABSTRACT

Bifidobacteria are beneficial to human health, but the mechanism remains unknown. We employed oligonucleotide microarrays to identify the Bifidobacterium breve strain Yakult (BbrY) genes up-regulated specifically in mouse intestine. Based on BbrY transcriptional responses in germ-free mice and in fecal cultures, k-means clustering picked up 93 genes that were up-regulated in the mouse intestine and thereafter Venn analysis to exclude genes that were up-regulated in both the mouse intestine and the fecal culture classified 45 genes as up-regulated specifically in the mouse intestine. Most of those genes are involved in sugar transport or sugar liberation, although the functions of several genes are unknown. Most of these genes are clustered on the BbrY genome and appear to be organized into operons. Expressions of several genes were further investigated by real time PCR, revealing that their expression profiles were identical in the mouse cecum and colon. The up-regulation of genes involved in sugar liberalization and uptake suggests that BbrY could possibly maintain energy homeostasis inside the mouse intestine, which contains low quantities of readily fermentable sugars.


Subject(s)
Bifidobacterium/genetics , Cecum/microbiology , Colon/microbiology , Feces/microbiology , Gene Expression Profiling , Probiotics/administration & dosage , Animals , Bifidobacterium/classification , Bifidobacterium/physiology , Female , Germ-Free Life , Humans , Intestinal Mucosa/microbiology , Mice , Mice, Inbred BALB C , Oligonucleotide Array Sequence Analysis , Real-Time Polymerase Chain Reaction , Symbiosis , Up-Regulation
6.
Science ; 331(6015): 337-41, 2011 Jan 21.
Article in English | MEDLINE | ID: mdl-21205640

ABSTRACT

CD4(+) T regulatory cells (T(regs)), which express the Foxp3 transcription factor, play a critical role in the maintenance of immune homeostasis. Here, we show that in mice, T(regs) were most abundant in the colonic mucosa. The spore-forming component of indigenous intestinal microbiota, particularly clusters IV and XIVa of the genus Clostridium, promoted T(reg) cell accumulation. Colonization of mice by a defined mix of Clostridium strains provided an environment rich in transforming growth factor-ß and affected Foxp3(+) T(reg) number and function in the colon. Oral inoculation of Clostridium during the early life of conventionally reared mice resulted in resistance to colitis and systemic immunoglobulin E responses in adult mice, suggesting a new therapeutic approach to autoimmunity and allergy.


Subject(s)
Clostridium/immunology , Colon/immunology , Colon/microbiology , Intestinal Mucosa/immunology , T-Lymphocytes, Regulatory/immunology , Animals , Anti-Bacterial Agents/pharmacology , Cecum/microbiology , Cells, Cultured , Clostridium/growth & development , Colitis/immunology , Colitis/pathology , Colitis/prevention & control , Colon/metabolism , Feces/microbiology , Forkhead Transcription Factors/metabolism , Germ-Free Life , Immunity, Innate , Immunoglobulin E/biosynthesis , Interleukin-10/immunology , Interleukin-10/metabolism , Intestinal Mucosa/metabolism , Intestine, Small/immunology , Metagenome , Mice , Mice, Inbred A , Mice, Inbred BALB C , Receptors, Pattern Recognition/physiology , Specific Pathogen-Free Organisms , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Regulatory/metabolism , Transforming Growth Factor beta/metabolism
7.
Immunity ; 32(6): 815-27, 2010 Jun 25.
Article in English | MEDLINE | ID: mdl-20620945

ABSTRACT

Commensal microbes can have a substantial impact on autoimmune disorders, but the underlying molecular and cellular mechanisms remain largely unexplored. We report that autoimmune arthritis was strongly attenuated in the K/BxN mouse model under germ-free (GF) conditions, accompanied by reductions in serum autoantibody titers, splenic autoantibody-secreting cells, germinal centers, and the splenic T helper 17 (Th17) cell population. Neutralization of interleukin-17 prevented arthritis development in specific-pathogen-free K/BxN mice resulting from a direct effect of this cytokine on B cells to inhibit germinal center formation. The systemic deficiencies of the GF animals reflected a loss of Th17 cells from the small intestinal lamina propria. Introduction of a single gut-residing species, segmented filamentous bacteria, into GF animals reinstated the lamina propria Th17 cell compartment and production of autoantibodies, and arthritis rapidly ensued. Thus, a single commensal microbe, via its ability to promote a specific Th cell subset, can drive an autoimmune disease.


