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Stoeltje L, Luc JK, Haddad T, Schrankel CS. The roles of ABCB1/P-glycoprotein drug transporters in regulating gut microbes and inflammation: insights from animal models, old and new. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230074. [PMID: 38497255 PMCID: PMC10945405 DOI: 10.1098/rstb.2023.0074] [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: 09/20/2023] [Accepted: 02/13/2024] [Indexed: 03/19/2024] Open
Abstract
Commensal enteric bacteria have evolved systems that enable growth in the ecologic niche of the host gastrointestinal tract. Animals evolved parallel mechanisms to survive the constant exposure to bacteria and their metabolic by-products. We propose that drug transporters encompass a crucial system to managing the gut microbiome. Drug transporters are present in the apical surface of gut epithelia. They detoxify cells from small molecules and toxins (xenobiotics) in the lumen. Here, we review what is known about commensal structure in the absence of the transporter ABCB1/P-glycoprotein in mammalian models. Knockout or low-activity alleles of ABCB1 lead to dysbiosis, Crohn's disease and ulcerative colitis in mammals. However, the exact function of ABCB1 in these contexts remain unclear. We highlight emerging models-the zebrafish Danio rerio and sea urchin Lytechinus pictus-that are poised to help dissect the fundamental mechanisms of ATP-binding cassette (ABC) transporters in the tolerance of commensal and pathogenic communities in the gut. We and others hypothesize that ABCB1 plays a direct role in exporting inflammatory bacterial products from host epithelia. Interdisciplinary work in this research area will lend novel insight to the transporter-mediated pathways that impact microbiome community structure and accelerate the pathogenesis of inflammatory bowel disease when perturbed. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.
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Affiliation(s)
- Lauren Stoeltje
- Department of Biology, San Diego State University, 5500 Campanile Drive, Life Sciences North, Room 321, San Diego, CA 92182, USA
| | - Jenna K. Luc
- Department of Biology, San Diego State University, 5500 Campanile Drive, Life Sciences North, Room 321, San Diego, CA 92182, USA
| | - Timothaus Haddad
- Department of Biology, San Diego State University, 5500 Campanile Drive, Life Sciences North, Room 321, San Diego, CA 92182, USA
| | - Catherine S. Schrankel
- Department of Biology, San Diego State University, 5500 Campanile Drive, Life Sciences North, Room 321, San Diego, CA 92182, USA
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Seamons A, Staucean O, Snyder JM, Brabb T, Hsu CC, Paik J. ALDH1A Inhibition Suppresses Colitis and Alters α4β7 Integrin Expression on Activated T Cells in Mdr1a-/- Mice. Nutrients 2023; 15:3883. [PMID: 37764666 PMCID: PMC10536456 DOI: 10.3390/nu15183883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/29/2023] Open
Abstract
There are limited pharmacological treatment options for inflammatory bowel disease (IBD), and some of these options are expensive and administered by injection or infusion. Thus, new cheaper and easier (oral) treatment options are needed. ALDH1A enzymes produce retinoic acid that can affect intestinal diseases such as IBD by regulating immune cells in the gut. We previously demonstrated that an orally deliverable ALDH1A inhibitor, WIN 18,466, can suppress colitis in an acute mouse model of IBD. Here, we tested the efficacy of ALDH1A inhibition in a chronic mouse model of IBD. Mdr1a-/- mice were treated with a diet containing WIN 18,446 starting 1 week prior to inducing colitis by H. bilis inoculation. Treatment was continued until the study end point and colitis was monitored based on clinical symptoms and confirmed by histological analysis. Immune cell phenotypes in colon-draining lymph nodes (cMLN) were analyzed. WIN 18,446 treatment reduced clinical symptoms and improved histopathologic colitis scores. This was associated with decreased expression of the gut homing integrin, α4β7, on T cells in cMLN; increased expression of CD103, a protein associated with tissue-resident memory T cells; and changes in dendritic cells, plasmacytoid dendritic cells and B cells in inhibitor-treated mice. ALDH1A inhibition broadly influences immune cells during colitis and is a potential new target for IBD treatment. Future studies will be needed to determine the efficacy of ALDH1A inhibition on active colitis and to evaluate its relative efficacy in comparison to approved drugs.
