1
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Emsley SA, Loughran RM, Shlafstein MD, Pfannmuller KM, De La Flor YT, Lein CG, Dove NC, Koyack MJ, Oline DK, Hanson TE, Videau P, Saw JH, Ushijima B. Fluctibacter corallii gen. nov., sp. nov., isolated from the coral Montipora capitata on a reef in Kāne'ohe Bay, O'ahu, Hawai'i, reclassification of Aestuariibacter halophilus as Fluctibacter halophilus comb. nov., and Paraglaciecola oceanifecundans as a later heterotypic synonym of Paraglaciecola agarilytica. Antonie Van Leeuwenhoek 2024; 117:45. [PMID: 38424217 DOI: 10.1007/s10482-024-01934-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 01/25/2024] [Indexed: 03/02/2024]
Abstract
Strain AA17T was isolated from an apparently healthy fragment of Montipora capitata coral from the reef surrounding Moku o Lo'e in Kāne'ohe Bay, O'ahu, Hawai'i, USA, and was taxonomically evaluated using a polyphasic approach. Comparison of a partial 16S rRNA gene sequence found that strain AA17T shared the greatest similarity with Aestuariibacter halophilus JC2043T (96.6%), and phylogenies based on 16S rRNA gene sequences grouped strain AA17T with members of the Aliiglaciecola, Aestuariibacter, Lacimicrobium, Marisediminitalea, Planctobacterium, and Saliniradius genera. To more precisely infer the taxonomy of strain AA17T, a phylogenomic analysis was conducted and indicated that strain AA17T formed a monophyletic clade with A. halophilus JC2043T, divergent from Aestuariibacter salexigens JC2042T and other related genera. As a result of monophyly and multiple genomic metrics of genus demarcation, strain AA17T and A. halophilus JC2043T comprise a distinct genus for which the name Fluctibacter gen. nov. is proposed. Based on a polyphasic characterisation and identifying differences in genomic and taxonomic data, strain AA17T represents a novel species, for which the name Fluctibacter corallii sp. nov. is proposed. The type strain is AA17T (= LMG 32603 T = NCTC 14664T). This work also supports the reclassification of A. halophilus as Fluctibacter halophilus comb. nov., which is the type species of the Fluctibacter genus. Genomic analyses also support the reclassification of Paraglaciecola oceanifecundans as a later heterotypic synonym of Paraglaciecola agarilytica.
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Affiliation(s)
- Sarah A Emsley
- Department of Biology, Southern Oregon University, Ashland, OR, USA
| | - Rachel M Loughran
- Microbiology Graduate Program, University of Delaware, Newark, DE, USA
| | | | | | - Yesmarie T De La Flor
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC, USA
| | | | | | - Marc J Koyack
- School of Arts and Sciences, Gwynedd Mercy University, Gwynedd Valley, PA, USA
| | - David K Oline
- Department of Biology, Southern Oregon University, Ashland, OR, USA
| | - Thomas E Hanson
- Microbiology Graduate Program, University of Delaware, Newark, DE, USA
- School of Marine Science and Policy and Delaware Biotechnology Institute, University of Delaware, Delaware, USA
| | - Patrick Videau
- Department of Biology, Southern Oregon University, Ashland, OR, USA
- AgBiome, Research Triangle Park, NC, USA
| | - Jimmy H Saw
- Department of Biological Sciences, The George Washington University, Washington, DC, USA.
| | - Blake Ushijima
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC, USA.
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2
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Huang H, Zhong W, Wang X, Yang Y, Wu T, Chen R, Liu Y, He F, Li J. The role of gastric microecological dysbiosis in gastric carcinogenesis. Front Microbiol 2023; 14:1218395. [PMID: 37583514 PMCID: PMC10423824 DOI: 10.3389/fmicb.2023.1218395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 07/10/2023] [Indexed: 08/17/2023] Open
Abstract
Gastric cancer (GC) is the leading cause of cancer-related death worldwide, and reducing its mortality has become an urgent public health issue. Gastric microecological dysbiosis (including bacteria, fungi, viruses, acid suppressants, antibiotics, and surgery) can lead to gastric immune dysfunction or result in a decrease in dominant bacteria and an increase in the number and virulence of pathogenic microorganisms, which in turn promotes development of GC. This review analyzes the relationship between gastric microecological dysbiosis and GC, elucidates dynamic alterations of the microbiota in Correa's cascade, and identifies certain specific microorganisms as potential biomarkers of GC to aid in early screening and diagnosis. In addition, this paper presents the potential of gastric microbiota transplantation as a therapeutic target for gastric cancer, providing a new direction for future research in this field.
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Affiliation(s)
- Hui Huang
- Chengdu Medical College, Chengdu, Sichuan, China
| | - Wei Zhong
- Chengdu Medical College, Chengdu, Sichuan, China
| | | | - Ying Yang
- Chengdu Medical College, Chengdu, Sichuan, China
| | - Tianmu Wu
- Chengdu Medical College, Chengdu, Sichuan, China
| | - Runyang Chen
- Chengdu Medical College, Chengdu, Sichuan, China
| | - Yanling Liu
- Chengdu Medical College, Chengdu, Sichuan, China
| | - Feng He
- Chengdu Medical College, Chengdu, Sichuan, China
- Department of Gastroenterology, The First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Jun Li
- Chengdu Medical College, Chengdu, Sichuan, China
- Department of Gastroenterology, The First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
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3
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Wang Z, Shao SL, Xu XH, Zhao X, Wang MY, Chen A, Cong HY. Helicobacter pylori and gastric microbiota homeostasis: progress and prospects. Future Microbiol 2023; 18:137-157. [PMID: 36688318 DOI: 10.2217/fmb-2022-0102] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Helicobacter pylori, a Gram-negative microaerobic bacteria belonging to the phylum Proteobacteria, can colonize in the stomach and duodenum, and cause a series of gastrointestinal diseases such as gastritis, gastric ulcer and even gastric cancer. At present, the high diversity of the microorganisms in the stomach has been confirmed with culture-independent methods; some researchers have also studied the stomach microbiota composition at different stages of H. pylori carcinogenesis. Here, we mainly review the possible role of H. pylori-mediated microbiota changes in the occurrence and development of gastric cancer to provide new ideas for preventing H. pylori infection and regulating microecological imbalance.
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Affiliation(s)
- Zan Wang
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, 261053, People's Republic of China
| | - Shu-Li Shao
- Department of Central Lab, Weihai Municipal Hospital. Weihai, Shandong, 264200, People's Republic of China
| | - Xiao-Han Xu
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, 261053, People's Republic of China
| | - Xue Zhao
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, 261053, People's Republic of China
| | - Ming-Yi Wang
- Department of Central Lab, Weihai Municipal Hospital. Weihai, Shandong, 264200, People's Republic of China
| | - Ai Chen
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, 261053, People's Republic of China.,Department of Central Lab, Weihai Municipal Hospital. Weihai, Shandong, 264200, People's Republic of China
| | - Hai-Yan Cong
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, 261053, People's Republic of China.,Department of Central Lab, Weihai Municipal Hospital. Weihai, Shandong, 264200, People's Republic of China
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4
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Streptomyces spiramenti sp. nov., isolated from a deep-sea microbial mat. Arch Microbiol 2022; 204:717. [DOI: 10.1007/s00203-022-03326-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/25/2022] [Accepted: 11/07/2022] [Indexed: 11/21/2022]
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5
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Loughran RM, Emsley SA, Jefferson T, Wasson BJ, Deadmond MC, Knauss TL, Pfannmuller KM, Lippert KJ, Miller G, Cline LC, Oline DK, Koyack MJ, Grant-Beurmann S, Gaylor MO, Saw JH, Ushijima B, Videau P. Vibrio tetraodonis subsp. pristinus subsp. nov., isolated from the coral Acropora cytherea at Palmyra Atoll, and creation and emended description of Vibrio tetraodonis subsp. tetraodonis subsp. nov. Antonie Van Leeuwenhoek 2022; 115:1215-1228. [PMID: 35920985 DOI: 10.1007/s10482-022-01766-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 07/10/2022] [Indexed: 11/30/2022]
Abstract
Strain OCN044T was isolated from the homogenised tissue and mucus of an apparently healthy Acropora cytherea coral fragment collected from the western reef terrace of Palmyra Atoll in the Northern Line Islands and was taxonomically evaluated with a polyphasic approach. The morphological and chemotaxonomic properties are consistent with characteristics of the genus Vibrio: Gram-stain-negative rods, oxidase- and catalase-positive, and motile by means of a polar flagellum. Strain OCN044T can be differentiated as a novel subspecies based on 21 differences among chemotaxonomic features (e.g., fatty acids percentages for C12:0 and C18:1 ω7c), enzymatic activities (e.g., DNase and cystine arylamidase), and carbon sources utilized (e.g., L-xylose and D-melezitose) from its nearest genetic relative. Phylogenetic analysis and genomic comparisons show close evolutionary relatedness to Vibrio tetraodonis A511T but the overall genomic relatedness indices identify strain OCN044T as a distinct subspecies. Based on a polyphasic characterisation, differences in genomic and taxonomic data, strain OCN044T represents a novel subspecies of V. tetraodonis A511T, for which the name Vibrio tetraodonis subsp. pristinus subsp. nov. is proposed. The type strain is OCN044T (= LMG 31895T = DSM 111778T).
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Affiliation(s)
- Rachel M Loughran
- Department of Biology, Southern Oregon University, Ashland, OR, USA.,Microbiology Graduate Program, University of Delaware, Newark, DE, USA
| | - Sarah A Emsley
- Department of Biology, Southern Oregon University, Ashland, OR, USA
| | - Tori Jefferson
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC, USA
| | | | | | - Taylor L Knauss
- Department of Biology, Southern Oregon University, Ashland, OR, USA
| | | | - Katherine J Lippert
- Department of Biology, Southern Oregon University, Ashland, OR, USA.,Triplebar, Emeryville, CA, USA
| | - Gregory Miller
- Natural Sciences Department, Flagler College, St. Augustine, FL, USA
| | | | - David K Oline
- Department of Biology, Southern Oregon University, Ashland, OR, USA
| | - Marc J Koyack
- Department of Chemistry, Southern Oregon University, Ashland, OR, USA
| | - Silvia Grant-Beurmann
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Michael O Gaylor
- Department of Chemistry, Dakota State University, Madison, SD, USA
| | - Jimmy H Saw
- Department of Biological Sciences, The George Washington University, Washington, D.C, USA
| | - Blake Ushijima
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC, USA.
| | - Patrick Videau
- Department of Biology, Southern Oregon University, Ashland, OR, USA. .,Bayer Crop Science, Chesterfield, MO, USA.
