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Zhao J, Pan J, Zhang Z, Chen Z, Mai K, Zhang Y. Fishmeal Protein Replacement by Defatted and Full-Fat Black Soldier Fly Larvae Meal in Juvenile Turbot Diet: Effects on the Growth Performance and Intestinal Microbiota. AQUACULTURE NUTRITION 2023; 2023:8128141. [PMID: 37089257 PMCID: PMC10115534 DOI: 10.1155/2023/8128141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/07/2023] [Accepted: 02/27/2023] [Indexed: 05/03/2023]
Abstract
A 12-week feeding trial was conducted to investigate the effect of the same fishmeal protein level replaced by black soldier fly larvae (Hermetia illucens) meal (BSFL) with different lipid contents on the growth performance and intestinal health of juvenile turbot (Scophthalmus maximus L.) (initial body weight 12.64 g). Three isonitrogenous and isolipidic diets were formulated: fish meal-based diet (FM), diets DF and FF, in which 14% fish meal protein of the FM diet was replaced by defatted and full-fat BSFL, respectively. There were no significant differences in growth performance, intestinal morphology, and mucosal barrier function between the DF and the FM group. However, diet FF markedly reduced the growth performance, intestinal perimeter ratio, and the gene expression of anti-inflammatory cytokine TGF-β (P < 0.05). Compared to group FF, the communities of intestinal microbiota in group DF were more similar to group FM. Moreover, diet DF decreased the abundance of some potential pathogenic bacteria and enriched the potential probiotics, such as Bacillus. Diet FF obviously altered the composition of intestinal microbiota and increased the abundance of some potential pathogenic bacteria. These results suggested that the application of defatted BSFL showed more positive effects on fish growth and intestinal health than the full-fat BSFL, and the intestinal microbiota was closely involved in these effects.
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Affiliation(s)
- Jingjing Zhao
- Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Jintao Pan
- Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Zhonghao Zhang
- Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Zhichu Chen
- Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Kangsen Mai
- Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
- Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao 266237, China
| | - Yanjiao Zhang
- Key Laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture, The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
- Qingdao National Laboratory for Marine Science and Technology, 1 Wenhai Road, Qingdao 266237, China
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Grześkowiak Ł, Martínez-Vallespín B, Zentek J, Vahjen W. A Preliminary Survey of the Distribution of Segmented Filamentous Bacteria in the Porcine Gastrointestinal Tract. Curr Microbiol 2021; 78:3757-3761. [PMID: 34476557 PMCID: PMC8435515 DOI: 10.1007/s00284-021-02636-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 08/18/2021] [Indexed: 11/30/2022]
Abstract
Segmented filamentous bacteria (SFB) are present in various animal species including pigs. The aim of this work was to analyze the occurrence of SFB in different parts of the gastrointestinal tract of piglets of different ages. A total of 377 DNA extracts from stomach, jejunum, ileum, cecum and colon digesta, and from feces collected on different time points, originating from 155 animals, were screened by qPCR method with primers specific for the SFB. SFB sequences were detected in 74 of 377 samples (19.6%) from 155 animals in total. SFB were most abundant in ileum (50.0%), cecum (45.0%), and colon (37.0%), followed by feces (14.6%). SFB prevalence in sows was 12.9% (13/101) and 75.9% (41/54) in individual piglets. Of the 41 SFB-positive piglets, only two samples were from pre-weaning animals, while the rest of samples originated from post-weaning piglets. SFB sequences are abundant in post-weaning piglets, but not in suckling or adult animals. They are most abundant in the ileum and cecum of pigs. Further studies are warranted to reveal the role of SFB in pigs.
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Affiliation(s)
- Łukasz Grześkowiak
- Institute of Animal Nutrition, Freie Universität Berlin, Berlin, Germany.
| | | | - Jürgen Zentek
- Institute of Animal Nutrition, Freie Universität Berlin, Berlin, Germany
| | - Wilfried Vahjen
- Institute of Animal Nutrition, Freie Universität Berlin, Berlin, Germany
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Wolfe AE, Moskowitz JE, Franklin CL, Wiemken TL, Ericsson AC. Interactions of Segmented Filamentous Bacteria (Candidatus Savagella) and bacterial drivers in colitis-associated colorectal cancer development. PLoS One 2020; 15:e0236595. [PMID: 32706816 PMCID: PMC7380633 DOI: 10.1371/journal.pone.0236595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/08/2020] [Indexed: 01/19/2023] Open
Abstract
Colorectal cancer (CRC) risk is influenced by host genetics, sex, and the gut microbiota. Using a genetically susceptible mouse model of CRC induced via inoculation with pathobiont Helicobacter spp. and demonstrating variable tumor incidence, we tested the ability of the Th17-enhancing commensal Candidatus Savagella, more commonly denoted as Segmented Filamentous Bacteria (SFB), to influence the incidence and severity of colitis-associated CRC in male and female mice. To document the composition of the gut microbiota during CRC development and identify taxa associated with disease, fecal samples were collected before and throughout disease development and characterized via 16S rRNA sequencing. While there were no significant SFB-dependent effects on disease incidence or severity, SFB was found to exert a sex-dependent protective effect in male mice. Furthermore, SFB stabilized the GM against Helicobacter-induced changes post-inoculation, resulting in a shift in disease association from Helicobacter spp. to Escherichia coli. These data support sex-dependent SFB-mediated effects on CRC risk, and highlight the complex community dynamics within the GM during exposure to inflammatory pathobionts.
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Affiliation(s)
- Annie E. Wolfe
- Molecular Pathogenesis and Therapeutics, University of Missouri, Columbia, Missouri, United States of America
| | - Jacob E. Moskowitz
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
| | - Craig L. Franklin
- Molecular Pathogenesis and Therapeutics, University of Missouri, Columbia, Missouri, United States of America
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
- University of Missouri Metagenomics Center, Columbia, Missouri, United States of America
- University of Missouri Mutant Mouse Resource and Research Center, Columbia, Missouri, United States of America
- University of Missouri College of Veterinary Medicine, Columbia, Missouri, United States of America
| | - Timothy L. Wiemken
- Saint Louis University Center for Health Outcomes Research, St. Louis, Missouri, United States of America
| | - Aaron C. Ericsson
- Molecular Pathogenesis and Therapeutics, University of Missouri, Columbia, Missouri, United States of America
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
- University of Missouri Metagenomics Center, Columbia, Missouri, United States of America
- University of Missouri Mutant Mouse Resource and Research Center, Columbia, Missouri, United States of America
- University of Missouri College of Veterinary Medicine, Columbia, Missouri, United States of America
- * E-mail:
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Chen H, Wang L, Wang X, Wang X, Liu H, Yin Y. Distribution and Strain Diversity of Immunoregulating Segmented Filamentous Bacteria in Human Intestinal Lavage Samples. MICROBIAL ECOLOGY 2020; 79:1021-1033. [PMID: 31728601 DOI: 10.1007/s00248-019-01441-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 09/11/2019] [Indexed: 06/10/2023]
Abstract
Segmented filamentous bacteria (SFB) are well known for their functions in the immunoregulation of hosts including the promotion of Th17 cell differentiation, B cell maturation, and immune system development. However, most analyses of SFB have focused on animal models, and thus, investigation of SFB prevalence in humans and their roles in human immunoregulation and health is needed. Although little is known overall of SFB prevalence in humans, they are characteristically abundant in animals during weaning. In this study, SFB-like bacteria were detected in ileal lavage samples from human children that were aged between 1 to 17 years old by scanning electron microscopy (SEM) analysis, and their insertion into the mucosa was also observed. In addition, the expression of SFB flagellin at the human bacterial interface was observed by immunohistochemistry (IHC) and western blot. Moreover, two pairs of primers specific for SFB, but targeting different genes, were used to detect SFB in human intestinal lavage samples. These analyses indicated that SFB were present in over 50% of patient ileal samples independent of age. High-throughput gene sequencing indicated that different SFB strains were detected among samples. Between nine and 23 SFB flagellin gene operational taxonomic units were identified. In addition to evaluating the prevalence of SFB in human samples, correlations between SFB presence and chief complaints of clinical symptoms were evaluated, as well as the relationship between SFB and patient serum immunoglobulin concentrations. SFB prevalence was significantly higher in hematochezia patients (68%) than in abdominal pain (56.10%) and diarrhea (43.75%) patients. Furthermore, the concentrations of serum IgA, IgM, and IgE, were similar between SFB-positive and SFB-negative patient groups, although IgG concentrations were significantly higher in the SFB-negative group.