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Affiliation(s)
| | | | | | | | | | - Jisun Paik
- Department of Comparative Medicine, University of Washington, Seattle, WA 98195, USA; (A.S.); (O.S.); (J.M.S.); (T.B.); (C.C.H.)
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Helicobacter bilis Contributes to the Occurrence of Inflammatory Bowel Disease by Inducing Host Immune Disorders. BIOMED RESEARCH INTERNATIONAL 2022; 2022:1837850. [PMID: 35983246 PMCID: PMC9381287 DOI: 10.1155/2022/1837850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 07/17/2022] [Accepted: 07/20/2022] [Indexed: 11/29/2022]
Abstract
Gut microbiota coevolve with humans to achieve a symbiotic relationship, which ultimately leads to physiological homeostasis. A variety of diseases can occur once this balance is disrupted. Helicobacter bilis (H. bilis) is an opportunistic pathogen in humans, triggering multiple diseases, including inflammatory bowel disease (IBD). IBD is a chronic immunologically mediated inflammation of the human gastrointestinal tract, and its occurrence is closely related to the gut microbiota. Several studies have demonstrated that H. bilis colonization is associated with IBD, and its mechanism is related to host immunity. However, few studies have investigated these mechanisms of action. Therefore, this article is aimed at reviewing these studies and summarizing the mechanisms of H. bilis-induced IBD from two perspectives: adaptive immunity and innate immunity. Furthermore, this study provides a preliminary discussion on treating H. bilis-related IBD. In addition, we also demonstrated that H. bilis played an important role in promoting the carcinogenesis of IBD and discussed its mechanism.
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Negi S, Saini S, Tandel N, Sahu K, Mishra RP, Tyagi RK. Translating Treg Therapy for Inflammatory Bowel Disease in Humanized Mice. Cells 2021; 10:cells10081847. [PMID: 34440615 PMCID: PMC8393385 DOI: 10.3390/cells10081847] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 02/07/2023] Open
Abstract
Crohn's disease and ulcerative colitis, two major forms of inflammatory bowel disease (IBD) in humans, afflicted in genetically predisposed individuals due to dysregulated immune response directed against constituents of gut flora. The defective immune responses mounted against the regulatory mechanisms amplify and maintain the IBD-induced mucosal inflammation. Therefore, restoring the balance between inflammatory and anti-inflammatory immunepathways in the gut may contribute to halting the IBD-associated tissue-damaging immune response. Phenotypic and functional characterization of various immune-suppressive T cells (regulatory T cells; Tregs) over the last decade has been used to optimize the procedures for in vitro expansion of these cells for developing therapeutic interventional strategies. In this paper, we review the mechanisms of action and functional importance of Tregs during the pathogenesis of IBD and modulating the disease induced inflammation as well as role of mouse models including humanized mice repopulated with the human immune system (HIS) to study the IBD. "Humanized" mouse models provide new tools to analyze human Treg ontogeny, immunobiology, and therapy and the role of Tregs in developing interventional strategies against IBD. Overall, humanized mouse models replicate the human conditions and prove a viable tool to study molecular functions of human Tregs to harness their therapeutic potential.
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MESH Headings
- Adoptive Transfer
- Animals
- Colitis, Ulcerative/genetics
- Colitis, Ulcerative/immunology
- Colitis, Ulcerative/metabolism
- Colitis, Ulcerative/therapy
- Crohn Disease/genetics
- Crohn Disease/immunology
- Crohn Disease/metabolism
- Crohn Disease/therapy
- Disease Models, Animal
- Hematopoietic Stem Cell Transplantation
- Humans
- Mice, Transgenic
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
- T-Lymphocytes, Regulatory/transplantation
- Transplantation, Heterologous
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Affiliation(s)
- Sushmita Negi
- Biomedical Parasitology and Nano-Immunology Lab, Division of Cell Biology and Immunology, CSIR-Institute of Microbial Technology (IMTECH), Chandigarh 160036, India; (S.N.); (S.S.); (K.S.)