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6
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Isaeva G, Isaeva R. Probiotics in the treatment of Helicobacter pylori infection: reality and perspective. Minerva Gastroenterol (Torino) 2022; 68:277-288. [PMID: 35001603 DOI: 10.23736/s2724-5985.21.02926-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Helicobacter pylori (H. pylori) infection is one of the most common in the world today, associated with the development of acute or chronic inflammatory diseases of the gastroduodenal tract. In order to eradicate the pathogen, various antibacterial therapy regimens have been proposed, based on the use of several chemotherapeutic drugs and a proton pump inhibitor (PPI). However, recent studies indicate a decrease in antibiotic effectiveness due to both the growth rate of H. pylori resistance and side effects, often due to the development of dysbiosis. One of the promising areas of investigation is the treatment with probiotic therapy of helicobacteriosis. The use of probiotics, in the context of H. pylori infection, has two main reasons. The first is related to the use of certain probiotics to reduce the frequency of undesirable gastrointestinal consequences during H. pylori eradication therapy. The second is associated with the antagonistic effect of individual probiotics on H. pylori and the potentiation of the eradication effect. The purpose of this review was to summarize the latest data on the use of probiotics to enhance H. pylori eradication and to restore the gastrointestinal microbiota. Many unresolved questions, about the choice of the specific composition of the probiotic cocktail, dosage, duration of therapy, mechanisms of the antimicrobial action of probiotics, as well as possible negative consequences of such therapy, remain.
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Affiliation(s)
- Guzel Isaeva
- Kazan Research Institute of Epidemiology and Microbiology, Kazan, Russian Federation - .,Microbiology Department, Kazan State Medical University, Kazan, Russian Federation -
| | - Regina Isaeva
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
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7
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Palrasu M, Zaika E, El-Rifai W, Que J, Zaika AI. Role of Bacterial and Viral Pathogens in Gastric Carcinogenesis. Cancers (Basel) 2021; 13:cancers13081878. [PMID: 33919876 PMCID: PMC8070847 DOI: 10.3390/cancers13081878] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/02/2021] [Accepted: 04/11/2021] [Indexed: 01/10/2023] Open
Abstract
Simple Summary Stomach cancer is one of the most common cancers in the world, with over one million new cases diagnosed in 2020. Despite recent advances in cancer treatments, gastric cancer remains a serious clinical problem. This disease is tightly linked to gastric infections with Helicobacter pylori bacterium, Epstein–Barr virus, and some other less known pathogens. Here, we discuss how gastric pathogens induce tumorigenic changes in the stomach. Abstract Gastric cancer (GC) is one of the deadliest malignancies worldwide. In contrast to many other tumor types, gastric carcinogenesis is tightly linked to infectious events. Infections with Helicobacter pylori (H. pylori) bacterium and Epstein–Barr virus (EBV) are the two most investigated risk factors for GC. These pathogens infect more than half of the world’s population. Fortunately, only a small fraction of infected individuals develops GC, suggesting high complexity of tumorigenic processes in the human stomach. Recent studies suggest that the multifaceted interplay between microbial, environmental, and host genetic factors underlies gastric tumorigenesis. Many aspects of these interactions still remain unclear. In this review, we update on recent discoveries, focusing on the roles of various gastric pathogens and gastric microbiome in tumorigenesis.
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Affiliation(s)
- Manikandan Palrasu
- Department of Surgery, University of Miami, Miami, FL 33136, USA; (M.P.); (E.Z.); (W.E.-R.)
| | - Elena Zaika
- Department of Surgery, University of Miami, Miami, FL 33136, USA; (M.P.); (E.Z.); (W.E.-R.)
| | - Wael El-Rifai
- Department of Surgery, University of Miami, Miami, FL 33136, USA; (M.P.); (E.Z.); (W.E.-R.)
- Department of Veterans Affairs, Miami VA Healthcare System, Miami, FL 33136, USA
| | - Jianwen Que
- Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA;
| | - Alexander I. Zaika
- Department of Surgery, University of Miami, Miami, FL 33136, USA; (M.P.); (E.Z.); (W.E.-R.)
- Department of Veterans Affairs, Miami VA Healthcare System, Miami, FL 33136, USA
- Correspondence:
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8
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Yang YJ, Chen PC, Lai FP, Tsai PJ, Sheu BS. Probiotics-Containing Yogurt Ingestion and H. pylori Eradication Can Restore Fecal Faecalibacterium prausnitzii Dysbiosis in H. pylori-Infected Children. Biomedicines 2020; 8:biomedicines8060146. [PMID: 32492860 PMCID: PMC7344718 DOI: 10.3390/biomedicines8060146] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 05/26/2020] [Accepted: 05/29/2020] [Indexed: 12/19/2022] Open
Abstract
This study investigated the compositional differences in fecal microbiota between children with and without H. pylori infection and tested whether probiotics-containing yogurt and bacterial eradication improve H. pylori-related dysbiosis. Ten H. pylori-infected children and 10 controls ingested probiotics-containing yogurt for 4 weeks. Ten-day triple therapy plus yogurt was given to the infected children on the 4th week. Fecal samples were collected at enrollment, after yogurt ingestion, and 4 weeks after successful H. pylori eradication for cytokines and microbiota analysis using ELISA and metagenomic sequencing of the V4 region of the 16S rRNA gene, respectively. The results showed H. pylori-infected children had significantly higher levels of fecal TGF-β1 than those who were not infected. Eight of 295 significantly altered OTUs in the H. pylori-infected children were identified. Among them, the abundance of F. prausnitzii was significantly lower in the H. pylori-infected children, and then increased after yogurt ingestion and successful bacterial eradication. We further confirmed probiotics promoted F. prausnitzii growth in vitro and in ex vivo using real-time PCR. Moreover, F. prausnitzii supernatant significantly ameliorated lipopolysaccharide-induced IL-8 in HT-29 cells. In conclusions, Probiotics-containing yogurt ingestion and H. pylori eradication can restore the decrease of fecal F. prausnitzii in H. pylori-infected children.
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Affiliation(s)
- Yao-Jong Yang
- Departments of Pediatrics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan; (Y.-J.Y.); (F.-P.L.)
- Institute of Clinical Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan;
| | - Peng-Chieh Chen
- Institute of Clinical Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan;
| | - Fu-Ping Lai
- Departments of Pediatrics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan; (Y.-J.Y.); (F.-P.L.)
| | - Pei-Jane Tsai
- Departments of Pathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan;
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan
| | - Bor-Shyang Sheu
- Departments of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan
- Internal Medicine & Institute of Clinical Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: ; Tel.: +886-6-235-3535 (ext. 5368); Fax: +886-6-237-0941
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9
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Stillhart C, Vučićević K, Augustijns P, Basit AW, Batchelor H, Flanagan TR, Gesquiere I, Greupink R, Keszthelyi D, Koskinen M, Madla CM, Matthys C, Miljuš G, Mooij MG, Parrott N, Ungell AL, de Wildt SN, Orlu M, Klein S, Müllertz A. Impact of gastrointestinal physiology on drug absorption in special populations––An UNGAP review. Eur J Pharm Sci 2020; 147:105280. [DOI: 10.1016/j.ejps.2020.105280] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 02/10/2020] [Accepted: 02/24/2020] [Indexed: 02/07/2023]
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10
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Pichon M, Burucoa C. Impact of the Gastro-Intestinal Bacterial Microbiome on Helicobacter-Associated Diseases. Healthcare (Basel) 2019; 7:E34. [PMID: 30813360 PMCID: PMC6473412 DOI: 10.3390/healthcare7010034] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 02/18/2019] [Accepted: 02/20/2019] [Indexed: 12/15/2022] Open
Abstract
Helicobacter pylori is a bacterium that selectively infects the gastric epithelium of half of the world population. The microbiome, community of microorganisms gained major interest over the last years, due to its modification associated to health and disease states. Even if most of these descriptions have focused on chronic disorders, this review describes the impact of the intestinal bacterial microbiome on host response to Helicobacter associated diseases. Microbiome has a direct impact on host cells, major barrier of the gastro-intestinal tract, but also an indirect impact on immune system stimulation, by enhancing or decreasing non-specific or adaptive response. In microbial infections, especially in precancerous lesions induced by Helicobacter pylori infection, these modifications could lead to different outcome. Associated to data focusing on the microbiome, transcriptomic analyses of the eukaryote response would lead to a complete understanding of these complex interactions and will allow to characterize innovative biomarkers and personalized therapies.
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Affiliation(s)
- Maxime Pichon
- Bacteriology and Infection Control Laboratory, Infectious Agents Department, University Hospital of Poitiers, 86021 Poitiers, France.
- Laboratoire Inflammation, Tissus Épithéliaux et Cytokines, EA 4331, Faculté de Médecine et de Pharmacie, University of Poitiers, 86022 Poitiers, France.
| | - Christophe Burucoa
- Bacteriology and Infection Control Laboratory, Infectious Agents Department, University Hospital of Poitiers, 86021 Poitiers, France.
- Laboratoire Inflammation, Tissus Épithéliaux et Cytokines, EA 4331, Faculté de Médecine et de Pharmacie, University of Poitiers, 86022 Poitiers, France.
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11
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Lopetuso LR, Napoli M, Rizzatti G, Scaldaferri F, Franceschi F, Gasbarrini A. Considering gut microbiota disturbance in the management of Helicobacter pylori infection. Expert Rev Gastroenterol Hepatol 2018; 12:899-906. [PMID: 30040500 DOI: 10.1080/17474124.2018.1503946] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Helicobacter pylori (Hp) infection produces drastic changes in the gastric microenvironment, which, in turn, influence the gastric microbiota composition and might be correlated with large intestinal microbiota changes. This excellent perturbing actor could trigger important modifications in the homeostatic functions exerted by gut commensals leading to a new gastrointestinal balance. At the same time, the therapeutic strategies used to eradicate Hp can modulate this physiological symbiosis, but can be also conversely affected by its properties. Area covered: The purpose of this review is to explore the reciprocal interplay between Hp infection and gut microbiota and analyze how microbial changes can influence the management of Hp eradication therapies. Expert commentary: While many studies have described Hp-dependent gut microbiota alterations, their clinical implications are only partially clear, as well as the mechanism of actions that sustain these processes. This represents a clear challenge for future research projects that will also need to understand which role is exerted by viruses, parasites, and yeasts.