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Affiliation(s)
- Huahai Chen
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou, Hunan, China
- State Key Laboratory of Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Zhejiang, Hangzhou, China
| | - Ling Wang
- Children's Hospital of Shanghai, Children's Hospital of Shanghai Jiaotong University, Shanghai, China
| | - Xing Wang
- Children's Hospital of Shanghai, Children's Hospital of Shanghai Jiaotong University, Shanghai, China
| | - Xin Wang
- State Key Laboratory of Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Zhejiang, Hangzhou, China.
| | - Haifeng Liu
- Children's Hospital of Shanghai, Children's Hospital of Shanghai Jiaotong University, Shanghai, China.
| | - Yeshi Yin
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou, Hunan, China.
- State Key Laboratory of Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Zhejiang, Hangzhou, China.
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Wang Y, Yin Y, Chen X, Zhao Y, Wu Y, Li Y, Wang X, Chen H, Xiang C. Induction of Intestinal Th17 Cells by Flagellins From Segmented Filamentous Bacteria. Front Immunol 2019; 10:2750. [PMID: 31824516 PMCID: PMC6883716 DOI: 10.3389/fimmu.2019.02750] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 11/11/2019] [Indexed: 12/18/2022] Open
Abstract
T-helper-17 (Th17) cells are a subset of CD4+ T cells that can produce the cytokine interleukin (IL)-17 and play vital roles in protecting the host from bacterial and fungal infections, especially at the mucosal surface. These are abundant in the small intestinal lamina propria (SILP) and their differentiation are associated with the colonization of the intestinal flora. Segmented filamentous bacteria (SFB) drew the attention of researchers due to their unique ability to drive the accumulation of Th17 cells in the SI LP of mice. Recent work has highlighted that SFB used microbial adhesion-triggered endocytosis (MATE) to transfer SFB antigenic proteins into small intestinal epithelial cells (SI ECs) and modulate host immune homeostasis. However, which components of SFB are involved in this immune response process remains unclear. Here, we examined the roles of SFB flagellins in Th17 cells induction using various techniques, including ELISA, ELISPOT, and RNA-seq in vitro and in vivo. The results show that the immune function of SFB flagellins is similar to SFB, i.e., induces the appearance of CD4+ T helper cells that produce IL-17 and IL-22 (Th17 cells) in the SI LP. Furthermore, treatment of mice with SFB flagellins lead to a significant increase in the expression of genes associated with the IL-17 signaling pathway, such as IL-6, IL-1β, TNF-α, IL-17A, IL-17F, and IL-22. In addition, SFB flagellins have an intimate relationship with intestinal epithelial cells, influencing the expression of epithelial cell-specific genes such as Nos2, Duox2, Duoxa2, SAA3, Tat, and Lcn2. Thus, we propose that SFB flagellins play a significant role in the involvement of SFB in the induction of intestinal Th17 cells.
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Affiliation(s)
- Yanling Wang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yeshi Yin
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou, China
| | - Xin Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yongjia Zhao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yichen Wu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yifei Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Xin Wang
- State Key Laboratory of Breeding Base for Zhejiang Sustainable Pest and Key Laboratory for Food Microbial Technology of Zhejiang Province, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Huahai Chen
- Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, Yongzhou, China
| | - Charlie Xiang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
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Nowrouzian FL, Stadler LS, Adlerberth I, Wold AE. The 16S rRNA gene-based PCR method used for the detection of segmented filamentous bacteria in the intestinal microbiota generates false-positive results. APMIS 2018; 125:940-942. [PMID: 28929595 DOI: 10.1111/apm.12743] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Forough L Nowrouzian
- Department of Infectious Diseases, Institution of Biomedicine, Gothenburg University, Gothenburg, Sweden
| | - Liselott Svensson Stadler
- Department of Infectious Diseases, Institution of Biomedicine, Gothenburg University, Gothenburg, Sweden
| | - Ingegerd Adlerberth
- Department of Infectious Diseases, Institution of Biomedicine, Gothenburg University, Gothenburg, Sweden
| | - Agnes E Wold
- Department of Infectious Diseases, Institution of Biomedicine, Gothenburg University, Gothenburg, Sweden
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Finotti A, Gasparello J, Lampronti I, Cosenza LC, Maconi G, Matarese V, Gentili V, Di Luca D, Gambari R, Caselli M. PCR detection of segmented filamentous bacteria in the terminal ileum of patients with ulcerative colitis. BMJ Open Gastroenterol 2017; 4:e000172. [PMID: 29259792 PMCID: PMC5728270 DOI: 10.1136/bmjgast-2017-000172] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/31/2017] [Accepted: 11/17/2017] [Indexed: 02/07/2023] Open
Abstract
Objectives Segmented filamentous bacteria (SFB) have been detected in a wide range of different animal. Recently, the presence of SFB-like bacteria was shown in biopsies of the terminal ileum and ileocecal valve of both patients with ulcerative colitis and control subjects. The aim of this study was to verify whether PCR methods could be used for the detection of SFB in biopsy of patients with ulcerative colitis and its relationships with the disease stage. Methods PCR methods were used to identify SFB in biopsies from the terminal ileum of patients with ulcerative colitis, showing that this approach represents a useful tool for the detection of SFB presence and analysis of the bacterial load. Results Our analysis detected SFB in all faecal samples of children at the time of weaning, and also show that putative SFB sequences are present in both patients with ulcerative colitis and control subjects. Results obtained using real-time quantitative PCR analysis confirm the presence of putative SFB sequences in samples from the terminal ileum of patients with ulcerative colitis and in control subjects. Conclusions The presence of putative SFB sequence in both patients with ulcerative colitis and control subject suggests that SFB cannot be considered as being uniquely associated with the disease. The second conclusion is that among the patients with ulcerative colitis, a tendency does exist for active disease samples to show higher SFB load, opening new perspectives about possible identification and pharmacological manipulation of SFB-mediated processes for new therapeutic strategy.