- BERPDC Department, CSIR-Institute of Microbial Technology (IMTECH), Chandigarh 160036, India
| | - Sheetal Saini
- Biomedical Parasitology and Nano-Immunology Lab, Division of Cell Biology and Immunology, CSIR-Institute of Microbial Technology (IMTECH), Chandigarh 160036, India; (S.N.); (S.S.); (K.S.)
| | - Nikunj Tandel
- Institute of Science, Nirma University, Ahmedabad, Gujarat 382481, India;
| | - Kiran Sahu
- Biomedical Parasitology and Nano-Immunology Lab, Division of Cell Biology and Immunology, CSIR-Institute of Microbial Technology (IMTECH), Chandigarh 160036, India; (S.N.); (S.S.); (K.S.)
| | - Ravi P.N. Mishra
- BERPDC Department, CSIR-Institute of Microbial Technology (IMTECH), Chandigarh 160036, India
- Correspondence: (R.P.N.M.); or (R.K.T.)
| | - Rajeev K. Tyagi
- Biomedical Parasitology and Nano-Immunology Lab, Division of Cell Biology and Immunology, CSIR-Institute of Microbial Technology (IMTECH), Chandigarh 160036, India; (S.N.); (S.S.); (K.S.)
- Correspondence: (R.P.N.M.); or (R.K.T.)
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5
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Fleming TJ, Schrankel CS, Vyas H, Rosenblatt HD, Hamdoun A. CRISPR/Cas9 mutagenesis reveals a role for ABCB1 in gut immune responses to Vibrio diazotrophicus in sea urchin larvae. J Exp Biol 2021; 224:jeb232272. [PMID: 33653719 PMCID: PMC8077557 DOI: 10.1242/jeb.232272] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 02/08/2021] [Indexed: 12/16/2022]
Abstract
The ABC transporter ABCB1 plays an important role in the disposition of xenobiotics. Embryos of most species express high levels of this transporter in early development as a protective mechanism, but its native substrates are not known. Here, we used larvae of the sea urchin Strongylocentrotus purpuratus to characterize the early life expression and role of Sp-ABCB1a, a homolog of ABCB1. The results indicate that while Sp-ABCB1a is initially expressed ubiquitously, it becomes enriched in the developing gut. Using optimized CRISPR/Cas9 gene editing methods to achieve high editing efficiency in the F0 generation, we generated ABCB1a crispant embryos with significantly reduced transporter efflux activity. When infected with the opportunistic pathogen Vibrio diazotrophicus, Sp-ABCB1a crispant larvae demonstrated significantly stronger gut inflammation, immunocyte migration and cytokine Sp-IL-17 induction, as compared with infected control larvae. The results suggest an ancestral function of ABCB1 in host-microbial interactions, with implications for the survival of invertebrate larvae in the marine microbial environment.
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Affiliation(s)
- Travis J. Fleming
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
- Program in Biological and Biomedical Sciences, Harvard Medical School, Boston, MA 02115, USA
| | - Catherine S. Schrankel
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
| | - Himanshu Vyas
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
| | - Hannah D. Rosenblatt
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
| | - Amro Hamdoun
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA
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6
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Whary MT, Wang C, Ruff CF, DiVincenzo MJ, Labriola C, Ge L, Feng Y, Ge Z, Bakthavatchalu V, Muthupalani S, Horwitz BH, Fox JG. Effects of Colonization of Gnotobiotic Swiss Webster Mice with Helicobacter bilis. Comp Med 2020; 70:216-232. [PMID: 32349859 DOI: 10.30802/aalas-cm-19-000087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Helicobacter bilis (Hb) causes hepatitis in some strains of inbred mice. The current study confirmed that Hb directly causes portal hepatitis in outbred gnotobiotic Swiss Webster (SW) mice, as we previously reported for conventional SW mice. Hbmonoassociated SW mice also developed mild enterocolitis, expanded gut-associated lymphoid tissue (GALT), and tertiary lymphoid tissue in the lower bowel. At 1 and 10 mo after infection, Hb-induced GALT hyperplasia exhibited well-organized, ectopic germinal centers with increased mononuclear cell apoptosis, MHC class II antigen presentation, and pronounced endothelial venule formation, consistent with features of tertiary lymphoid tissue. In the lower bowel, Hb induced mainly B220+ cells as well as CD4+ IL17+, CD4+ IFNγ+, and CD4+ FoxP3+ regulatory T cells and significantly increased IL10 mRNA expression. This gnotobiotic model confirmed that Hb causes portal hepatitis in outbred SW mice but stimulated GALT with an antiinflammatory bias. Because Hb had both anti- and proinflammatory effects on GALT, it should be considered a 'pathosymbiont provocateur' and merits further evaluation in mouse models of human disease.