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Affiliation(s)
- Loris R Lopetuso
- a Internal Medicine, Gastroenterology and Hepatology Department , Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore , Roma , Italy
| | - Marco Napoli
- a Internal Medicine, Gastroenterology and Hepatology Department , Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore , Roma , Italy
| | - Gianenrico Rizzatti
- a Internal Medicine, Gastroenterology and Hepatology Department , Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore , Roma , Italy
| | - Franco Scaldaferri
- a Internal Medicine, Gastroenterology and Hepatology Department , Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore , Roma , Italy
| | - Francesco Franceschi
- a Internal Medicine, Gastroenterology and Hepatology Department , Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore , Roma , Italy
| | - Antonio Gasbarrini
- a Internal Medicine, Gastroenterology and Hepatology Department , Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore , Roma , Italy
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12
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De Witte C, Taminiau B, Flahou B, Hautekiet V, Daube G, Ducatelle R, Haesebrouck F. In-feed bambermycin medication induces anti-inflammatory effects and prevents parietal cell loss without influencing Helicobacter suis colonization in the stomach of mice. Vet Res 2018; 49:35. [PMID: 29636083 PMCID: PMC5894178 DOI: 10.1186/s13567-018-0530-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/21/2018] [Indexed: 12/18/2022] Open
Abstract
The minimum inhibitory concentration of bambermycin on three porcine Helicobacter suis strains was shown to be 8 μg/mL. The effect of in-feed medication with this antibiotic on the course of a gastric infection with one of these strains, the host response and the gastric microbiota was determined in mice, as all of these parameters may be involved in gastric pathology. In H. suis infected mice which were not treated with bambermycin, an increased number of infiltrating B-cells, T-cells and macrophages in combination with a Th2 response was demonstrated, as well as a decreased parietal cell mass. Compared to this non-treated, infected group, in H. suis infected mice medicated with bambermycin, gastric H. suis colonization was not altered, but a decreased number of infiltrating T-cells, B-cells and macrophages as well as downregulated expressions of IL-1β, IL-8M, IL-10 and IFN-γ were demonstrated and the parietal cell mass was not affected. In bambermycin treated mice that were not infected with H. suis, the number of infiltrating T-cells and expression of IL-1β were lower than in non-infected mice that did not receive bambermycin. Gastric microbiota analysis indicated that the relative abundance of bacteria that might exert unfavorable effects on the host was decreased during bambermycin supplementation. In conclusion, bambermycin did not affect H. suis colonization, but decreased gastric inflammation and inhibited the effects of a H. suis infection on parietal cell loss. Not only direct interaction of H. suis with parietal cells, but also inflammation may play a role in death of these gastric acid producing cells.
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Affiliation(s)
- Chloë De Witte
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Bernard Taminiau
- Department of Food Sciences, FARAH, Université de Liège, Avenue de Cureghem 10, 4000, Liège, Belgium
| | - Bram Flahou
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | | | - Georges Daube
- Department of Food Sciences, FARAH, Université de Liège, Avenue de Cureghem 10, 4000, Liège, Belgium
| | - Richard Ducatelle
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Freddy Haesebrouck
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
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Dias-Jácome E, Libânio D, Borges-Canha M, Galaghar A, Pimentel-Nunes P. Gastric microbiota and carcinogenesis: the role of non-Helicobacter pylori bacteria - A systematic review. REVISTA ESPANOLA DE ENFERMEDADES DIGESTIVAS 2017; 108:530-40. [PMID: 27604361 DOI: 10.17235/reed.2016.4261/2016] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND AND AIM Helicobacter pylori is the strongest risk factor for gastric cancer. However, recent advances in DNA sequencing technology have revealed a complex microbial community in the stomach that could also contribute to the development of gastric cancer. The aim of this study was to present recent scientific evidence regarding the role of non-Helicobacter pylori bacteria in gastric carcinogenesis. METHODS A systematic review of original articles published in PubMed in the last ten years related to gastric microbiota and gastric cancer in humans was performed. RESULTS Thirteen original articles were included. The constitution of gastric microbiota appears to be significantly affected by gastric cancer and premalignant lesions. In fact, differences in gastric microbiota have been documented, depending on Helicobacter pylori status and gastric conditions, such as non-atrophic gastritis, intestinal metaplasia and cancer. Gastric carcinogenesis can be associated with an increase in many bacteria (such as Lactobacillus coleohominis, Klebsiella pneumoniae or Acinetobacter baumannii) as well as decrease in others (such as Porphyromonas spp, Neisseria spp, Prevotella pallens or Streptococcus sinensis). However, there is no conclusive data that confirms if these changes in microbiota are a cause or consequence of the process of carcinogenesis. CONCLUSIONS Even though there is limited evidence in humans, microbiota differences between normal individuals, pre-malignant lesions and gastric cancer could suggest a progressive shift in the constitution of gastric microbiota in carcinogenesis, possibly resulting from a complex cross-talk between gastric microbiota and Helicobacter pylori. However, further studies are needed to elucidate the specific role (if any) of different microorganisms.
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Affiliation(s)
| | - Diogo Libânio
- Gastroenterology Department, Oncology Portuguese Institute of Porto, Portugal
| | - Marta Borges-Canha
- Physiology and Cardiothoracic Surgery, Faculty of Medicine, University of Porto, Portugal
| | - Ana Galaghar
- Pathology Department, Oncology Portuguese Institute of Porto, Portugal
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Jones TA, Hernandez DZ, Wong ZC, Wandler AM, Guillemin K. The bacterial virulence factor CagA induces microbial dysbiosis that contributes to excessive epithelial cell proliferation in the Drosophila gut. PLoS Pathog 2017; 13:e1006631. [PMID: 29049360 PMCID: PMC5648253 DOI: 10.1371/journal.ppat.1006631] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/06/2017] [Indexed: 02/07/2023] Open
Abstract
Gut microbiota facilitate many aspects of human health and development, but dysbiotic microbiota can promote hyperplasia and inflammation and contribute to human diseases such as cancer. Human patients infected with the gastric cancer-causing bacterium Helicobacter pylori have altered microbiota; however, whether dysbiosis contributes to disease in this case is unknown. Many H. pylori human disease phenotypes are associated with a potent virulence protein, CagA, which is translocated into host epithelial cells where it alters cell polarity and manipulates host-signaling pathways to promote disease. We hypothesized that CagA alone could contribute to H. pylori pathogenesis by inducing microbial dysbiosis that promotes disease. Here we use a transgenic Drosophila model of CagA expression to genetically disentangle the effects of the virulence protein CagA from that of H. pylori infection. We found that expression of CagA within Drosophila intestinal stem cells promotes excess cell proliferation and is sufficient to alter host microbiota. Rearing CagA transgenic flies germ-free revealed that the dysbiotic microbiota contributes to cell proliferation phenotypes and also elicits expression of innate immune components, Diptericin and Duox. Further investigations revealed interspecies interactions are required for this dysbiotic CagA-dependent microbiota to promote proliferation in CagA transgenic and healthy control Drosophila. Our model establishes that CagA can alter gut microbiota and exacerbate cell proliferation and immune phenotypes previously attributed to H. pylori infection. This work provides valuable new insights into the mechanisms by which interactions between a specific virulence factor and the resident microbiota can contribute to the development and progression of disease. Microbial communities in the gut, termed microbiota are important for human health, and when altered can sometimes promote disease. Infections, such as with the cancer-causing bacterium Helicobacter pylori, can cause altered gut microbiota, but why these alterations occur and whether the altered communities contribute to disease remain unknown. Here, we use Drosophila expressing the H. pylori disease-causing protein CagA, to model this virulence factor’s effect on host pathology and microbiota. We found that expression of CagA in the Drosophila gut causes excessive cell proliferation and immune activation, hallmarks of H. pylori infection. Notably, these traits did not occur when flies were reared in the absence of microbes. Further examination reveals that CagA-expressing flies have an altered gut microbial community that is sufficient to promote cell proliferation even in normal flies. This proliferative activity required the presence of two interacting bacteria, illustrating a new model for disease-promoting microbiota. This work demonstrates how a bacterial protein can cause disease indirectly through altering the microbial ecology of the host, and it suggests future treatments for infections that rely on manipulating the microbiota to mitigate disease pathology.
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Affiliation(s)
- Tiffani Alvey Jones
- Institute of Molecular Biology, University of Oregon, Eugene, OR, United States of America
| | - Diane Z. Hernandez
- Institute of Molecular Biology, University of Oregon, Eugene, OR, United States of America
| | - Zoë C. Wong
- Institute of Molecular Biology, University of Oregon, Eugene, OR, United States of America
| | - Anica M. Wandler
- Institute of Molecular Biology, University of Oregon, Eugene, OR, United States of America
| | - Karen Guillemin
- Institute of Molecular Biology, University of Oregon, Eugene, OR, United States of America
- Humans and the Microbiome Program, Canadian Institute for Advanced Research, Toronto, Ontario, Canada
- * E-mail:
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15
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Beurmann S, Ushijima B, Svoboda CM, Videau P, Smith AM, Donachie SP, Aeby GS, Callahan SM. Pseudoalteromonas piratica sp. nov., a budding, prosthecate bacterium from diseased Montipora capitata, and emended description of the genus Pseudoalteromonas. Int J Syst Evol Microbiol 2017; 67:2683-2688. [PMID: 28792373 DOI: 10.1099/ijsem.0.001995] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A Gram-stain-negative, motile, rod-shaped bacterium designated OCN003T was cultivated from mucus taken from a diseased colony of the coral Montipora capitata in Kāne'ohe Bay, O'ahu, Hawai'i. Colonies of OCN003T were pale yellow, 1-3 mm in diameter, convex, smooth and entire. The strain was heterotrophic, strictly aerobic and strictly halophilic. Cells of OCN003T produced buds on peritrichous prosthecae. Growth occurred within the pH range of 5.5 to 10, and the temperature range of 14 to 39 °C. Major fatty acids were 16 : 1ω7c, 16 : 0, 18 : 1ω7c, 17 : 1ω8c, 12 : 0 3-OH and 17 : 0. Phylogenetic analysis of 1399 nucleotides of the 16S rRNA gene nucleotide sequence and a multi-locus sequence analysis of three genes placed OCN003T in the genus Pseudoalteromonas and indicated that the nearest relatives described are Pseudoalteromonas spongiae, P. luteoviolacea, P. ruthenica and P. phenolica(97-99 % sequence identity). The DNA G+C content of the strain's genome was 40.0 mol%. Based on in silico DNA-DNA hybridization and phenotypic differences from related type strains, we propose that OCN003T represents the type strain of a novel species in the genus Pseudoalteromonas, proposed as Pseudoalteromonas piratica sp. nov. OCN003T (=CCOS1042T=CIP 111189T). An emended description of the genus Pseudoalteromonas is presented.