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Affiliation(s)
- Alessia Finotti
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Jessica Gasparello
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Ilaria Lampronti
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Lucia Carmela Cosenza
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Giovanni Maconi
- Department of Gastroenterology, Sacco Hospital, University of Milan, Milan, Italy
| | | | - Valentina Gentili
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Dario Di Luca
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Roberto Gambari
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Michele Caselli
- School of Gastroenterology, University of Ferrara, Ferrara, Italy
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Stremmel W, Staffer S, Schneider MJ, Gan-Schreier H, Wannhoff A, Stuhrmann N, Gauss A, Wolburg H, Mahringer A, Swidsinski A, Efferth T. Genetic Mouse Models with Intestinal-Specific Tight Junction Deletion Resemble an Ulcerative Colitis Phenotype. J Crohns Colitis 2017; 11:1247-1257. [PMID: 28575164 PMCID: PMC5881657 DOI: 10.1093/ecco-jcc/jjx075] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 05/23/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS A key pathogenetic feature of ulcerative colitis [UC] is an intrinsic low mucus phosphatidylcholine[PC] content. Recently, a paracellular transport for PC across tight junctions[TJs] was described, suggesting TJ disturbance as a cause of diminished luminal PC transport. Therefore, we aimed to generate mutant mice with TJ deletion to evaluate whether a UC phenotype developed. METHODS CL57BL/6 control wild-type mice were compared to mutant mice with tamoxifen-induced villin-Cre-dependent intestinal deletion of kindlin 1 and 2. RESULTS Electron microscopy of mucosal biopsies obtained from both mutants before overt inflammation following only 2 days of tamoxifen exposure revealed a defective TJ morphology with extended paracellular space and, by light microscopy, expanded mucosal crypt lumina. PC secretion into mucus was reduced by >65% and the mucus PC content dropped by >50%, causing a >50 % decrease of mucus hydrophobicity in both mutants. Consequently, the microbiota was able to penetrate the submucosa. After 3 days of tamoxifen exposure, intestinal inflammation was present in both mutants, with loose bloody stools as well as macroscopic and histological features of colitis. Oral PC supplementation was able to suppress inflammation. By analogy, colonic biopsies obtained from patients with UC in remission also showed a defective epithelium with widened intercellular clefts, and enlarged crypt luminal diameters with functionally impaired luminal PC secretion. CONCLUSIONS Genetic mouse models with intestinal deletion of kindlin 1 and 2 resulted in TJ deletion and revealed pathophysiological features of impaired PC secretion to the mucus leading to mucosal inflammation compatible with human UC.
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Affiliation(s)
- Wolfgang Stremmel
- Department of Internal Medicine IV, University Clinics of Heidelberg, Heidelberg, Germany,Corresponding author: Wolfgang Stremmel, MD, PhD, Professor of Medicine, University Clinics of Heidelberg, Department of Internal Medicine IV, 69120 Heidelberg, Germany. Tel: +49 6221 56 8700;
| | - Simone Staffer
- Department of Internal Medicine IV, University Clinics of Heidelberg, Heidelberg, Germany
| | | | - Hongying Gan-Schreier
- Department of Internal Medicine IV, University Clinics of Heidelberg, Heidelberg, Germany
| | - Andreas Wannhoff
- Department of Internal Medicine IV, University Clinics of Heidelberg, Heidelberg, Germany
| | - Nicole Stuhrmann
- Department of Internal Medicine IV, University Clinics of Heidelberg, Heidelberg, Germany
| | - Annika Gauss
- Department of Internal Medicine IV, University Clinics of Heidelberg, Heidelberg, Germany
| | - Hartwig Wolburg
- Department of Pathology and Neuropathology, University Medical School of Tübingen, Tübingen, Germany
| | - Anne Mahringer
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University of Heidelberg, Heidelberg, Germany
| | - Alexander Swidsinski
- Department of Gastroenterology, University Hospital Charité of Berlin, 10115 Berlin, Germany
| | - Thomas Efferth
- Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, Mainz, Germany
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Host Specificity of Flagellins from Segmented Filamentous Bacteria Affects Their Patterns of Interaction with Mouse Ileal Mucosal Proteins. Appl Environ Microbiol 2017; 83:AEM.01061-17. [PMID: 28687648 DOI: 10.1128/aem.01061-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 06/26/2017] [Indexed: 11/20/2022] Open
Abstract
Segmented filamentous bacteria (SFB) are known modulators of the mammalian immune system. Currently, the technology for investigating SFB culture in vitro is immature, and as a result, the mechanisms of SFB colonization and immune regulation are not yet fully elucidated. In this study, we investigated the gene diversity and host specificity of SFB flagellin genes. The fliC1 and fliC2 genes are relatively conserved, while the fliC3 and fliC4 genes are more variable, especially at the central and C-terminal regions. Host specificity analysis demonstrated that the fliC1 genes do not cluster together based on the host organism, whereas the fliC3 and fliC4 genes were host specific at the nucleotide and deduced amino acid levels. SFB flagellin protein expression in the ileum mucosa and cecal contents was detected by using fluorescence in situ hybridization (FISH) combined with immunohistochemical (IHC) analysis, immunoblotting, and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Although the purified SFB FliC3 protein originating from both mouse and rat was able to activate Toll-like receptor 5 (TLR5)-linked NF-κB signaling, no host specificity was observed. Interestingly, the patterns of interaction with mouse ileum mucosal proteins were different for mouse FliC3 (mFliC3) and rat FliC3 (rFliC3). Gene Ontology (GO) and KEGG analyses indicated that more adherence-related proteins interacted with mFliC3, while more lysosome- and proteolysis-related proteins interacted with rFliC3. In vitro degradation experiments indicated that the stability of rFliC3 was lower than that of mFliC3 when they were incubated with mouse ileum mucosal proteins. In summary, the gene diversity and host specificity of SFB flagellin genes were investigated, and SFB flagellin expression was detected in gut samples.IMPORTANCE Since SFB genomes contain only one copy of each FliC gene, the diversity of FliC is representative of SFB strain diversity. Currently, little is known regarding the diversity and specificity of members of the group of SFB. The work presented herein demonstrates that select SFB strains, exhibiting unique FliC patterns, are present in a variety of mammalian hosts. SFB fliC genes were found to interact with a number of unique targets, providing further evidence for SFB host selection. Together, this work represents a major advancement in identifying SFB and delineating how members of the group of SFB interact with the host. Future examination of FliC genes will likely enhance our knowledge of intestinal colonization by the gut microbiota.
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Ramos LRV, Pedrosa VF, Mori A, Andrade CFFDE, Romano LA, Abreu PC, Tesser MB. Exogenous enzyme complex prevents intestinal soybean meal-induced enteritis in Mugil liza (Valenciennes, 1836) juvenile. AN ACAD BRAS CIENC 2017; 89:341-353. [PMID: 28198920 DOI: 10.1590/0001-3765201720160446] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 09/20/2016] [Indexed: 11/22/2022] Open
Abstract
Four soybean meal-based diets containing increasing levels of an enzyme complex (E50, E100, E150 and E200 at 50, 100, 150 and 200 g ton-1, respectively) and one soybean meal-based diet without the enzyme complex (E0) were fed in triplicate to M. liza juveniles in a semi-static flow system with 20 fish per tank for 75 days. There were no differences between the treatments for animal performance parameters, but fish fed the enzyme complex treatment exhibited significantly (P<0.05) higher values of calcium bone retention compared with control fish. Although there was no relationship between bacterial counts in different sections of the gastrointestinal tract or enzyme levels, filamentous bacteria were increased in E50 compared with E150. All of the treatments resulted in higher bacterial counts in the stomach than in intestinal segments. Histological screening showed serious to moderate infiltration of inflammatory cells, modification in villus morphology and necrosis in some cases in fish fed the E0 diet. In addition, fish from the E0 treatment exhibited significantly (P<0.05) lower lipid deposition in the peritoneal cavity. Therefore, the use of low levels of exogenous enzyme is recommended in diets for M. liza when soybean meal is used as the main source of protein.