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Affiliation(s)
- Mark T Whary
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts;,
| | - Chuanwu Wang
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Catherine F Ruff
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Mallory J DiVincenzo
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Caralyn Labriola
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Lillian Ge
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Yan Feng
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Zhongming Ge
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Vasu Bakthavatchalu
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Suresh Muthupalani
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Bruce H Horwitz
- Department of Pediatrics, Harvard School of Medicine, Boston, Massachusetts; Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts
| | - James G Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, Massachusetts; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts
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7
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Espenschied ST, Cronan MR, Matty MA, Mueller O, Redinbo MR, Tobin DM, Rawls JF. Epithelial delamination is protective during pharmaceutical-induced enteropathy. Proc Natl Acad Sci U S A 2019; 116:16961-16970. [PMID: 31391308 PMCID: PMC6708343 DOI: 10.1073/pnas.1902596116] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intestinal epithelial cell (IEC) shedding is a fundamental response to intestinal damage, yet underlying mechanisms and functions have been difficult to define. Here we model chronic intestinal damage in zebrafish larvae using the nonsteroidal antiinflammatory drug (NSAID) Glafenine. Glafenine induced the unfolded protein response (UPR) and inflammatory pathways in IECs, leading to delamination. Glafenine-induced inflammation was augmented by microbial colonization and associated with changes in intestinal and environmental microbiotas. IEC shedding was a UPR-dependent protective response to Glafenine that restricts inflammation and promotes animal survival. Other NSAIDs did not induce IEC delamination; however, Glafenine also displays off-target inhibition of multidrug resistance (MDR) efflux pumps. We found a subset of MDR inhibitors also induced IEC delamination, implicating MDR efflux pumps as cellular targets underlying Glafenine-induced enteropathy. These results implicate IEC delamination as a protective UPR-mediated response to chemical injury, and uncover an essential role for MDR efflux pumps in intestinal homeostasis.
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Affiliation(s)
- Scott T Espenschied
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Mark R Cronan
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Molly A Matty
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Olaf Mueller
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Matthew R Redinbo
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Department of Biochemistry, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599
| | - David M Tobin
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710
- Department of Immunology, Duke University School of Medicine, Durham, NC 27710
| | - John F Rawls
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710;
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710
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8
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Paik J, Meeker S, Hsu CC, Seamons A, Pershutkina O, Snyder JM, Brabb T, Maggio-Price L. Validation studies for germ-free Smad3-/- mice as a bio-assay to test the causative role of fecal microbiomes in IBD. Gut Microbes 2019; 11:21-31. [PMID: 31138018 PMCID: PMC6973324 DOI: 10.1080/19490976.2019.1611151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
While the association between microbiomes and inflammatory bowel disease (IBD) is well known, establishing causal relationships between the two is difficult in humans. Germ-free (GF) mice genetically susceptible to IBD can address this question. Smad3-/- mice with defective transforming growth factor ß signaling are a model of IBD and colon cancer. They develop IBD upon colonization with Helicobacter under specific pathogen-free conditions, suggesting a role of the microbiome in IBD in this model. Thus, we rederived Smad3-/- mice GF to determine the potential of using these mice for testing the causative role of microbiomes in IBD. We found that fecal microbiomes from mice with IBD cause more severe gut inflammation in GF Smad3-/- and wild type mice compared to microbiomes from healthy mice and that Helicobacter induces gut inflammation within the context of other microbiomes but not by itself. Unexpectedly, GF Smad3+/+ and Smad3+/- mice given IBD microbiomes develop IBD despite their lack of disease in SPF conditions upon Helicobacter infection. This was not unique to the background strain of our Smad3 model (129); both wild type C57BL/6 and 129 strains developed IBD upon fecal transfer. However, wild type Swiss Webster stock was not susceptible, indicating that the genetic background of recipient mice influences the severity of IBD following fecal transfer. Our data suggest that the microbiome is an independent risk factor contributing to IBD development, and careful characterization of new GF models is needed to understand potential sources of confounding factors influencing microbiome studies in these mice.