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Affiliation(s)
- Silvia Beurmann
- Present address: Institute for GenomeSciences, School of Medicine, University of Maryland, Baltimore, MD 21201, USA.,Hawai'i Institute of Marine Biology, 46-007 Lilipuna Road, Kāne'ohe, HI 96744, USA.,Department of Microbiology, University of Hawai'i at Mānoa, 2538 McCarthy Mall, Snyder Hall, Honolulu, HI 96822, USA
| | - Blake Ushijima
- College of Veterinary Medicine, Oregon State University, 105 Magruder Hall, 700 SW 30th Street, Corvallis, OR 97331, USA
| | - Christina M Svoboda
- Hawai'i Institute of Marine Biology, 46-007 Lilipuna Road, Kāne'ohe, HI 96744, USA
| | - Patrick Videau
- Biology Department, Dakota State University, College of Arts and Sciences, Science Center, 820 N Washington Ave, Madison, SD 57042, USA
| | - Ashley M Smith
- Department of Microbiology, University of Hawai'i at Mānoa, 2538 McCarthy Mall, Snyder Hall, Honolulu, HI 96822, USA.,Hawai'i Institute of Marine Biology, 46-007 Lilipuna Road, Kāne'ohe, HI 96744, USA
| | - Stuart P Donachie
- Department of Microbiology, University of Hawai'i at Mānoa, 2538 McCarthy Mall, Snyder Hall, Honolulu, HI 96822, USA
| | - Greta S Aeby
- Hawai'i Institute of Marine Biology, 46-007 Lilipuna Road, Kāne'ohe, HI 96744, USA
| | - Sean M Callahan
- Department of Microbiology, University of Hawai'i at Mānoa, 2538 McCarthy Mall, Snyder Hall, Honolulu, HI 96822, USA.,Hawai'i Institute of Marine Biology, 46-007 Lilipuna Road, Kāne'ohe, HI 96744, USA
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16
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Lopez A, Hansmannel F, Kokten T, Bronowicki JP, Melhem H, Sokol H, Peyrin-Biroulet L. Microbiota in digestive cancers: our new partner? Carcinogenesis 2017; 38:1157-1166. [DOI: 10.1093/carcin/bgx087] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 08/09/2017] [Indexed: 01/01/2023] Open
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17
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Helicobacter pylori, Cancer, and the Gastric Microbiota. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 908:393-408. [PMID: 27573782 DOI: 10.1007/978-3-319-41388-4_19] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Gastric adenocarcinoma is one of the leading causes of cancer-related death worldwide and Helicobacter pylori infection is the strongest known risk factor for this disease. Although the stomach was once thought to be a sterile environment, it is now known to house many bacterial species leading to a complex interplay between H. pylori and other residents of the gastric microbiota. In addition to the role of H. pylori virulence factors, host genetic polymorphisms, and diet, it is now becoming clear that components of the gastrointestinal microbiota may also influence H. pylori-induced pathogenesis. In this chapter, we discuss emerging data regarding the gastric microbiota in humans and animal models and alterations that occur to the composition of the gastric microbiota in the presence of H. pylori infection that may augment the risk of developing gastric cancer.
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18
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He C, Yang Z, Lu N. Imbalance of Gastrointestinal Microbiota in the Pathogenesis of Helicobacter pylori-Associated Diseases. Helicobacter 2016; 21:337-48. [PMID: 26876927 DOI: 10.1111/hel.12297] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The development of new nucleotide sequencing techniques and advanced bioinformatics tools has opened the field for studying the diversity and complexity of the gastrointestinal microbiome independent of traditional cultural methods. Owing largely to the gastric acid barrier, the human stomach was long thought to be sterile. The discovery of Helicobacter pylori, the gram-negative bacterium that infects upwards of 50% of the global population, has started a major paradigm shift in our understanding of the stomach as an ecologic niche for bacteria. Recent sequencing analysis of gastric microbiota showed that H. pylori was not alone and the interaction of H. pylori with those microorganisms might play a part in H. pylori-associated diseases such as gastric cancer. In this review, we summarize the available literature about the changes of gastrointestinal microbiota after H. pylori infection in humans and animal models, and discuss the possible underlying mechanisms including the alterations of the gastric environment, the secretion of hormones and the degree of inflammatory response. In general, information regarding the composition and function of gastrointestinal microbiome is still in its infancy, future studies are needed to elucidate whether and to what extent H. pylori infection perturbs the established microbiota. It is assumed that clarifying the role of gastrointestinal communities in H. pylori-associated diseases will provide an opportunity for translational application as a biomarker for the risk of serious H. pylori diseases and perhaps identify specific organisms for therapeutic eradication.
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Affiliation(s)
- Cong He
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi Province, China
| | - Zhen Yang
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi Province, China
| | - Nonghua Lu
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi Province, China.
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19
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Wroblewski LE, Peek RM, Coburn LA. The Role of the Microbiome in Gastrointestinal Cancer. Gastroenterol Clin North Am 2016; 45:543-56. [PMID: 27546848 PMCID: PMC4994977 DOI: 10.1016/j.gtc.2016.04.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Humans are host to complex microbial communities previously termed normal flora and largely overlooked. However, resident microbes contribute to both health and disease. Investigators are beginning to define microbes that contribute to the development of gastrointestinal malignancies and the mechanisms by which this occurs. Resident microbes can induce inflammation, leading to cell proliferation and altered stem cell dynamics, which can lead to alterations in DNA integrity and immune regulation and promote carcinogenesis. Studies in human patients and rodent models of cancer have identified alterations in the microbiota of the stomach, esophagus, and colon that increase the risk for malignancy.
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Affiliation(s)
- Lydia E. Wroblewski
- Division of Gastroenterology, Department of Medicine; Vanderbilt University School of Medicine; Nashville, TN USA, T: 615-322-4215
| | - Richard M. Peek
- Division of Gastroenterology, Department of Medicine; Vanderbilt University School of Medicine; Nashville, TN USA, T: 615-343-1596
| | - Lori A. Coburn
- Veterans Affairs Tennessee Valley Healthcare System; Division of Gastroenterology, Department of Medicine; Vanderbilt University School of Medicine; Nashville, TN USA, T: 615-875-4222, F: 615-343-4229
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20
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Haley BJ, Pettengill J, Gorham S, Ottesen A, Karns JS, Van Kessel JAS. Comparison of Microbial Communities Isolated from Feces of Asymptomatic Salmonella-Shedding and Non-Salmonella Shedding Dairy Cows. Front Microbiol 2016; 7:691. [PMID: 27313565 PMCID: PMC4887466 DOI: 10.3389/fmicb.2016.00691] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 04/26/2016] [Indexed: 01/06/2023] Open
Abstract
In the United States Salmonella enterica subsp. enterica serotypes Kentucky and Cerro are frequently isolated from asymptomatic dairy cows. However, factors that contribute to colonization of the bovine gut by these two serotypes have not been identified. To investigate associations between Salmonella status and bacterial diversity, as well as the diversity of the microbial community in the dairy cow hindgut, the bacterial and archaeal communities of fecal samples from cows on a single dairy farm were determined by high-throughput sequencing of 16S rRNA gene amplicons. Fecal grab samples were collected from two Salmonella-positive cows and two Salmonella-negative cows on five sampling dates (n = 20 cows), and 16S rRNA gene amplicons from these samples were sequenced on the Illumina MiSeq platform. A high level of alpha (within) and beta diversity (between) samples demonstrated that microbial profiles of dairy cow hindguts are quite diverse. To determine whether Salmonella presence, sampling year, or sampling date explained a significant amount of the variation in microbial diversity, we performed constrained ordination analyses (distance based RDA) on the unifrac distance matrix produced with QIIME. Results indicated that there was not a significant difference in the microbial diversity associated with Salmonella presence (P > 0.05), but there were significant differences between sampling dates and years (Pseudo-F = 2.157 to 4.385, P < 0.05). Based on these data, it appears that commensal Salmonella infections with serotypes Cerro and Kentucky in dairy cows have little or no association with changes in the abundance of major bacterial groups in the hindgut. Rather, our results indicated that temporal dynamics and other undescribed parameters associated with them were the most influential drivers of the differences in microbial diversity and community structure in the dairy cow hindgut.