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Affiliation(s)
- Leonardo R V Ramos
- Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande/FURG, Avenida Itália, Km 8, s/n, Bairro Carreiros, 96201-900 Rio Grande, RS, Brazil
| | - Virgínia F Pedrosa
- Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande/FURG, Avenida Itália, Km 8, s/n, Bairro Carreiros, 96201-900 Rio Grande, RS, Brazil
| | - Agnes Mori
- Adisseo Brasil Nutrição Animal, Avenida Maria Coelho Aguiar, 215, Bloco G, 1º andar, Jardim São Luis, 05804-900 São Paulo, SP, Brazil
| | - Carlos F F DE Andrade
- Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande/FURG, Avenida Itália, Km 8, s/n, Bairro Carreiros, 96201-900 Rio Grande, RS, Brazil
| | - Luis A Romano
- Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande/FURG, Avenida Itália, Km 8, s/n, Bairro Carreiros, 96201-900 Rio Grande, RS, Brazil
| | - Paulo C Abreu
- Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande/FURG, Avenida Itália, Km 8, s/n, Bairro Carreiros, 96201-900 Rio Grande, RS, Brazil
| | - Marcelo B Tesser
- Programa de Pós-Graduação em Aquicultura, Universidade Federal do Rio Grande/FURG, Avenida Itália, Km 8, s/n, Bairro Carreiros, 96201-900 Rio Grande, RS, Brazil
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McCarthy Ú, Pettinello R, Feehan L, Ho YM, White P. Experimental transmission of segmented filamentous bacteria (SFB) in rainbow trout Oncorhynchus mykiss. DISEASES OF AQUATIC ORGANISMS 2016; 119:45-57. [PMID: 27068502 DOI: 10.3354/dao02977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Rainbow trout gastroenteritis (RTGE) has been the cause of acute mortality in farmed rainbow trout in Europe since 1992. Epidemiological analysis has indicated a strong association with high production levels and suggested an infectious aetiology. The condition is characterised by the presence of large numbers of segmented filamentous bacteria (SFB) in the intestine, but the role of these in the disease has not been confirmed, in part because the organisms cannot be cultured. Therefore, other approaches need to be developed to investigate the role of SFB in RTGE. Faecal material from clinically affected RTGE trout, either untreated or heat-inactivated, was administered to fish from a susceptible stock, to determine whether the SFB could be transferred artificially and survive in or colonise the new host. Using histology and nested PCR, SFB were detected in the pyloric caeca of fish 23 to 30 d after challenge with untreated faeces. Histological changes in the intestine and the presence of an unidentified Gram-negative coccus were also significantly associated with exposure to untreated faeces. Upregulation of IFN-γ, IL-17A/F and IL-22 gene expression in proximal intestine suggested a low-level immune response to the challenge.
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Affiliation(s)
- Ú McCarthy
- Marine Scotland Science, Marine Laboratory, Aberdeen AB11 9DB, UK
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12
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Abstract
Endospore formation follows a complex, highly regulated developmental pathway that occurs in a broad range of Firmicutes. Although Bacillus subtilis has served as a powerful model system to study the morphological, biochemical, and genetic determinants of sporulation, fundamental aspects of the program remain mysterious for other genera. For example, it is entirely unknown how most lineages within the Firmicutes regulate entry into sporulation. Additionally, little is known about how the sporulation pathway has evolved novel spore forms and reproductive schemes. Here, we describe endospore and internal offspring development in diverse Firmicutes and outline progress in characterizing these programs. Moreover, comparative genomics studies are identifying highly conserved sporulation genes, and predictions of sporulation potential in new isolates and uncultured bacteria can be made from these data. One surprising outcome of these comparative studies is that core regulatory and some structural aspects of the program appear to be universally conserved. This suggests that a robust and sophisticated developmental framework was already in place in the last common ancestor of all extant Firmicutes that produce internal offspring or endospores. The study of sporulation in model systems beyond B. subtilis will continue to provide key information on the flexibility of the program and provide insights into how changes in this developmental course may confer advantages to cells in diverse environments.
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Tapia-Paniagua S, Lobo C, Moreno-Ventas X, de la Banda IG, Moriñigo MA, Balebona MC. Probiotic supplementation influences the diversity of the intestinal microbiota during early stages of farmed senegalese sole (Solea Senegalensis, Kaup 1858). MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2014; 16:716-728. [PMID: 25103323 DOI: 10.1007/s10126-014-9588-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 07/06/2014] [Indexed: 06/03/2023]
Abstract
Ingestion of bacteria at early stages results in establishment of a primary intestinal microbiota which likely undergoes several stages along fish life. The role of this intestinal microbiota regulating body functions is crucial for larval development. Probiotics have been proved to modulate this microbiota and exert antagonistic effects against fish pathogens. In the present study, we aimed to determine bacterial diversity along different developmental stages of farmed Senegalese sole (Solea senegalensis) after feeding probiotic (Shewanella putrefaciens Pdp11) supplemented diet for a short period (10-30 days after hatching, DAH). Intestinal lumen contents of sole larvae fed control and probiotic diets were collected at 23, 56, 87, and 119 DAH and DNA was amplified using 16S rDNA bacterial domain-specific primers. Amplicons obtained were separated by denaturing gradient gel electrophoresis (DGGE), cloned, and resulting sequences compared to sequences in GenBank. Results suggest that Shewanella putrefaciens Pdp11 induces a modulation of the dominant bacterial taxa of the intestinal microbiota from 23 DAH. DGGE patterns of larvae fed the probiotic diet showed a core of bands related to Lactobacillus helveticus, Pseudomonas acephalitica, Vibrio parahaemolyticus, and Shewanella genus, together with increased Vibrio genus presence. In addition, decreased number of clones related to Photobacterium damselae subsp piscicida at 23 and 56 DAH was observed in probiotic-fed larvae. A band corresponding to Shewanella putrefaciens Pdp11 was sequenced as predominant from 23 to 119 DAH samples, confirming the colonization by the probiotics. Microbiota modulation obtained via probiotics addition emerges as an effective tool to improve Solea senegalensis larviculture.
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Affiliation(s)
- Silvana Tapia-Paniagua
- Departamento de Microbiología, Universidad de Málaga, Campus de Teatinos s/n, 29071, Málaga, Spain
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14
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Caselli M, Cassol F, Gentili V, Di Luca D. Genome sequences of segmented filamentous bacteria in animals: implications for human research. Gut Microbes 2013; 3:401-5. [PMID: 22713269 DOI: 10.4161/gmic.20736] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Experimental studies indicate that segmented filamentous bacteria (SFB) can recapitulate fundamental immune responses, particularly in reference to Th 17 and regulatory T-cell activity. The recent description of whole genomic DNA sequences of mouse and rat SFBs and the comparison between these sequences opens new important perspectives. In particular this knowledge allows to perform quali-quantitative studies in human beings regarding these yet unculturable anaerobic bacteria. The comparative analysis of rat and mouse SFB 16S rRNA sequences suggests the existence of highly conserved regions that could represent SFB-specific molecular targets potentially useful to develop PCR probes for study SFB in humans. These molecular tools may be of inestimable value to evaluate the possible role played by SFB in the immune system physiology, as well as its potential involvement in human chronic inflammatory and autoimmune diseases.