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Affiliation(s)
- Jisun Paik
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA,CONTACT Jisun Paik The Department of Comparative Medicine, University of Washington, Seattle, WA 98195, USA
| | - Stacey Meeker
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Charlie C. Hsu
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Audrey Seamons
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Olesya Pershutkina
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Jessica M. Snyder
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Thea Brabb
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Lillian Maggio-Price
- The Department of Comparative Medicine, University of Washington, Seattle, WA, USA
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9
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ABC transporters Mdr1a/1b, Bcrp1, Mrp2 and Mrp3 determine the sensitivity to PhIP/DSS-induced colon carcinogenesis and inflammation. Arch Toxicol 2019; 93:775-790. [DOI: 10.1007/s00204-019-02394-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 01/10/2019] [Indexed: 12/29/2022]
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Mueller C, Kwong Chung CKC, Faderl MR, Brasseit J, Zysset D. Helicobacter spp. in Experimental Models of Colitis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1197:97-105. [DOI: 10.1007/978-3-030-28524-1_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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A gut pathobiont synergizes with the microbiota to instigate inflammatory disease marked by immunoreactivity against other symbionts but not itself. Sci Rep 2017; 7:17707. [PMID: 29255158 PMCID: PMC5735134 DOI: 10.1038/s41598-017-18014-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 12/05/2017] [Indexed: 12/11/2022] Open
Abstract
Inflammatory bowel diseases (IBD) are likely driven by aberrant immune responses directed against the resident microbiota. Although IBD is commonly associated with a dysbiotic microbiota enriched in putative pathobionts, the etiological agents of IBD remain unknown. Using a pathobiont-induced intestinal inflammation model and a defined bacterial community, we provide new insights into the immune-microbiota interactions during disease. In this model system, the pathobiont Helicobacter bilis instigates disease following sub-pathological dextran sulfate sodium treatment. We show that H. bilis causes mild inflammation in mono-associated mice, but severe disease in the presence of a microbiota, demonstrating synergy between the pathobiont and microbiota in exacerbating pathology. Remarkably, inflammation depends on the presence of H. bilis, but is marked by a predominant Th17 response against specific members of the microbiota and not the pathobiont, even upon the removal of the most immune-dominant taxa. Neither increases in pathobiont burden nor unique changes in immune-targeted microbiota member abundances are observed during disease. Collectively, our findings demonstrate that a pathobiont instigates inflammation without being the primary target of a Th17 response or by altering the microbiota community structure. Moreover, our findings point toward monitoring pathobiont-induced changes in microbiota immune targeting as a new concept in IBD diagnotics.