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Affiliation(s)
- Bradd J Haley
- Environmental Microbial and Food Safety Laboratory, Beltsville Agricultural Research Center, U.S. Department of Agriculture, Agricultural Research Service Beltsville, MD, USA
| | - James Pettengill
- Division of Public Health Informatics and Analytics, Center for Food Safety and Nutrition, Office of Analytics and Outreach, U.S. Food and Drug Administration College Park, MD, USA
| | - Sasha Gorham
- Division of Microbiology, Center for Food Safety and Nutrition, Office of Regulatory Science, U.S. Food and Drug Administration College Park, MD, USA
| | - Andrea Ottesen
- Division of Microbiology, Center for Food Safety and Nutrition, Office of Regulatory Science, U.S. Food and Drug Administration College Park, MD, USA
| | - Jeffrey S Karns
- Environmental Microbial and Food Safety Laboratory, Beltsville Agricultural Research Center, U.S. Department of Agriculture, Agricultural Research Service Beltsville, MD, USA
| | - Jo Ann S Van Kessel
- Environmental Microbial and Food Safety Laboratory, Beltsville Agricultural Research Center, U.S. Department of Agriculture, Agricultural Research Service Beltsville, MD, USA
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21
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Differences in Bacterial Community Structure in Two Color Morphs of the Hawaiian Reef Coral Montipora capitata. Appl Environ Microbiol 2015; 81:7312-8. [PMID: 26253663 DOI: 10.1128/aem.01935-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/04/2015] [Indexed: 12/20/2022] Open
Abstract
Corals harbor diverse bacterial associations that contribute to the health of the host. Using 16S rRNA pyrosequencing, we compared the bacterial communities of red and orange morphs of the Hawaiian coral Montipora capitata. Although both color morphs shared dominant bacterial genera, weighted and unweighted UniFrac analyses showed distinct bacterial communities. A single operational taxonomic unit (OTU), classified as Vibrio, represented the largest driver of differences between the color morphs. This OTU comprised 35.4% (±5.5%) of the orange morph bacterial community yet comprised 1.1% (±0.6%) of the red morph bacterial community. Cultivable bacteria from the two color morphs were also compared and tested for antibacterial activity. Cultured isolates represented 14 genera (7% of the total genera identified from sequencing data), and all but two cultured isolates had a matching OTU from the sequencing data. Half of the isolates tested (8 out of 16) displayed antibacterial activity against other cultured isolates but not against two known bacterial pathogens of M. capitata. The results from this study demonstrate that the specificity of coral-bacterial associations extends beyond the level of coral species. In addition, culture-dependent methods captured bacterial diversity that was representative of both rare and abundant members of the associated bacterial community, as characterized by culture-independent methods.
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22
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Aeby GS, Work TM, Runyon CM, Shore-Maggio A, Ushijima B, Videau P, Beurmann S, Callahan SM. First record of black band disease in the Hawaiian archipelago: response, outbreak status, virulence, and a method of treatment. PLoS One 2015; 10:e0120853. [PMID: 25774800 PMCID: PMC4361573 DOI: 10.1371/journal.pone.0120853] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 01/27/2015] [Indexed: 11/19/2022] Open
Abstract
A high number of coral colonies, Montipora spp., with progressive tissue loss were reported from the north shore of Kaua'i by a member of the Eyes of the Reef volunteer reporting network. The disease has a distinct lesion (semi-circular pattern of tissue loss with an adjacent dark band) that was first observed in Hanalei Bay, Kaua'i in 2004. The disease, initially termed Montipora banded tissue loss, appeared grossly similar to black band disease (BBD), which affects corals worldwide. Following the initial report, a rapid response was initiated as outlined in Hawai'i's rapid response contingency plan to determine outbreak status and investigate the disease. Our study identified the three dominant bacterial constituents indicative of BBD (filamentous cyanobacteria, sulfate-reducing bacteria, sulfide-oxidizing bacteria) in coral disease lesions from Kaua'i, which provided the first evidence of BBD in the Hawaiian archipelago. A rapid survey at the alleged outbreak site found disease to affect 6-7% of the montiporids, which is higher than a prior prevalence of less than 1% measured on Kaua'i in 2004, indicative of an epizootic. Tagged colonies with BBD had an average rate of tissue loss of 5.7 cm2/day over a two-month period. Treatment of diseased colonies with a double band of marine epoxy, mixed with chlorine powder, effectively reduced colony mortality. Within two months, treated colonies lost an average of 30% less tissue compared to untreated controls.
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Affiliation(s)
- Greta S. Aeby
- Hawai‘i Institute of Marine Biology, Kāne‘ohe, Hawaii, United States of America
- Marine Biology Graduate Program, University of Hawai‘i, Honolulu, Hawaii, United States of America
- * E-mail:
| | - Thierry M. Work
- U.S. Geological Survey, National Wildlife Health Center, Honolulu Field Station, Honolulu, Hawaii, United States of America
| | - Christina M. Runyon
- Hawai‘i Institute of Marine Biology, Kāne‘ohe, Hawaii, United States of America
- Marine Biology Graduate Program, University of Hawai‘i, Honolulu, Hawaii, United States of America
| | - Amanda Shore-Maggio
- Hawai‘i Institute of Marine Biology, Kāne‘ohe, Hawaii, United States of America
- Microbiology Department, University of Hawai‘i, Honolulu, Hawaii, United States of America
| | - Blake Ushijima
- Hawai‘i Institute of Marine Biology, Kāne‘ohe, Hawaii, United States of America
- Microbiology Department, University of Hawai‘i, Honolulu, Hawaii, United States of America
| | - Patrick Videau
- Microbiology Department, University of Hawai‘i, Honolulu, Hawaii, United States of America
| | - Silvia Beurmann
- Hawai‘i Institute of Marine Biology, Kāne‘ohe, Hawaii, United States of America
- Microbiology Department, University of Hawai‘i, Honolulu, Hawaii, United States of America
| | - Sean M. Callahan
- Hawai‘i Institute of Marine Biology, Kāne‘ohe, Hawaii, United States of America
- Marine Biology Graduate Program, University of Hawai‘i, Honolulu, Hawaii, United States of America
- Microbiology Department, University of Hawai‘i, Honolulu, Hawaii, United States of America
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23
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Lopetuso LR, Scaldaferri F, Franceschi F, Gasbarrini A. The gastrointestinal microbiome - functional interference between stomach and intestine. Best Pract Res Clin Gastroenterol 2014; 28:995-1002. [PMID: 25439066 DOI: 10.1016/j.bpg.2014.10.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Revised: 10/09/2014] [Accepted: 10/10/2014] [Indexed: 01/31/2023]
Abstract
The gastrointestinal (GI) tract is a complex and dynamic network with interplay between various gut mucosal cells and their defence molecules, the immune system, food particles, and the resident microbiota. This ecosystem acts as a functional unit organized as a semipermeable multi-layer system that allows the absorption of nutrients and macromolecules required for human metabolic processes and, on the other hand, protects the individual from potentially invasive microorganisms. Commensal microbiota and the host are a unique entity in a continuum along the GI tract, every change in one of these players is able to modify the whole homeostasis. In the stomach, Helicobacter pylori is a gram-negative pathogen that is widespread all over the world, infecting more than 50% of the world's population. In this scenario, H. pylori infection is associated with changes in the gastric microenvironment, which in turn affects the gastric microbiota composition, but also might trigger large intestinal microbiota changes. It is able to influence all the vital pathways of human system and also to influence microbiota composition along the GI tract. This can cause a change in the normal functions exerted by intestinal commensal microorganisms leading to a new gastrointestinal physiological balance. This review focuses and speculates on the possible interactions between gastric microorganisms and intestinal microbiota and on the consequences of this interplay in modulating gut health.
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Affiliation(s)
- Loris R Lopetuso
- Department of Internal Medicine, Gastroenterology Division, Catholic University of Rome, Policlinico "A. Gemelli" Hospital, Roma 00168, Italy.
| | - Franco Scaldaferri
- Department of Internal Medicine, Gastroenterology Division, Catholic University of Rome, Policlinico "A. Gemelli" Hospital, Roma 00168, Italy.
| | - Francesco Franceschi
- Department of Internal Medicine, Gastroenterology Division, Catholic University of Rome, Policlinico "A. Gemelli" Hospital, Roma 00168, Italy.
| | - Antonio Gasbarrini
- Department of Internal Medicine, Gastroenterology Division, Catholic University of Rome, Policlinico "A. Gemelli" Hospital, Roma 00168, Italy.
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Khosravi Y, Dieye Y, Loke MF, Goh KL, Vadivelu J. Streptococcus mitis induces conversion of Helicobacter pylori to coccoid cells during co-culture in vitro. PLoS One 2014; 9:e112214. [PMID: 25386948 PMCID: PMC4227722 DOI: 10.1371/journal.pone.0112214] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 10/10/2014] [Indexed: 12/18/2022] Open
Abstract
Helicobacter pylori (H. pylori) is a major gastric pathogen that has been associated with humans for more than 60,000 years. H. pylori causes different gastric diseases including dyspepsia, ulcers and gastric cancers. Disease development depends on several factors including the infecting H. pylori strain, environmental and host factors. Another factor that might influence H. pylori colonization and diseases is the gastric microbiota that was overlooked for long because of the belief that human stomach was a hostile environment that cannot support microbial life. Once established, H. pylori mainly resides in the gastric mucosa and interacts with the resident bacteria. How these interactions impact on H. pylori-caused diseases has been poorly studied in human. In this study, we analyzed the interactions between H. pylori and two bacteria, Streptococcus mitis and Lactobacillus fermentum that are present in the stomach of both healthy and gastric disease human patients. We have found that S. mitis produced and released one or more diffusible factors that induce growth inhibition and coccoid conversion of H. pylori cells. In contrast, both H. pylori and L. fermentum secreted factors that promote survival of S. mitis during the stationary phase of growth. Using a metabolomics approach, we identified compounds that might be responsible for the conversion of H. pylori from spiral to coccoid cells. This study provide evidences that gastric bacteria influences H. pylori physiology and therefore possibly the diseases this bacterium causes.
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Affiliation(s)
- Yalda Khosravi
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yakhya Dieye
- Vice-chancellor's Office, University of Malaya, Kuala Lumpur, Malaysia
| | - Mun Fai Loke
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Khean Lee Goh
- Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Jamuna Vadivelu
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- * E-mail:
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25
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Heimesaat MM, Fischer A, Plickert R, Wiedemann T, Loddenkemper C, Göbel UB, Bereswill S, Rieder G. Helicobacter pylori induced gastric immunopathology is associated with distinct microbiota changes in the large intestines of long-term infected Mongolian gerbils. PLoS One 2014; 9:e100362. [PMID: 24941045 PMCID: PMC4062524 DOI: 10.1371/journal.pone.0100362] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 05/27/2014] [Indexed: 12/16/2022] Open
Abstract
Background Gastrointestinal (GI) inflammation in mice and men are frequently accompanied by distinct changes of the GI microbiota composition at sites of inflammation. Helicobacter (H.) pylori infection results in gastric immunopathology accompanied by colonization of stomachs with bacterial species, which are usually restricted to the lower intestine. Potential microbiota shifts distal to the inflammatory process following long-term H. pylori infection, however, have not been studied so far. Methodology/Principal Findings For the first time, we investigated microbiota changes along the entire GI tract of Mongolian gerbils after 14 months of infection with H. pylori B8 wildtype (WT) or its isogenic ΔcagY mutant (MUT) strain which is defective in the type IV secretion system and thus unable to modulate specific host pathways. Comprehensive cultural analyses revealed that severe gastric diseases such as atrophic pangastritis and precancerous transformations were accompanied by elevated luminal loads of E. coli and enterococci in the caecum and together with Bacteroides/Prevotella spp. in the colon of H. pylori WT, but not MUT infected gerbils as compared to naïve animals. Strikingly, molecular analyses revealed that Akkermansia, an uncultivable species involved in mucus degradation, was exclusively abundant in large intestines of H. pylori WT, but not MUT infected nor naïve gerbils. Conclusion/Significance Taken together, long-term infection of Mongolian gerbils with a H. pylori WT strain displaying an intact type IV secretion system leads to distinct shifts of the microbiota composition in the distal uninflamed, but not proximal inflamed GI tract. Hence, H. pylori induced immunopathogenesis of the stomach, including hypochlorhydria and hypergastrinemia, might trigger large intestinal microbiota changes whereas the exact underlying mechanisms need to be further unraveled.