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Affiliation(s)
- Michele Caselli
- School of Gastroenterology, Department of Experimental and Diagnostic Medicine, University of Ferrara, Ferrara, Italy
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15
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Yin Y, Wang Y, Zhu L, Liu W, Liao N, Jiang M, Zhu B, Yu HD, Xiang C, Wang X. Comparative analysis of the distribution of segmented filamentous bacteria in humans, mice and chickens. ISME JOURNAL 2012; 7:615-21. [PMID: 23151642 DOI: 10.1038/ismej.2012.128] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Segmented filamentous bacteria (SFB) are indigenous gut commensal bacteria. They are commonly detected in the gastrointestinal tracts of both vertebrates and invertebrates. Despite the significant role they have in the modulation of the development of host immune systems, little information exists regarding the presence of SFB in humans. The aim of this study was to investigate the distribution and diversity of SFB in humans and to determine their phylogenetic relationships with their hosts. Gut contents from 251 humans, 92 mice and 72 chickens were collected for bacterial genomic DNA extraction and subjected to SFB 16S rRNA-specific PCR detection. The results showed SFB colonization to be age-dependent in humans, with the majority of individuals colonized within the first 2 years of life, but this colonization disappeared by the age of 3 years. Results of 16S rRNA sequencing showed that multiple operational taxonomic units of SFB could exist in the same individuals. Cross-species comparison among human, mouse and chicken samples demonstrated that each host possessed an exclusive predominant SFB sequence. In summary, our results showed that SFB display host specificity, and SFB colonization, which occurs early in human life, declines in an age-dependent manner.
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Affiliation(s)
- Yeshi Yin
- State Key Laboratory of Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China
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16
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Cecchini F, Iacumin L, Fontanot M, Comi G, Manzano M. Identification of the unculturable bacteria Candidatus arthromitus in the intestinal content of trouts using Dot blot and Southern blot techniques. Vet Microbiol 2012; 156:389-94. [DOI: 10.1016/j.vetmic.2011.11.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2011] [Revised: 11/17/2011] [Accepted: 11/22/2011] [Indexed: 11/27/2022]
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17
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Liao N, Yin Y, Sun G, Xiang C, Liu D, Yu HD, Wang X. Colonization and distribution of segmented filamentous bacteria (SFB) in chicken gastrointestinal tract and their relationship with host immunity. FEMS Microbiol Ecol 2012; 81:395-406. [PMID: 22429007 DOI: 10.1111/j.1574-6941.2012.01362.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2011] [Revised: 03/03/2012] [Accepted: 03/06/2012] [Indexed: 11/30/2022] Open
Abstract
Uncultivable segmented filamentous bacteria (SFB) reside in the gastrointestinal (GI) tract of mammals and can boost the host immunity. Immunoglobulin A (IgA) from mother's milk has been previously shown to be a key factor in regulating SFB colonization. Because neonatal chicken cannot acquire IgA from maternal milk, they are a good model to examine the role of IgA in SFB colonization. Here, we used the fluorescent in situ hybridization (FISH) and quantitative PCR (qPCR) to monitor the colonization and distribution of SFB in chickens aged from 2-day-old to 6-week-old. Early SFB colonization, which primarily occurred in the ileal mucosa (< 13 days old), was IgA independent. From the age of 17-42 days, there was an increase in IgA in the gut mucosa, which was correlated with a decrease in SFB. To examine the effect of probiotics and immunosuppression on SFB colonization, we treated the chickens by feeding them Lactobacillus delbrueckii or giving them a subcutaneous injection of cyclophosphamide (CTX). Feeding lactobacilli at birth rendered SFB colonization occurring 4 days earlier, while CTX treatment increases the SFB colonization through reducing the other non-SFB bacteria. Altogether, our data suggest that early colonization of SFB in chicken occurs independently of IgA and the population of SFB in the GI tract of chicken may be manipulated from birth via probiotic or CTX treatment.
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Affiliation(s)
- Ningbo Liao
- State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
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18
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Thompson CL, Vier R, Mikaelyan A, Wienemann T, Brune A. 'Candidatus Arthromitus' revised: segmented filamentous bacteria in arthropod guts are members of Lachnospiraceae. Environ Microbiol 2012; 14:1454-65. [PMID: 22436008 DOI: 10.1111/j.1462-2920.2012.02731.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The name Arthromitus has been applied collectively to conspicuous filamentous bacteria found in the hindguts of termites and other arthropods. First observed by Joseph Leidy in 1849, the identity of these filaments has remained contentious. While Margulis and colleagues declared them to be a life stage of Bacillus cereus, others have assumed them to belong to the same lineage as the segmented filamentous bacteria (SFB) from vertebrate guts, a group that has garnered much attention due to their unique ability to specifically modulate their host's immune response. Both SFB and Arthromitus filaments from arthropod guts were grouped under provisional name 'Candidatus Arthromitus' by Snel and colleagues as they share a striking similarity in terms of their morphology and close contact to the host gut wall. While SFB form a distinct lineage within the family Clostridiaceae, the identity of the filaments from arthropod guts remains elusive. Using whole-genome amplification of single filaments capillary picked from termite guts and fluorescence in situ hybridization of 16S rRNA with group-specific oligonucleotide probes, we show that they represent a monophyletic lineage within the family Lachnospiraceae distinct from that of SFB. Therefore, 'Candidatus Arthromitus' can no longer be used for both groups. Given the historic precedence, we propose to reserve this name for the filaments that were originally described by Leidy. For the SFB from vertebrate guts, we propose the provisional name 'Candidatus Savagella' in honour of the American gut microbiologist Dwayne C. Savage, who was the first to describe that important bacterial group.
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Affiliation(s)
- Claire L Thompson
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg, Germany
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19
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Complete genome sequences of rat and mouse segmented filamentous bacteria, a potent inducer of th17 cell differentiation. Cell Host Microbe 2012; 10:273-84. [PMID: 21925114 DOI: 10.1016/j.chom.2011.08.007] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 08/04/2011] [Accepted: 08/17/2011] [Indexed: 12/12/2022]
Abstract
Segmented filamentous bacteria (SFB) are noncultivable commensals inhabiting the gut of various vertebrate species and have been shown to induce Th17 cells in mice. We present the complete genome sequences of both rat and mouse SFB isolated from SFB-monocolonized hosts. The rat and mouse SFB genomes each harbor a single circular chromosome of 1.52 and 1.59 Mb encoding 1346 and 1420 protein-coding genes, respectively. The overall nucleotide identity between the two genomes is 86%, and the substitution rate was estimated to be similar to that of the free-living E. coli. SFB genomes encode typical genes for anaerobic fermentation and spore and flagella formation, but lack most of the amino acid biosynthesis enzymes, reminiscent of pathogenic Clostridia, exhibiting large dependency on the host. However, SFB lack most of the clostridial virulence-related genes. Comparative analysis with clostridial genomes suggested possible mechanisms for host responses and specific adaptations in the intestine.
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20
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Ronza P, Bermúdez R, Losada AP, Robles A, Quiroga MI. Mucosal CD3ε+ cell proliferation and gut epithelial apoptosis: implications in rainbow trout gastroenteritis (RTGE). JOURNAL OF FISH DISEASES 2011; 34:433-443. [PMID: 21488908 DOI: 10.1111/j.1365-2761.2011.01254.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Rainbow trout gastroenteritis (RTGE) is an emerging disease that has acquired new relevance in European rainbow trout, Oncorhynchus mykiss (Walbaum), culture, because of the economic losses it causes. Disease aetiology and pathogenesis remain unclear. The lesions appear restricted to the gastrointestinal tract where extensive mucosal detachment associated with high numbers of segmented filamentous bacteria (SFB) can be detected. In this study, an RTGE outbreak in north-western Spain was investigated, and findings observed in diseased trout were compared with control fish. PAS stain and immunohistochemical assays with anti-CD3ε and anti-active caspase-3 antibodies were performed. The results showed that CD3ε+ inflammatory infiltrates were present in the intestine of diseased trout both in the lamina propria-submucosa and within the epithelium. Moreover, an increased number of caspase-3+ cells in the intestinal mucosa and also strong anti-caspase-3 immunoreactivity in desquamated cells in the gut lumen were observed. Changes in the number of goblet cells were also found, resulting in an increase or depletion of mucous cells depending on the severity of the intestinal lesions. These findings suggest that T cells and apoptosis play an important role in the development and pathogenesis of RTGE.