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12
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Cario E. P-glycoprotein multidrug transporter in inflammatory bowel diseases: More questions than answers. World J Gastroenterol 2017; 23:1513-1520. [PMID: 28321153 PMCID: PMC5340804 DOI: 10.3748/wjg.v23.i9.1513] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/06/2017] [Accepted: 02/17/2017] [Indexed: 02/06/2023] Open
Abstract
The gastrointestinal barrier is constantly exposed to numerous environmental substrates that are foreign and potentially harmful. These xenobiotics can cause shifts in the intestinal microbiota composition, affect mucosal immune responses, disturb tissue integrity and impair regeneration. The multidrug transporter ABCB1/MDR1 p-glycoprotein (p-gp) plays a key role at the front line of host defence by efficiently protecting the gastrointestinal barrier from xenobiotic accumulation. This Editorial discusses how altered expression and function of ABCB1/MDR1 p-gp may contribute to the development and persistence of chronic intestinal inflammation in inflammatory bowel diseases (IBD). Recent evidence implies multiple interactions between intestinal microbiota, innate immunity and xenobiotic metabolism via p-gp. While decreased efflux activity may promote disease susceptibility and drug toxicity, increased efflux activity may confer resistance to therapeutic drugs in IBD. Mice deficient in MDR1A develop spontaneously chronic colitis, providing a highly valuable murine IBD model for the study of intestinal epithelial barrier function, immunoregulation, infectious co-triggers and novel therapeutic approaches. Possible associations of human ABCB1 gene polymorphisms with IBD susceptibility have been evaluated, but results are inconsistent. Future studies must focus on further elucidation of the pathophysiological relevance and immunological functions of p-gp and how its ambiguous effects could be therapeutically targeted in IBD.
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13
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Helicobacter bilis Infection Alters Mucosal Bacteria and Modulates Colitis Development in Defined Microbiota Mice. Inflamm Bowel Dis 2016; 22:2571-2581. [PMID: 27755267 PMCID: PMC5123692 DOI: 10.1097/mib.0000000000000944] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Helicobacter bilis infection of C3H/HeN mice harboring the altered Schaedler flora (ASF) triggers progressive immune responsiveness and the development of colitis. We sought to investigate temporal alterations in community structure of a defined (ASF-colonized) microbiota in normal and inflamed murine intestines and to correlate microbiota changes to histopathologic lesions. METHODS The colonic mucosal microbiota of healthy mice and ASF mice colonized with H. bilis for 3, 6, or 12 weeks were investigated by fluorescence in situ hybridization targeting the 16S ribosomal RNA genes of total bacteria, group-specific organisms, and individual ASF bacterial species. Microbial profiling of ASF and H. bilis abundance was performed on cecal contents. RESULTS Helicobacter bilis-colonized mice developed colitis associated with temporal changes in composition and spatial distribution of the mucosal microbiota. The number of total bacteria, ASF519, and helicobacter-positive bacteria were increased (P < 0.05), whereas ASF360/361-positive bacteria were decreased (P < 0.05) versus controls. Adherent biofilms in colitic mice were most often (P < 0.05) composed of total bacteria, ASF457, and H. bilis. Total numbers of ASF519 and H. bilis bacteria were positively correlated (P = 0.03, r = 0.39 and P < 0.0001, r = 0.73), and total numbers of ASF360/361 bacteria were negatively correlated (P = 0.003, r = -0.53) to histopathologic score. Differences in cecal abundance of ASF members were not observed. CONCLUSIONS Altered community structure with murine colitis is characterized by distinct ASF bacteria that interact with the colonic mucosa, by formation of an isolating interlaced layer, by attachment, or by invasion, and this interaction is differentially expressed over time.