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Affiliation(s)
- Markus M. Heimesaat
- Department of Microbiology and Hygiene, Charité - University Medicine Berlin, Berlin, Germany
- * E-mail:
| | - André Fischer
- Department of Microbiology and Hygiene, Charité - University Medicine Berlin, Berlin, Germany
| | - Rita Plickert
- Department of Microbiology and Hygiene, Charité - University Medicine Berlin, Berlin, Germany
| | - Tobias Wiedemann
- German Research Center for Environmental Health, Helmholtz Zentrum München, Munich, Germany
| | - Christoph Loddenkemper
- Department of Pathology/Research Center ImmunoSciences (RCIS), Charité - University Medicine Berlin, Berlin, Germany
| | - Ulf B. Göbel
- Department of Microbiology and Hygiene, Charité - University Medicine Berlin, Berlin, Germany
| | - Stefan Bereswill
- Department of Microbiology and Hygiene, Charité - University Medicine Berlin, Berlin, Germany
| | - Gabriele Rieder
- Division of Molecular Biology, Department of Microbiology, University of Salzburg, Salzburg, Austria
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Wang LL, Yu XJ, Zhan SH, Jia SJ, Tian ZB, Dong QJ. Participation of microbiota in the development of gastric cancer. World J Gastroenterol 2014; 20:4948-4952. [PMID: 24803806 PMCID: PMC4009526 DOI: 10.3748/wjg.v20.i17.4948] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 12/10/2013] [Accepted: 01/08/2014] [Indexed: 02/06/2023] Open
Abstract
There are a large number of bacteria inhabiting the human body, which provide benefits for the health. Alterations of microbiota participate in the pathogenesis of diseases. The gastric microbiota consists of bacteria from seven to eleven phyla, predominantly Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria and Fusobacteria. Intrusion by Helicobacter pylori (H. pylori) does not remarkably interrupt the composition and structure of the gastric microbiota. Absence of bacterial commensal from the stomach delays the onset of H. pylori-induced gastric cancer, while presence of artificial microbiota accelerates the carcinogenesis. Altered gastric microbiota may increase the production of N-nitroso compounds, promoting the development of gastric cancer. Further investigation of the carcinogenic mechanisms of microbiota would benefit for the prevention and management of gastric cancer.
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Abreu MT, Peek RM. Gastrointestinal malignancy and the microbiome. Gastroenterology 2014; 146:1534-1546.e3. [PMID: 24406471 PMCID: PMC3995897 DOI: 10.1053/j.gastro.2014.01.001] [Citation(s) in RCA: 203] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 12/18/2013] [Accepted: 01/03/2014] [Indexed: 12/13/2022]
Abstract
Microbial species participate in the genesis of a substantial number of malignancies-in conservative estimates, at least 15% of all cancer cases are attributable to infectious agents. Little is known about the contribution of the gastrointestinal microbiome to the development of malignancies. Resident microbes can promote carcinogenesis by inducing inflammation, increasing cell proliferation, altering stem cell dynamics, and producing metabolites such as butyrate, which affect DNA integrity and immune regulation. Studies in human beings and rodent models of cancer have identified effector species and relationships among members of the microbial community in the stomach and colon that increase the risk for malignancy. Strategies to manipulate the microbiome, or the immune response to such bacteria, could be developed to prevent or treat certain gastrointestinal cancers.
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Affiliation(s)
- Maria T. Abreu
- Division of Gastroenterology, Departments of Medicine and Microbiology and Immunology, University of Miami, Miami, FL, USA
| | - Richard M. Peek
- Division of Gastroenterology, Departments of Medicine and Cancer Biology, Vanderbilt University, Nashville, TN, USA 37232
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Abstract
Bacteria are sparsely distributed in the stomach due to the gastric microbicidal barrier. Several innate defenses (low pH, migrating motor complex and the entero-salivary circulation of nitrate) as well as external factors (diet, Helicobacter pylori infection, proton pump inhibitors, antibiotics and stomach diseases) have been shown to influence significantly the microbiota composition in the stomach. In recent years new culture-independent technologies have allowed the investigation of the cross talk that occurs between hosts and stomach-associated microflora, which helps us to understand the role of gastric bacterial flora in the gastrointestinal microbiological system, both in physiological and pathological conditions. Here, we reviewed the literatures related to this topic and set the stage for future developments of the field.
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Affiliation(s)
- Wen Ming Wu
- Department of Gastroenterology and Hepatology, Chinese PLA General Hospital, Beijing, China
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Vibrio coralliilyticus strain OCN008 is an etiological agent of acute Montipora white syndrome. Appl Environ Microbiol 2014; 80:2102-9. [PMID: 24463971 DOI: 10.1128/aem.03463-13] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Identification of a pathogen is a critical first step in the epidemiology and subsequent management of a disease. A limited number of pathogens have been identified for diseases contributing to the global decline of coral populations. Here we describe Vibrio coralliilyticus strain OCN008, which induces acute Montipora white syndrome (aMWS), a tissue loss disease responsible for substantial mortality of the coral Montipora capitata in Kāne'ohe Bay, Hawai'i. OCN008 was grown in pure culture, recreated signs of disease in experimentally infected corals, and could be recovered after infection. In addition, strains similar to OCN008 were isolated from diseased coral from the field but not from healthy M. capitata. OCN008 repeatedly induced the loss of healthy M. capitata tissue from fragments under laboratory conditions with a minimum infectious dose of between 10(7) and 10(8) CFU/ml of water. In contrast, Porites compressa was not infected by OCN008, indicating the host specificity of the pathogen. A decrease in water temperature from 27 to 23°C affected the time to disease onset, but the risk of infection was not significantly reduced. Temperature-dependent bleaching, which has been observed with the V. coralliilyticus type strain BAA-450, was not observed during infection with OCN008. A comparison of the OCN008 genome to the genomes of pathogenic V. coralliilyticus strains BAA-450 and P1 revealed similar virulence-associated genes and quorum-sensing systems. Despite this genetic similarity, infections of M. capitata by OCN008 do not follow the paradigm for V. coralliilyticus infections established by the type strain.
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Abstract
The discovery of Helicobacter pylori overturned the conventional dogma that the stomach was a sterile organ and that pH values<4 were capable of sterilizing the stomach. H. pylori are an etiological agent associated with gastritis, hypochlorhydria, duodenal ulcers, and gastric cancer. It is now appreciated that the human stomach supports a bacterial community with possibly 100s of bacterial species that influence stomach homeostasis. Other bacteria colonizing the stomach may also influence H. pylori-associated gastric pathogenesis by creating reactive oxygen and nitrogen species and modulating inflammatory responses. In this review, we summarize the available literature concerning the gastric microbiota in humans, mice, and Mongolian gerbils. We also discuss the gastric perturbations, many involving H. pylori, that facilitate the colonization by bacteria from other compartments of the gastrointestinal tract, and identify risk factors known to affect gastric homeostasis that contribute to changes in the microbiota.
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Role of energy sensor TlpD of Helicobacter pylori in gerbil colonization and genome analyses after adaptation in the gerbil. Infect Immun 2013; 81:3534-51. [PMID: 23836820 DOI: 10.1128/iai.00750-13] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Helicobacter pylori maintains colonization in its human host using a limited set of taxis sensors. TlpD is a proposed energy taxis sensor of H. pylori and dominant under environmental conditions of low bacterial energy yield. We studied the impact of H. pylori TlpD on colonization in vivo using a gerbil infection model which closely mimics the gastric physiology of humans. A gerbil-adapted H. pylori strain, HP87 P7, showed energy-dependent behavior, while its isogenic tlpD mutant lost it. A TlpD-complemented strain regained the wild-type phenotype. Infection of gerbils with the complemented strain demonstrated that TlpD is important for persistent infection in the antrum and corpus and suggested a role of TlpD in horizontal navigation and persistent corpus colonization. As a part of the full characterization of the model and to gain insight into the genetic basis of H. pylori adaptation to the gerbil, we determined the complete genome sequences of the gerbil-adapted strain HP87 P7, two HP87 P7 tlpD mutants before and after gerbil passage, and the original human isolate, HP87. The integrity of the genome, including that of a functional cag pathogenicity island, was maintained after gerbil adaptation. Genetic and phenotypic differences between the strains were observed. Major differences between the gerbil-adapted strain and the human isolate emerged, including evidence of recent recombination. Passage of the tlpD mutant through the gerbil selected for gain-of-function variation in a fucosyltransferase gene, futC (HP0093). In conclusion, a gerbil-adapted H. pylori strain with a stable genome has helped to establish that TlpD has important functions for persistent colonization in the stomach.