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Affiliation(s)
- P Ronza
- Departamento de Ciencias Clínicas Veterinaria, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo, Spain
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21
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McAleer JP, Kolls JK. Mechanisms controlling Th17 cytokine expression and host defense. J Leukoc Biol 2011; 90:263-70. [PMID: 21486905 DOI: 10.1189/jlb.0211099] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Th17 cells contribute to mucosal immunity by stimulating epithelial cells to induce antimicrobial peptides, granulopoiesis, neutrophil recruitment, and tissue repair. Recent studies have identified important roles for commensal microbiota and Ahr ligands in stabilizing Th17 gene expression in vivo, linking environmental cues to CD4 T cell polarization. Epigenetic changes that occur during the transition from naïve to effector Th17 cells increase the accessibility of il17a, il17f, and il22 loci to transcription factors. In addition, Th17 cells maintain the potential for expressing T-bet, Foxp3, or GATA-binding protein-3, explaining their plastic nature under various cytokine microenvironments. Although CD4 T cells are major sources of IL-17 and IL-22, innate cell populations, including γδ T cells, NK cells, and lymphoid tissue-inducer cells, are early sources of these cytokines during IL-23-driven responses. Epithelial cells and fibroblasts are important cellular targets for IL-17 in vivo; however, recent data suggest that macrophages and B cells are also stimulated directly by IL-17. Thus, Th17 cells interact with multiple populations to facilitate protection against intracellular and extracellular pathogens.
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Affiliation(s)
- Jeremy P McAleer
- Department of Genetics, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
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22
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Del-Pozo J, Crumlish M, Ferguson HW, Green DM, Turnbull JF. A prospective longitudinal study of “Candidatus arthromitus”-associated rainbow trout gastroenteritis in the UK. Prev Vet Med 2010; 94:289-300. [DOI: 10.1016/j.prevetmed.2010.02.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 01/29/2010] [Accepted: 02/06/2010] [Indexed: 11/16/2022]
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23
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Manzano M, Giusto C, Iacumin L, Patthey C, Cecchini F, Fontanillas R, Comi G. Nested PCR for the detection of Candidatus arthromitus in fish. FEMS Microbiol Lett 2010; 308:35-9. [PMID: 20455950 DOI: 10.1111/j.1574-6968.2010.01984.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Rainbow trout gastroenteritis has been related to the accumulation of segmented filamentous bacteria in the digestive tract of fish, which presents lethargy, reduced appetite and accumulation of mucoid faeces. Some authors associate the comparison of illness with the presence of viable filaments, which produce and release strings of endospores in the lumen of the gut. The segmented filamentous bacteria that could not be cultured in vitro have been related to Clostridium group I, and they have been named Candidatus arthromitus. Despite the various strategies that have been used to detect unculturable microorganisms, molecular methods have facilitated studies on culture-independent microorganisms. Direct DNA extraction from samples and subsequent study of 16S rRNA genes represent a tool for studying unculturable microbial flora. As direct detection of specific microorganisms is possible through the utilization of primers or probes annealing specific DNA sequences, the aim of this work was to design specific primers for the direct detection of C. arthromitus in fish using a nested PCR.
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Affiliation(s)
- Marisa Manzano
- Department of Food Science, University of Udine, Udine, Italy.
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24
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Yamamoto K, Qi WM, Yokoo Y, Miyata H, Udayanga KGS, Kawano J, Yokoyama T, Hoshi N, Kitagawa H. Lectin histochemical detection of special sugars on the mucosal surfaces of the rat alimentary tract. J Vet Med Sci 2010; 72:1119-27. [PMID: 20379083 DOI: 10.1292/jvms.10-0011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Surfaces of the most luminal positions of mucosae are fundamental settlement sites of indigenous bacteria throughout the rat alimentary tract. In these positions, also epithelial cell-shedding sites, the special sugar expression in the glycocalyx is very important as it provides possible ligands of bacterial lectins for attachment to epithelial cells. Therefore, the sugar expression in glycocalyx of epithelial cells was lectin-histochemically surveyed using 21 lectins throughout the rat alimentary tract. From the tongue to the nonglandular part of the stomach, α-D-Man, α-D-Glc and α-D-GalNAc were detected on the surface of the keratinized stratified squamous epithelium. In the glandular part of the stomach, α-D-Man, β-D-Gal-4GlcNAc, D-Gal, D-GalNAc, D-GlcNAc, α-L-Fuc- α-D-Gal-β(1-4)GlcNAc and bisected triantennary N-glycans were detected on the surface of gastric superficial epithelial cells. From the duodenum to the ileum, (GlcNAc)(2-4) was expressed exclusively on the epithelial cells in the apical portions of the intestinal villi. From the cecum to the rectum, α-D-Man, β-D-Gal-4GlcNAc, D-Gal, D-GalNAc, α-D-Gal(1-3)D-GalNAc, (GalNAc)(n) and NeuNAc were expressed on the intestinal superficial epithelial cells. These results suggest that special sugars are expressed on the most luminal portions of mucosae as exclusive epithelial cell-shedding sites, and that sugar expression differs among the various segments of the alimentary tract. These site differences might reflect differences in resident bacterial species in the rat alimentary tract.
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Affiliation(s)
- Kenkichi Yamamoto
- Department of Bioresource and Agrobiosciences Graduate School of Science and Technology, Kobe University, Kobe, Japan
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25
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Del-Pozo J, Turnbull JF, Crumlish M, Ferguson HW. A study of gross, histological and blood biochemical changes in rainbow trout, Oncorhynchus mykiss (Walbaum), with rainbow trout gastroenteritis (RTGE). JOURNAL OF FISH DISEASES 2010; 33:301-310. [PMID: 20059635 DOI: 10.1111/j.1365-2761.2009.01122.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The mechanisms behind the pathogenesis of rainbow trout gastroenteritis (RTGE) are still unknown. This study examined the macroscopic and microscopic changes in trout with RTGE (RTGE+), as well as the blood chemistry. A total of 464 rainbow trout were sampled from 11 sites in the UK, comprising 152 RTGE+ fish and 330 random, apparently healthy fish. A case definition for RTGE was assessed by the analysis of its agreement with three laboratory tests: histopathology, packed cell volume and kidney bacteriology. Cluster analysis indicated the presence of three distinct presentations within the population of RTGE+ fish. Cluster A included gross signs associated with moribund RTGE+ fish, and clusters B and C identified gross signs consistent with concurrent diseases, notably furunculosis, enteric redmouth and proliferative kidney disease. The information gained was used to select RTGE+ fish without concurrent disease for the analysis of RTGE pathogenesis with blood biochemistry. This analysis revealed a severe osmotic imbalance and a reduced albumin/globulin ratio as indicatives of selective loss of albumin. These findings are compatible with a protein losing enteropathy.
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Affiliation(s)
- J Del-Pozo
- Institute of Aquaculture, University of Stirling, Stirling, UK.