Subject(s)
Arthritis, Rheumatoid/immunology , Bacteria/immunology , Interleukin-17/immunology , Intestines/microbiology , T-Lymphocytes, Helper-Inducer/immunology , Animals , Arthritis, Experimental/immunology , Arthritis, Experimental/microbiology , Arthritis, Rheumatoid/microbiology , Cell Separation , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Mice , Reverse Transcriptase Polymerase Chain Reaction
8.
Cell ; 139(3): 485-98, 2009 Oct 30.
Article in English | MEDLINE | ID: mdl-19836068

ABSTRACT

The gastrointestinal tract of mammals is inhabited by hundreds of distinct species of commensal microorganisms that exist in a mutualistic relationship with the host. How commensal microbiota influence the host immune system is poorly understood. We show here that colonization of the small intestine of mice with a single commensal microbe, segmented filamentous bacterium (SFB), is sufficient to induce the appearance of CD4(+) T helper cells that produce IL-17 and IL-22 (Th17 cells) in the lamina propria. SFB adhere tightly to the surface of epithelial cells in the terminal ileum of mice with Th17 cells but are absent from mice that have few Th17 cells. Colonization with SFB was correlated with increased expression of genes associated with inflammation and antimicrobial defenses and resulted in enhanced resistance to the intestinal pathogen Citrobacter rodentium. Thus, manipulation of this commensal-regulated pathway may provide new opportunities for enhancing mucosal immunity and treating autoimmune disease.


Subject(s)
Gram-Positive Bacteria/immunology , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , T-Lymphocytes, Helper-Inducer/immunology , Animals , Cell Differentiation , Citrobacter rodentium/immunology , Gram-Positive Bacteria/physiology , Immunity, Mucosal/immunology , Interleukin-17/immunology , Interleukins/immunology , Intestinal Mucosa/physiology , Mice , Mice, Inbred C57BL , Mucous Membrane/immunology , Mucous Membrane/microbiology , Serum Amyloid A Protein/metabolism , Specific Pathogen-Free Organisms , Symbiosis , Interleukin-22
9.
Nature ; 455(7214): 808-12, 2008 Oct 09.
Article in English | MEDLINE | ID: mdl-18716618

ABSTRACT

Interleukin (IL)-17-producing CD4(+) T lymphocytes (T(H)17 cells) constitute a subset of T-helper cells involved in host defence and several immune disorders. An intriguing feature of T(H)17 cells is their selective and constitutive presence in the intestinal lamina propria. Here we show that adenosine 5'-triphosphate (ATP) that can be derived from commensal bacteria activates a unique subset of lamina propria cells, CD70(high)CD11c(low) cells, leading to the differentiation of T(H)17 cells. Germ-free mice exhibit much lower concentrations of luminal ATP, accompanied by fewer lamina propria T(H)17 cells, compared to specific-pathogen-free mice. Systemic or rectal administration of ATP into these germ-free mice results in a marked increase in the number of lamina propria T(H)17 cells. A CD70(high)CD11c(low) subset of the lamina propria cells expresses T(H)17-prone molecules, such as IL-6, IL-23p19 and transforming-growth-factor-beta-activating integrin-alphaV and -beta8, in response to ATP stimulation, and preferentially induces T(H)17 differentiation of co-cultured naive CD4(+) T cells. The critical role of ATP is further underscored by the observation that administration of ATP exacerbates a T-cell-mediated colitis model with enhanced T(H)17 differentiation. These observations highlight the importance of commensal bacteria and ATP for T(H)17 differentiation in health and disease, and offer an explanation of why T(H)17 cells specifically present in the intestinal lamina propria.


Subject(s)
Adenosine Triphosphate/pharmacology , Cell Differentiation/drug effects , Mucous Membrane/cytology , Mucous Membrane/drug effects , T-Lymphocytes, Helper-Inducer/cytology , T-Lymphocytes, Helper-Inducer/drug effects , Adenosine Triphosphate/metabolism , Animals , CD11c Antigen/metabolism , CD27 Ligand/metabolism , Cells, Cultured , Colitis/chemically induced , Colitis/immunology , Colitis/pathology , Disease Models, Animal , Feces/microbiology , Female , Germ-Free Life , Immunoglobulin A/analysis , Immunoglobulin A/immunology , Interleukin-17/genetics , Interleukin-17/immunology , Interleukin-17/metabolism , Male , Mice , Mucous Membrane/immunology , Mucous Membrane/microbiology , Receptors, Purinergic P2/metabolism , T-Lymphocytes, Helper-Inducer/immunology
10.
World J Gastroenterol ; 14(16): 2511-6, 2008 Apr 28.
Article in English | MEDLINE | ID: mdl-18442197