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Bauer B, Pang E, Holland C, Kessler M, Bartfeld S, Meyer TF. The Helicobacter pylori virulence effector CagA abrogates human β-defensin 3 expression via inactivation of EGFR signaling. Cell Host Microbe 2012; 11:576-86. [PMID: 22704618 DOI: 10.1016/j.chom.2012.04.013] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 12/14/2011] [Accepted: 04/22/2012] [Indexed: 02/06/2023]
Abstract
Antimicrobial peptides are constituents of the first-line innate mucosal defense system that acts as a barrier to establishment of infection. The highly successful human gastric pathogen, Helicobacter pylori, is able to persistently colonize its host despite inducing expression of several antimicrobial peptides, including human β-defensin 3 (hBD3). We find that hBD3 is highly active against H. pylori in vitro and is rapidly induced during early infection via EGFR-dependent activation of MAP kinase and JAK/STAT signaling. However, during prolonged infection, hBD3 was subsequently downregulated by the H. pylori virulence determinant CagA. Upon translocation into host cells, CagA activated the cellular tyrosine phosphatase, SHP-2, terminating EGFR activation and downstream signaling and increasing bacterial viability. Chemical inhibition and knockdown of SHP-2 expression rescued hBD3 synthesis and bactericidal activity. Thus, we reveal how cagPAI-positive H. pylori strains use CagA to evade a key innate mucosal defense pathway to support the establishment of persistent infection.
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Affiliation(s)
- Bianca Bauer
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Charitéplatz 1, Berlin, Germany
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Yang YJ, Sheu BS. Probiotics-containing yogurts suppress Helicobacter pylori load and modify immune response and intestinal microbiota in the Helicobacter pylori-infected children. Helicobacter 2012; 17:297-304. [PMID: 22759330 DOI: 10.1111/j.1523-5378.2012.00941.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND The benefits of probiotics to the pediatric Helicobacter pylori infection remain uncertain. We tested whether the H. pylori-infected children have an altered gut microflora, and whether probiotics-containing yogurt can restore such change and improve their H. pylori-related immune cascades. METHODS We prospectively included 38 children with H. pylori infection confirmed by a positive ¹³C-urea breath test (UBT) and 38 age- and sex-matched noninfected controls. All of them have provided the serum and stool samples before and after 4-week ingestion of probiotics-containing yogurt. The serum samples were tested for the TNF-α, IL-10, IL-6, immunoglobulin (Ig) A, G, E, pepsinogens I and II levels. The stool samples were tested for the colony counts of Bifidobacterium spp. and Escherichia coli. The follow-up UBT indirectly assessed the H. pylori loads after yogurt usage. RESULTS The H. pylori-infected children had lower fecal Bifidobacterium spp. count (p = .009), Bifidobacterium spp./E. coli ratio (p = .04), serum IgA titer (p = .04), and pepsinogens I/II ratio (p < .001) than in controls. In the H. pylori-infected children, 4-week yogurt ingestion reduced the IL-6 level (p < .01) and H. pylori loads (p = .046), but elevated the serum IgA and pepsinogen II levels (p < .001). Moreover, yogurt ingestion can improve the childhood fecal Bifidobacterium spp./E. coli ratio (p = .03). CONCLUSIONS The H. pylori-infected children have a lower Bifidobacterium microflora in gut. The probiotics-containing yogurt can offer benefits to restore Bifidobacterium spp./E. coli ratio in children and suppress the H. pylori load with increment of serum IgA but with reduction in IL-6 in H. pylori-infected children.
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Affiliation(s)
- Yao-Jong Yang
- Department of Pediatrics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Schmitz JM, Durham CG, Schoeb TR, Soltau TD, Wolf KJ, Tanner SM, McCracken VJ, Lorenz RG. Helicobacter felis--associated gastric disease in microbiota-restricted mice. J Histochem Cytochem 2011; 59:826-41. [PMID: 21852692 PMCID: PMC3201166 DOI: 10.1369/0022155411416242] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Accepted: 06/13/2011] [Indexed: 12/23/2022] Open
Abstract
Human Helicobacter pylori infection leads to multiple pathological consequences, including gastritis and adenocarcinoma. Although this association has led to the classification of H. pylori as a type 1 carcinogen, it is not clear if additional nonhelicobacter gastric microbiota play a role in these diseases. In this study, we utilized either specific pathogen-free C57BL/6 mice (B6.SPF) or mice colonized with altered Schaedler flora (B6.ASF) to evaluate the role of nonhelicobacter gastric microbiota in disease development after Helicobacter felis infection. Despite similar histological changes, H. felis persisted in B6.ASF stomachs, while H. felis could no longer be detected in the majority of B6.SPF mice. The B6.SPF mice also acquired multiple Lactobacillus spp. in their stomachs after H. felis infection. Our data indicate that potential mechanisms responsible for the ineffective H. felis clearance in the B6.ASF model include the absence of new gastric microbiota to compete for the gastric niche, the lack of expression of new gastric mucins, and a reduced ratio of H. felis-specific IgG2c:IgG1 serum antibodies. These data suggest that although H. felis is sufficient to initiate gastric inflammation and atrophy, bacterial eradication and the systemic immune response to infection are significantly influenced by pre-existing and acquired gastric microbiota.
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Affiliation(s)
- Julia M. Schmitz
- Department of Medicine/CGIBD, University of North Carolina at Chapel Hill
| | | | | | | | | | | | - Vance J. McCracken
- Department of Biological Sciences, Southern Illinois University Edwardsville, IL
| | - Robin G. Lorenz
- Robin G. Lorenz, Department of Pathology, University of Alabama at Birmingham, 1825 University Boulevard, SHEL 602, Birmingham, AL 35294-2182. E-mail:
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Lofgren JL, Whary MT, Ge Z, Muthupalani S, Taylor NS, Mobley M, Potter A, Varro A, Eibach D, Suerbaum S, Wang TC, Fox JG. Lack of commensal flora in Helicobacter pylori-infected INS-GAS mice reduces gastritis and delays intraepithelial neoplasia. Gastroenterology 2011; 140:210-20. [PMID: 20950613 PMCID: PMC3006487 DOI: 10.1053/j.gastro.2010.09.048] [Citation(s) in RCA: 261] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 08/31/2010] [Accepted: 09/17/2010] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Transgenic FVB/N insulin-gastrin (INS-GAS) mice have high circulating gastrin levels, and develop spontaneous atrophic gastritis and gastrointestinal intraepithelial neoplasia (GIN) with 80% prevalence 6 months after Helicobacter pylori infection. GIN is associated with gastric atrophy and achlorhydria, predisposing mice to nonhelicobacter microbiota overgrowth. We determined if germfree INS-GAS mice spontaneously develop GIN and if H pylori accelerates GIN in gnotobiotic INS-GAS mice. METHODS We compared gastric lesions, levels of messenger RNA, serum inflammatory mediators, antibodies, and gastrin among germfree and H pylori-monoinfected INS-GAS mice. Microbiota composition of specific pathogen-free (SPF) INS-GAS mice was quantified by pyrosequencing. RESULTS Germfree INS-GAS mice had mild hypergastrinemia but did not develop significant gastric lesions until 9 months old and did not develop GIN through 13 months. H pylori monoassociation caused progressive gastritis, epithelial defects, oxyntic atrophy, marked foveolar hyperplasia, dysplasia, and robust serum and tissue proinflammatory immune responses (particularly males) between 5 and 11 months postinfection (P<0.05, compared with germfree controls). Only 2 of 26 female, whereas 8 of 18 male, H pylori-infected INS-GAS mice developed low to high-grade GIN by 11 months postinfection. Stomachs of H pylori-infected SPF male mice had significant reductions in Bacteroidetes and significant increases in Firmicutes. CONCLUSIONS Gastric lesions take 13 months longer to develop in germfree INS-GAS mice than male SPF INS-GAS mice. H pylori monoassociation accelerated gastritis and GIN but caused less severe gastric lesions and delayed onset of GIN compared with H pylori-infected INS-GAS mice with complex gastric microbiota. Changes in gastric microbiota composition might promote GIN in achlorhydric stomachs of SPF mice.
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Affiliation(s)
- Jennifer L. Lofgren
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Mark T. Whary
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Zhongming Ge
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Sureshkumar Muthupalani
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Nancy S. Taylor
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Melissa Mobley
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Amanda Potter
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Andrea Varro
- Physiological Laboratory, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Daniel Eibach
- Medizinische Hochschule Hannover, Institut für Medizinische Mikrobiologie und Krankenhaushygiene, D-30625 Hannover, Germany
| | - Sebastian Suerbaum
- Medizinische Hochschule Hannover, Institut für Medizinische Mikrobiologie und Krankenhaushygiene, D-30625 Hannover, Germany
| | - Timothy C. Wang
- Medizinische Hochschule Hannover, Institut für Medizinische Mikrobiologie und Krankenhaushygiene, D-30625 Hannover, Germany
| | - James G. Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139
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Sekirov I, Finlay BB. The role of the intestinal microbiota in enteric infection. J Physiol 2009; 587:4159-67. [PMID: 19491248 DOI: 10.1113/jphysiol.2009.172742] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The consortia of microorganisms inhabiting the length of the gastrointestinal tract, the gastrointestinal microbiota, are vital to many aspects of normal host physiology. In addition, they are an active participant in the progression of many diseases, among them enteric infections. Healthy intestinal microbiota contribute to host resistance to infection through their involvement in the development of the host immune system and provision of colonization resistance. It is not surprising then that disruptions of the microbial community translate into alterations of host susceptibility to infection. Additionally, the process of the infection itself results in a disturbance to the microbiota. This disturbance is often mediated by the host inflammatory response, allowing the pathogen to benefit from the inflammation at the intestinal mucosa. Uncovering the mechanisms underlying the host-pathogen-microbiota interactions will facilitate our understanding of the infection process and promote design of more effective and focused prophylactic and therapeutic strategies.
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Affiliation(s)
- Inna Sekirov
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
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Schmitz JM, Durham CG, Ho SB, Lorenz RG. Gastric mucus alterations associated with murine Helicobacter infection. J Histochem Cytochem 2009; 57:457-67. [PMID: 19153195 DOI: 10.1369/jhc.2009.952473] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The C57BL/6 mouse has been shown to develop gastric adenocarcinoma after Helicobacter felis infection. This model was used to determine whether mucin and trefoil factor (TFF) expression after infection was altered in a similar fashion to the changes seen in the protective gastric mucus layer of the human stomach after H. pylori infection. Our results indicate that this mouse model mimics many of the changes seen after human H. pylori infection, including increased expression of muc4 and muc5b and loss of muc5ac. These alterations in mucin expression occurred as early as 4 weeks postinfection, before the development of significant mucous metaplasia or gastric dysplasia. The decrease in muc5ac expression occurred only in the body of the stomach and was not secondary to the adaptive immune response to infection, because a similar decrease in expression was seen after infection of B6.Rag-1(-/-) mice, which lack B and T cells. Intriguingly, the increased expression of Muc4 and Muc5b in infected C57BL/6 mice was not seen in the infected B6.Rag-1(-/-) mice. Because B6.Rag-1(-/-) mice do not develop gastric pathology after H. felis infection, these findings point to the potential role of Muc4 and Muc5b in disease progression. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.