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26
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Del-Pozo J, Turnbull J, Ferguson H, Crumlish M. A comparative molecular study of the presence of "Candidatus arthromitus" in the digestive system of rainbow trout, Oncorhynchus mykiss (Walbaum), healthy and affected with rainbow trout gastroenteritis. JOURNAL OF FISH DISEASES 2010; 33:241-250. [PMID: 19912454 DOI: 10.1111/j.1365-2761.2009.01117.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Observations were made using histopathological techniques in conjunction with a nested polymerase chain reaction (PCR) protocol for the specific detection of "Candidatus arthromitus" on DNA extracted from wax-embedded tissues and fresh digestive contents of rainbow trout. Samples positive for "Candidatus arthromitus" DNA included fish with rainbow trout gastroenteritis (RTGE), clinically normal cohabiting fish, and apparently healthy controls from RTGE positive and RTGE negative sites. The results obtained from the PCR were confirmed by nucleotide sequencing. "Candidatus arthromitus" DNA was found in distal intestine as well as in sections of pyloric caeca, suggesting that both these locations are appropriate for molecular detection of "Candidatus arthromitus" DNA in trout. Furthermore, rainbow trout fry distal intestinal samples from two different hatcheries where RTGE had not been reported were also positive. Differences in "Candidatus arthromitus" DNA detection between paraffin wax-embedded and fresh digestive content samples from the same fish suggested that it may be predominantly epithelium-associated in healthy trout. Parallel histopathological observations indicated that pyloric caeca are the preferred site for visualizing segmented filamentous bacteria (SFB) in trout with RTGE. The results of this study showed that the presence of SFB was not invariably associated with clinical disease and that more information is required to understand the role of these organisms.
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Affiliation(s)
- J Del-Pozo
- Department of veterinary pathology, Easter Bush Veterinary Centre, Roslin, Midlothian, UK.
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27
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Del-Pozo J, Crumlish M, Turnbull JF, Ferguson HW. Histopathology and ultrastructure of segmented filamentous bacteria-associated rainbow trout gastroenteritis. Vet Pathol 2010; 47:220-30. [PMID: 20106826 DOI: 10.1177/0300985809359381] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Rainbow trout gastroenteritis (RTGE) is an emerging syndrome linked to the presence of large numbers of the segmented filamentous bacterium "Candidatus arthromitus" within the intestine. The present study examined the histopathological changes of the digestive tract of 152 trout with gross lesions typical of RTGE. Histopathology showed that 129 of 152 fish (85%) affected with RTGE had segmented filamentous bacteria in the distal intestine and/or pyloric caeca. The presence and number of segmented filamentous bacteria were always significantly higher (P < .001) in pyloric caeca, thereby suggesting the preferred site for these bacteria. Histopathological changes included enterocyte detachment and congestion of the lamina propria and adventitial layers. Samples from 6 RTGE-affected trout were examined using scanning and transmission electron microscopy, revealing a close interaction of segmented filamentous bacteria with the mucosa of distal intestine and pyloric caeca, with the presence of bacterial attachment sites, and with associated morphological changes of the apical membrane of enterocytes. Despite these interactions, segmented filamentous bacteria were not always adjacent to the areas with pathological changes, suggesting that if these organisms play a role in the pathogenesis of RTGE, extracellular products may be involved. Ultrastructural changes included loss of microvillar structure, membrane blebbing, hydropic mitochondrial damage, and basal hydropic degeneration of enterocytes, which frequently resulted in disruption of tight junctions and enterocyte detachment. The resulting exposure of large areas of lamina propria probably resulted in the compromise of the host osmotic balance and the facilitation of the entry of secondary pathogens.
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Affiliation(s)
- J Del-Pozo
- Institute of Aquaculture, University of Stirling, Stirling, UK.
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28
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Fuentes S, Egert M, Jimenez-Valera M, Monteoliva-Sanchez M, Ruiz-Bravo A, Smidt H. A strain of Lactobacillus plantarum affects segmented filamentous bacteria in the intestine of immunosuppressed mice. FEMS Microbiol Ecol 2008; 63:65-72. [PMID: 18081591 DOI: 10.1111/j.1574-6941.2007.00411.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Segmented filamentous bacteria (SFB) are present in the gastrointestinal tract of mice from weaning until the maturation of the immune system. Probiotic bacteria also have an effect on host immunity. To study the relationships established between these bacteria, samples from a mouse model fed with Lactobacillus plantarum under different immunological conditions were analysed. SFB populations were measured by a newly designed group-specific quantitative PCR assay. The results confirmed the presence of the probiotic in the intestine and an expansion of SFB in the ileum of immunocompromised mice, which was abolished upon administration of L. plantarum, an effect not described to date.
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Affiliation(s)
- Susana Fuentes
- Department of Microbiology, School of Pharmacy, University of Granada, Granada, Spain.
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29
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Child MW, Kennedy A, Walker AW, Bahrami B, Macfarlane S, Macfarlane GT. Studies on the effect of system retention time on bacterial populations colonizing a three-stage continuous culture model of the human large gut using FISH techniques. FEMS Microbiol Ecol 2006; 55:299-310. [PMID: 16420637 DOI: 10.1111/j.1574-6941.2005.00016.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Fluorescence in situ hybridization was used to quantitate bacteria growing in a three-stage continuous culture system inoculated with human faeces, operated at two system retention times (60 and 20 h). Twenty-three different 16S rRNA gene oligonucleotide probes of varying specificities were used to detect bacteria. Organisms belonging to genera Bacteroides and Bifidobacterium, together with the Eubacterium rectale/Clostridium coccoides group, the Atopobium, Faecalibacterium prausnitzii and Eubacterium cylindroides groups, as well as the segmented filamentous bacteria, the Roseburia intestinalis group and lactic acid bacteria, were all present in high numbers in the continuous culture system. Other groups and species such as Ruminococci and Enterobacteria also persisted in the model, though not always at levels that allowed reliable quantitation. Some organisms such as Streptococci and Corynebacteria, present in the faecal inoculum, did not colonize the system. Other probes specific for Eubacterium lentum and for members of the genus Desulfovibrio did not detect these organisms at any time. Short chain fatty acid production was always highest in vessel I of the continuous culture system, however, a marked increase in acetate formation and a reduction in butyrate production occurred when system retention time was reduced to 20 h, which correlated with reductions in the numbers of butyrate-producing Roseburia.
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Affiliation(s)
- Matthew W Child
- Microbiology and Gut Biology Group, University of Dundee, Ninewells Hospital Medical School, Dundee, UK
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Swidsinski A, Göktas O, Bessler C, Loening-Baucke V, Hale LP, Andree H, Weizenegger M, Hölzl M, Scherer H, Lochs H. Spatial organisation of microbiota in quiescent adenoiditis and tonsillitis. J Clin Pathol 2006; 60:253-60. [PMID: 16698947 PMCID: PMC1860565 DOI: 10.1136/jcp.2006.037309] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND The reasons for recurrent adenotonsillitis are poorly understood. METHODS The in situ composition of microbiota of nasal (5 children, 25 adults) and of hypertrophied adenoid and tonsillar tissue (50 children, 20 adults) was investigated using a broad range of fluorescent oligonucleotide probes targeted to bacterial rRNA. None of the patients had clinical signs of infection at the time of surgery. RESULTS Multiple foci of ongoing purulent infections were found within hypertrophied adenoid and tonsillar tissue in 83% of patients, including islands and lawns of bacteria adherent to the epithelium, with concomitant marked inflammatory response, fissures filled with bacteria and pus, and diffuse infiltration of the tonsils by bacteria, microabscesses, and macrophages containing phagocytosed microorganisms. Haemophilusinfluenzae mainly diffusely infiltrated the tissue, Streptococcus and Bacteroides were typically found in fissures, and Fusobacteria,Pseudomonas and Burkholderia were exclusively located within adherent bacterial layers and infiltrates. The microbiota were always polymicrobial. CONCLUSIONS Purulent processes persist during asymptomatic periods of adenotonsillitis. Most bacteria involved in this process are covered by a thick inflammatory infiltrate, are deeply invading, or are located within macrophages. The distribution of the bacteria within tonsils may be responsible for the failure of antibiotic treatment.