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14
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Shen Z, Feng Y, Muthupalani S, Sheh A, Cheaney LE, Kaufman CA, Gong G, Paster BJ, Fox JG. Novel Helicobacter species H.japonicum isolated from laboratory mice from Japan induces typhlocolitis and lower bowel carcinoma in C57BL/129 IL10-/- mice. Carcinogenesis 2016; 37:1190-1198. [PMID: 27655833 PMCID: PMC5137264 DOI: 10.1093/carcin/bgw101] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 08/29/2016] [Accepted: 09/20/2016] [Indexed: 12/28/2022] Open
Abstract
A novel Helicobacter species Helicobacter japonicum was isolated from the stomach and intestines of clinically normal mice received from three institutes from Japan. The novel Helicobacter sp. was microaerobic, grew at 37°C and 42°C, was catalase and oxidase positive, but urease negative. It is most closely related to the 16S rRNA gene of H.muridarum (98.6%); to the 23S rRNA gene of H.hepaticus (97.9%); to the hsp60 gene of H.typhlonius (87%). The novel Helicobacter sp. has in vitro cytolethal distending toxin (CDT) activity; its cdtB gene sequence has 83.8% identity with that of H.hepaticus The whole genome sequence of H.japonicum MIT 01-6451 has a 2.06-Mb genome length with a 37.5% G + C content. When the organism was inoculated into C57BL/129 IL10-/- mice, it was cultured from the stomach, colon and cecum of infected mice at 6 and 10 weeks post-infection. The cecum had the highest H.japonicum colonization levels by quantitative PCR. The histopathology of the lower bowel was characterized by moderate to severe inflammation, mild edema, epithelial defects, mild to severe hyperplasia, dysplasia and carcinoma. Inflammatory cytokines IFNγ, TNFα and IL17a, as well as iNOS were significantly upregulated in the cecal tissue of infected mice. These results demonstrate that the novel H.japonicum can induce inflammatory bowel disease and carcinoma in IL10-/- mice and highlights the importance of identifying novel Helicobacter spp. especially when they are introduced from outside mouse colonies from different geographic locations.
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Affiliation(s)
| | - Yan Feng
- Division of Comparative Medicine
| | | | | | | | | | - Guanyu Gong
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA and
| | | | - James G Fox
- Division of Comparative Medicine, .,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA and
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Barnett MPG, Dommels YEM, Butts CA, Zhu S, McNabb WC, Roy NC. Inoculation with enterococci does not affect colon inflammation in the multi-drug resistance 1a-deficient mouse model of IBD. BMC Gastroenterol 2016; 16:31. [PMID: 26940566 PMCID: PMC4778357 DOI: 10.1186/s12876-016-0447-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 02/24/2016] [Indexed: 01/08/2023] Open
Abstract
Background Intestinal bacteria are thought to play a role in the pathogenesis of human inflammatory bowel disease (IBD). We investigated whether oral inoculation with specific intestinal bacteria increased colon inflammation in the multi-drug resistance 1a-deficient (Mdr1a–/–) mouse model of IBD. Methods Five-week-old Mdr1a–/– mice (FVB background) and FVB mice were randomly assigned to one of two treatment groups (Control or Inoculation, n = 12 per group). All mice were fed AIN-76A rodent diet, and mice in the Inoculation groups also received a single oral bacterial inoculation consisting of twelve cultured Enterococcus species combined with conventional intestinal flora obtained from the gastrointestinal tract of healthy mice (EF.CIF). Body weight, food intake, and disease activity index (DAI) were assessed throughout the study, and at 21 or 24 weeks of age, inflammation was assessed post-mortem by determining colon length and histological injury score (HIS), and plasma serum amyloid A (SAA). Results Mdr1a–/– mice consumed more food than FVB mice at 13 weeks of age (P < 0.05). There was also a significant effect of genotype on body weight, with Mdr1a–/– mice weighing less than FVB mice throughout the study (P < 0.05) regardless of treatment, but there was no effect of inoculation on body weight (P > 0.25). Colon HIS of Mdr1a–/– mice was significantly higher than that of FVB mice in the Control (9.3 ± 4.7 (mean ± SD) vs. 0.58 ± 0.51; P < 0.001) and Inoculation (6.7 ± 5.1 vs. 0.92 ± 0.39; P < 0.001) groups. There was no difference in colon HIS of Mdr1a–/– mice in the Control group compared with Mdr1a–/– mice in the Inoculation group (P = 0.25), nor was there any difference in within-group variation of colon HIS in these two Mdr1a–/– groups. DAI was higher in Mdr1a–/– mice than in FVB mice, but there was no effect of treatment in either strain, nor were there any differences in colon length or plasma SAA. Conclusions Inoculation of Mdr1a–/– mice with the EF.CIF inoculum described here does not increase colon inflammation or reduce the observed variability of inflammation. Electronic supplementary material The online version of this article (doi:10.1186/s12876-016-0447-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Matthew P G Barnett
- Food Nutrition & Health Team, Food & Bio-based Products Group, AgResearch, Palmerston North, 4474, New Zealand. .,Gravida: National Centre for Growth and Development, Private Bag 92019, Auckland, 1142, New Zealand.