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Affiliation(s)
- Julia M Schmitz
- Department of Microbiology, University of Alabama at Birmingham, 1825 University Boulevard, SHEL 602, Birmingham, AL 35294-2182, USA
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The seroepidemiology of Helicobacter pylori infection in Australia. Int J Infect Dis 2008; 12:500-4. [PMID: 18400542 DOI: 10.1016/j.ijid.2008.01.011] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Revised: 01/25/2008] [Accepted: 01/25/2008] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Infection with Helicobacter pylori is common worldwide and a significant cause of upper gastrointestinal disease. Prevalence of this infection varies in different population groups internationally. Because of the invasiveness of specimen collection for bacteriologic diagnosis and the expense of tests such as labeled urea breath tests, serology is the most feasible means of determining the population epidemiology of H. pylori. The aim of this study was to describe the seroepidemiology of H. pylori infection in Australia. METHODS H. pylori-specific ELISA for the presence of IgG antibodies was performed on a representative sample of 2413 sera from Australia in 2002, using validated serosurveillance methods. RESULTS The overall seroprevalence of H. pylori infection in Australia was 15.1% in 2002, with no statistical difference between genders. Seropositivity rates increased progressively with age, ranging between 4.0% in the 1-4-year-olds and 23.3% in the 50-59-year-olds. CONCLUSIONS The prevalence of infection with H. pylori in Australia was lower than rates reported in other developed countries, at 15.4%. This study provides important baseline measurements for future preventive measures including vaccine research and development. Further studies to determine subgroups at higher risk of infection may help target the more susceptible populations.
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Lupp C, Robertson ML, Wickham ME, Sekirov I, Champion OL, Gaynor EC, Finlay BB. Host-mediated inflammation disrupts the intestinal microbiota and promotes the overgrowth of Enterobacteriaceae. Cell Host Microbe 2007; 2:119-29. [PMID: 18005726 DOI: 10.1016/j.chom.2007.06.010] [Citation(s) in RCA: 714] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2006] [Revised: 01/30/2007] [Accepted: 06/25/2007] [Indexed: 12/17/2022]
Abstract
While the normal microbiota has been implicated as a critical defense against invading pathogens, the impact of enteropathogenic infection and host inflammation on intestinal microbial communities has not been elucidated. Using mouse models of Citrobacter rodentium, which closely mimics human diarrheal pathogens inducing host intestinal inflammation, and Campylobacter jejuni infection, as well as chemically and genetically induced models of intestinal inflammation, we demonstrate that host-mediated inflammation in response to an infecting agent, a chemical trigger, or genetic predisposition markedly alters the colonic microbial community. While eliminating a subset of indigenous microbiota, host-mediated inflammation supported the growth of either the resident or introduced aerobic bacteria, particularly of the Enterobacteriaceae family. Further, assault by an enteropathogen and host-mediated inflammation combined to significantly reduce the total numbers of resident colonic bacteria. These findings underscore the importance of intestinal microbial ecosystems in infectious colitis and noninfectious intestinal inflammatory conditions, such as inflammatory bowel disease.
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Affiliation(s)
- Claudia Lupp
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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Aebischer T, Walduck A, Schroeder J, Wehrens A, Chijioke O, Schreiber S, Meyer TF. A vaccine against Helicobacter pylori: towards understanding the mechanism of protection. Int J Med Microbiol 2007; 298:161-8. [PMID: 17702653 DOI: 10.1016/j.ijmm.2007.07.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Helicobacter pylori infection remains a significant global public health problem. Vaccine development against this infection appears to be feasible but has not yet delivered its promise in clinical trials. Efforts to improve current vaccination strategies would greatly benefit from a better molecular understanding of the mechanism of protection. Here, we review recent developments in this field.
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Affiliation(s)
- Toni Aebischer
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Charité Platz 1, D-10117 Berlin, Germany
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Heimesaat MM, Fischer A, Siegmund B, Kupz A, Niebergall J, Fuchs D, Jahn HK, Freudenberg M, Loddenkemper C, Batra A, Lehr HA, Liesenfeld O, Blaut M, Göbel UB, Schumann RR, Bereswill S. Shift towards pro-inflammatory intestinal bacteria aggravates acute murine colitis via Toll-like receptors 2 and 4. PLoS One 2007; 2:e662. [PMID: 17653282 PMCID: PMC1914380 DOI: 10.1371/journal.pone.0000662] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2007] [Accepted: 06/22/2007] [Indexed: 12/31/2022] Open
Abstract
Background Gut bacteria trigger colitis in animal models and are suspected to aggravate inflammatory bowel diseases. We have recently reported that Escherichia coli accumulates in murine ileitis and exacerbates small intestinal inflammation via Toll-like receptor (TLR) signaling. Methodology and Principal Findings Because knowledge on shifts in the intestinal microflora during colitis is limited, we performed a global survey of the colon flora of C57BL/10 wild-type (wt), TLR2-/-, TLR4-/-, and TLR2/4-/- mice treated for seven days with 3.5% dextrane-sulfate-sodium (DSS). As compared to wt animals, TLR2-/-, TLR4-/-, and TLR2/4-/- mice displayed reduced macroscopic signs of acute colitis and the amelioration of inflammation was associated with reduced IFN-gamma levels in mesenteric lymph nodes, lower amounts of neutrophils, and less FOXP3-positive T-cells in the colon in situ. During acute colitis E. coli increased in wt and TLR-deficient mice (P<0.05), but the final numbers reached were significantly lower in TLR2-/-, TLR4-/- and TLR2/4-/- animals, as compared to wt controls (P<0.01). Concentrations of Bacteroides/ Prevotella spp., and enterococci did not increase during colitis, but their numbers were significantly reduced in the colon of DSS-treated TLR2/4-/- animals (P<0.01). Numbers of lactobacilli and clostridia remained unaffected by colitis, irrespective of the TLR-genotype of mice. Culture-independent molecular analyses confirmed the microflora shifts towards enterobacteria during colitis and showed that the gut flora composition was similar in both, healthy wt and TLR-deficient animals. Conclusions and Significance DSS-induced colitis is characterized by a shift in the intestinal microflora towards pro-inflammatory Gram-negative bacteria. Bacterial products exacerbate acute inflammation via TLR2- and TLR4-signaling and direct the recruitment of neutrophils and regulatory T-cells to intestinal sites. E. coli may serve as a biomarker for colitis severity and DSS-induced barrier damage seems to be a valuable model to further identify bacterial factors involved in maintaining intestinal homeostasis and to test therapeutic interventions based upon anti-TLR strategies.
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Affiliation(s)
- Markus M. Heimesaat
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - André Fischer
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Britta Siegmund
- Medizinische Klinik I, Charité - Universitätsmedizin Berlin, Campus-Benjamin-Franklin, Berlin, Germany
| | - Andreas Kupz
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Julia Niebergall
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - David Fuchs
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Hannah-Katharina Jahn
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | | | - Christoph Loddenkemper
- Institut für Pathologie, Charité-Universitätsmedizin Berlin, Campus-Benjamin-Franklin, Berlin, Germany
| | - Arvind Batra
- Medizinische Klinik I, Charité - Universitätsmedizin Berlin, Campus-Benjamin-Franklin, Berlin, Germany
| | - Hans-Anton Lehr
- Institut Universitaire de Pathologie, Centre Universitaire Hospitalier Vaudois, Lausanne, Switzerland
| | - Oliver Liesenfeld
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Michael Blaut
- Abteilung Gastrointestinale Mikrobiologie, Deutsches Institut für Ernährungsforschung, Potsdam-Rehbrücke, Nuthetal, Germany
| | - Ulf B. Göbel
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Ralf R. Schumann
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Stefan Bereswill
- Institut für Mikrobiologie und Hygiene, Charité - Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
- * To whom correspondence should be addressed. E-mail:
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Webb DC, Otczyk DC, Cripps AW. Investigation of the potential of a 48kDa protein as a vaccine candidate for infection against nontypable Haemophilus influenzae. Vaccine 2007; 25:4012-9. [PMID: 17379362 DOI: 10.1016/j.vaccine.2007.02.048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Revised: 02/13/2007] [Accepted: 02/16/2007] [Indexed: 11/16/2022]
Abstract
This study determined the conservation and protective efficacy of a 48 kDa nontypable Haemophilus influenzae (NTHi) protein (P48). This protein was highly conserved across the strains of NTHi examined and mucosal immunization with recombinant P48 (rP48) significantly reduced the numbers of viable NTHi recovered from the lung following challenge. rP48 induced predominantly an IgG2a antibody response that correlated with the reduction in the number of viable NTHi in the lung. These antibodies were not bactericidal against NTHi. The results suggest that P48 warrants further investigation as a vaccine component for NTHi disease.
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Affiliation(s)
- Dianne C Webb
- Division of Molecular Bioscience, The John Curtin School of Medical Research, Australian National University, P.O. Box 334, Canberra City, ACT 2601, Australia
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Tan MP, Kaparakis M, Galic M, Pedersen J, Pearse M, Wijburg OLC, Janssen PH, Strugnell RA. Chronic Helicobacter pylori infection does not significantly alter the microbiota of the murine stomach. Appl Environ Microbiol 2007; 73:1010-3. [PMID: 17142378 PMCID: PMC1800740 DOI: 10.1128/aem.01675-06] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Accepted: 11/20/2006] [Indexed: 12/12/2022] Open
Abstract
We examined the impact of Helicobacter pylori infection on the murine gastric microbiota by culture and terminal-restriction fragment length polymorphism and found that neither acute nor chronic H. pylori infection substantially affected the gastric microbial composition. Interestingly, the total H. pylori burden detected by real-time PCR was significantly higher than that revealed by viable counts, suggesting that the antigenic load sustaining H. pylori-induced gastritis could be considerably higher than previously believed.
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Affiliation(s)
- Mai Ping Tan
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Victoria 3010, Australia
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