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Affiliation(s)
- A Swidsinski
- Medizinische Klinik, Charité Humboldt Universität, CCM, Molekular-genetisches Labor für polymikrobielle Infektionen und bakterielle Biofilme, Berlin, Germany.
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Swidsinski A, Mendling W, Loening-Baucke V, Ladhoff A, Swidsinski S, Hale LP, Lochs H. Adherent Biofilms in Bacterial Vaginosis. Obstet Gynecol 2005; 106:1013-23. [PMID: 16260520 DOI: 10.1097/01.aog.0000183594.45524.d2] [Citation(s) in RCA: 298] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Bacterial vaginosis is a common infectious disorder. Although known since ancient times, little progress has occurred in identifying causal factors. Our aims were to study the bacterial community structure and the spatial organization of microbiota on the epithelial surfaces of vaginal biopsy specimens. METHODS We investigated the composition and spatial organization of bacteria associated with the vaginal epithelium in biopsy specimens from 20 patients with bacterial vaginosis and 40 normal premenopausal and postmenopausal controls using a broad range of fluorescent bacterial group-specific rRNA-targeted oligonucleotide probes. RESULTS Bacterial vaginosis was associated with greater occurrence and higher concentrations of a variety of bacterial groups. However, only Gardnerella vaginalis developed a characteristic adherent biofilm that was specific for bacterial vaginosis. CONCLUSION A biofilm comprised of confluent G vaginalis with other bacterial groups incorporated in the adherent layer is a prominent feature of bacterial vaginosis. LEVEL OF EVIDENCE II-2.
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Swidsinski A, Weber J, Loening-Baucke V, Hale LP, Lochs H. Spatial organization and composition of the mucosal flora in patients with inflammatory bowel disease. J Clin Microbiol 2005; 43:3380-9. [PMID: 16000463 PMCID: PMC1169142 DOI: 10.1128/jcm.43.7.3380-3389.2005] [Citation(s) in RCA: 631] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The composition and spatial organization of the mucosal flora in biopsy specimens from patients with inflammatory bowel disease (IBD; either Crohn's disease or ulcerative colitis), self-limiting colitis, irritable-bowel syndrome (IBS), and healthy controls were investigated by using a broad range of fluorescent bacterial group-specific rRNA-targeted oligonucleotide probes. Each group included 20 subjects. Ten patients who had IBD and who were being treated with antibiotics were also studied. Use of nonaqueous Carnoy fixative to preserve the mucus layer was crucial for detection of bacteria adherent to the mucosal surface (mucosal bacteria). No biofilm was detectable in formalin-fixed biopsy specimens. Mucosal bacteria were found at concentrations greater than 10(9)/ml in 90 to 95% of IBD patients, 95% of patients with self-limiting colitis, 65% of IBS patients, and 35% of healthy controls. The mean density of the mucosal biofilm was 2 powers higher in IBD patients than in patients with IBS or controls, and bacteria were mostly adherent. Bacteroides fragilis was responsible for >60% of the biofilm mass in patients with IBD but for only 30% of the biofilm mass in patients with self-limiting colitis and <15% of the biofilm mass in patients with IBS. In contrast, bacteria which positively hybridized with the probe specific for Eubacterium rectale-Clostridium coccoides accounted for >40% of the biofilm in IBS patients but for <15% of the biofilm in IBD patients. In patients treated with (5-ASA) or antibiotics, the biofilm could be detected with 4,6-diamidino-2-phenylindole but did not hybridize with fluorescence in situ hybridization probes. A Bacteroides fragilis biofilm is the main feature of IBD. This was not previously recognized due to a lack of appropriate tissue fixation. Both 5-ASA and antibiotics suppress but do not eliminate the adherent biofilm.
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Affiliation(s)
- Alexander Swidsinski
- Innere Klinik, Gastroenterologie, Charité Humboldt Universität, 10098 Berlin, Germany.
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Swidsinski A, Loening-Baucke V, Lochs H, Hale LP. Spatial organization of bacterial flora in normal and inflamed intestine: A fluorescence in situ hybridization study in mice. World J Gastroenterol 2005; 11:1131-40. [PMID: 15754393 PMCID: PMC4250702 DOI: 10.3748/wjg.v11.i8.1131] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the role of intestinal flora in inflammatory bowel disease (IBD).
METHODS: The spatial organization of intestinal flora was investigated in normal mice and in two models of murine colitis using fluorescence in situ hybridization.
RESULTS: The murine small intestine was nearly bacteria-free. The normal colonic flora was organized in three distinct compartments (crypt, interlaced, and fecal), each with different bacterial compositions. Crypt bacteria were present in the cecum and proximal colon. The fecal compartment was composed of homogeneously mixed bacterial groups that directly contacted the colonic wall in the cecum but were separated from the proximal colonic wall by a dense interlaced layer. Beginning in the middle colon, a mucus gap of growing thickness physically separated all intestinal bacteria from contact with the epithelium. Colonic inflammation was accompanied with a depletion of bacteria within the fecal compartment, a reduced surface area in which feces had direct contact with the colonic wall, increased thickness and spread of the mucus gap, and massive increases of bacterial concentrations in the crypt and interlaced compartments. Adhesive and infiltrative bacteria were observed in inflamed colon only, with dominant Bacteroides species.
CONCLUSION: The proximal and distal colons are functionally different organs with respect to the intestinal flora, representing a bioreactor and a segregation device. The highly organized structure of the colonic flora, its specific arrangement in different colonic segments, and its specialized response to inflammatory stimuli indicate that the intestinal flora is an innate part of host immunity that is under complex control.
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Affiliation(s)
- Alexander Swidsinski
- Innere Klinik, Gastroenterologie, Charité Humboldt Universität, 10098 Berlin, Germany.
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Cebra JJ, Jiang HQ, Boiko N, Tlaskalova-Hogenova H. The Role of Mucosal Microbiota in the Development, Maintenance, and Pathologies of the Mucosal Immune System. Mucosal Immunol 2005. [PMCID: PMC7150267 DOI: 10.1016/b978-012491543-5/50022-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
Advances in molecular taxonomy of bacteria have generated many tools allowing identification of any bacteria, whether culturable or not. In addition to taxonomic identification, growing knowledge on pathogenicity mechanisms allows the detection of bacteria with given virulence genes. The problem is in asking the proper questions so that the most appropriate tools can be chosen. Some rapid identification tools (gene amplification, in situ hybridisation) require a starting hypothesis. Other tools (rrs gene amplification and sequencing) can be used without prior hypothesis, but take longer. To face the bioterrorist threat, particular attention should be given to laboratory and strain dispatch (within- and between-laboratory) organisation.
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Affiliation(s)
- Patrick A D Grimont
- Centre d'identification moléculaire des bactéries, unité de biodiversité des bactéries pathogènes émergentes et unité Inserm 389, Institut Pasteur, 28, rue du Docteur-Roux, 75724 Paris, France.
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