ABSTRACT

AIM: To determine the anti-inflammatory activity of probiotic Bifidobacteria in Bifidobacteria-fermented milk (BFM) which is effective against active ulcerative colitis (UC) and exacerbations of UC, and to explore the immunoregulatory mechanisms. METHODS: Peripheral blood mononuclear cells (PBMNC) from UC patients or HT-29 cells were co-cultured with heat-killed probiotic bacteria or culture supernatant of Bifidobacterium breve strain Yakult (BbrY) or Bifidobacterium bifidum strain Yakult (BbiY) to estimate the amount of IL-10 or IL-8 secreted. RESULTS: Both strains of probiotic Bifidobacteria contained in the BFM induced IL-10 production in PBMNC from UC patients, though BbrY was more effective than BbiY. Conditioned medium (CM) and DNA of both strains inhibited IL-8 secretion in HT-29 cells stimulated with TNF-alpha, whereas no such effect was observed with heat-killed bacteria. The inhibitory effect of CM derived from BbiY was greater than that of CM derived from BbrY. DNAs of the two strains had a comparable inhibitory activity against the secretion of IL-8. CM of BbiY induced a repression of IL-8 gene expression with a higher expression of IkappaB-zeta mRNA 4 h after culture of HT-29 cells compared to that in the absence of CM. CONCLUSION: Probiotic Bifidobacterium strains in BFM enhance IL-10 production in PBMNC and inhibit IL-8 secretion in intestinal epithelial cells, suggesting that BFM has anti-inflammatory effects against ulcerative colitis.


Subject(s)
Bifidobacterium/physiology , Colitis, Ulcerative/immunology , HT29 Cells/physiology , Interleukin-10/biosynthesis , Interleukin-8/antagonists & inhibitors , Leukocytes, Mononuclear/physiology , Probiotics , Cell Culture Techniques , Culture Media, Conditioned , Cytokines/metabolism , DNA, Bacterial/metabolism , Humans , Interleukin-8/metabolism , Leukocytes, Mononuclear/microbiology , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha/pharmacology
11.
FEMS Immunol Med Microbiol ; 52(1): 69-77, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17995961

ABSTRACT

Probiotics are used for the improvement of gut disorders. To explore the potential of probiotics, a gnotobiotic study using BALB/c mice to analyze epithelial gene expression was performed. Microarray analysis of probiotic strain-monoassociated mice showed that Lactobacillus casei Shirota and Bifidobacterium breve Yakult noticeably affected gene expression in the ileal and colonic epithelial cells, respectively, although to a smaller extent than segmented filamentous bacteria (SFB). Lactobacillus casei Shirota enhanced the gene expression involving defense/immune functions and lipid metabolism more strongly than B. breve Yakult. In the colon, expression of a chloride transporter was slightly enhanced, although downregulation of many genes, such as guanine nucleotide-binding protein, was evident in mice with B. breve Yakult compared with the ones with L. casei Shirota. SFB affected gene expression more strongly than the probiotic strains. In particular, alpha(1-2) fucosyltransferase and pancreatitis-associated protein were significantly enhanced only in SFB-monoassociated mice but not probiotic strain-monoassociated mice. Gene expression of SFB-monoassociated mice was either stimulated or repressed in a manner similar to or opposite that of conventional colonized mice. Taken together, probiotic strains of L. casei Shirota and B. breve Yakult differentially affect epithelial gene expression in the small intestine and colon, respectively.


Subject(s)
Bifidobacterium/physiology , Gene Expression Regulation , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Lacticaseibacillus casei/physiology , Probiotics , Animals , Colon/immunology , Colon/metabolism , Colon/microbiology , Colony Count, Microbial , Gene Expression Profiling , Ileum/immunology , Ileum/metabolism , Ileum/microbiology , Intestinal Mucosa/immunology , Lipid Metabolism/genetics , Mice , Mice, Inbred BALB C , Oligonucleotide Array Sequence Analysis , Pancreatitis-Associated Proteins
12.
FEMS Microbiol Lett ; 215(2): 229-36, 2002 Oct 08.
Article in English | MEDLINE | ID: mdl-12399039

ABSTRACT

We found frequent IS1 integration nearby the stx(2) gene during in vitro mutagenesis of an stx(2) variant, stx(2vhd). To examine the possibility that such insertions have been contributing to generate new stx(2) variants, we screened 86 strains of Escherichia coli O157:H7 isolated in Japan for variations in the ca. 4-kb region flanking the stx(2) locus using PCR methods. Two major classes were identified based on the PCR amplicon size. DNA sequence analysis revealed that the stx(2) subtype of the two classes were stx(2) (referred to as stx(2-EDL933)) and stx(2vhd). IS1203v insertions were found in three stx(2vhd)-positive strains and two stx(2-EDL933)-positive strains, and no other insertions were found. These results suggest that the DNA sequences surrounding the stx(2) genes are preferably integrated by IS1203v in wild-type Shiga toxin-producing E. coli strains.


Subject(s)
DNA Transposable Elements/genetics , Escherichia coli O157/genetics , Genetic Variation , Shiga Toxin 2/genetics , Shiga Toxin/biosynthesis , Blotting, Southern , Escherichia coli Infections/virology , Humans , Mutagenesis, Site-Directed , Polymerase Chain Reaction , Sequence Analysis, DNA , Shiga Toxin 2/chemistry
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