| | - Yvonne E M Dommels
- Food and Nutrition, Food Innovation, Plant & Food Research, Palmerston North, 4474, New Zealand.
| | - Christine A Butts
- Food and Nutrition, Food Innovation, Plant & Food Research, Palmerston North, 4474, New Zealand.
| | - Shuotun Zhu
- Discipline of Nutrition, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, 1023, New Zealand.
| | - Warren C McNabb
- AgResearch, Palmerston North, 4474, New Zealand. .,Riddet Institute, Massey University, Palmerston North, 4474, New Zealand.
| | - Nicole C Roy
- Food Nutrition & Health Team, Food & Bio-based Products Group, AgResearch, Palmerston North, 4474, New Zealand. .,Gravida: National Centre for Growth and Development, Private Bag 92019, Auckland, 1142, New Zealand. .,Riddet Institute, Massey University, Palmerston North, 4474, New Zealand.
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Yamada A, Arakaki R, Saito M, Tsunematsu T, Kudo Y, Ishimaru N. Role of regulatory T cell in the pathogenesis of inflammatory bowel disease. World J Gastroenterol 2016; 22:2195-205. [PMID: 26900284 PMCID: PMC4734996 DOI: 10.3748/wjg.v22.i7.2195] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 11/11/2015] [Accepted: 12/08/2015] [Indexed: 02/06/2023] Open
Abstract
Regulatory T (Treg) cells play key roles in various immune responses. For example, Treg cells contribute to the complex pathogenesis of inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis during onset or development of that disease. Many animal models of IBD have been used to investigate factors such as pathogenic cytokines, pathogenic bacteria, and T-cell functions, including those of Treg cells. In addition, analyses of patients with IBD facilitate our understanding of the precise mechanism of IBD. This review article focuses on the role of Treg cells and outlines the pathogenesis and therapeutic strategies of IBD based on previous reports.
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Cipe G, Idiz UO, Firat D, Bektasoglu H. Relationship between intestinal microbiota and colorectal cancer. World J Gastrointest Oncol 2015; 7:233-240. [PMID: 26483877 PMCID: PMC4606177 DOI: 10.4251/wjgo.v7.i10.233] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 08/02/2015] [Accepted: 09/08/2015] [Indexed: 02/05/2023] Open
Abstract
The human gastrointestinal tract hosts a complex and vast microbial community with up to 1011-1012 microorganisms colonizing the colon. The gut microbiota has a serious effect on homeostasis and pathogenesis through a number of mechanisms. In recent years, the relationship between the intestinal microbiota and sporadic colorectal cancer has attracted much scientific interest. Mechanisms underlying colonic carcinogenesis include the conversion of procarcinogenic diet-related factors to carcinogens and the stimulation of procarcinogenic signaling pathways in luminal epithelial cells. Understanding each of these mechanisms will facilitate future studies, leading to the development of novel strategies for the diagnosis, treatment, and prevention of colorectal cancer. In this review, we discuss the relationship between colorectal cancer and the intestinal microbiota.
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Maxwell JR, Zhang Y, Brown WA, Smith CL, Byrne FR, Fiorino M, Stevens E, Bigler J, Davis JA, Rottman JB, Budelsky AL, Symons A, Towne JE. Differential Roles for Interleukin-23 and Interleukin-17 in Intestinal Immunoregulation. Immunity 2015; 43:739-50. [PMID: 26431947 DOI: 10.1016/j.immuni.2015.08.019] [Citation(s) in RCA: 251] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 06/28/2015] [Accepted: 08/20/2015] [Indexed: 12/12/2022]
Abstract
Interleukin-23 (IL-23) and IL-17 are cytokines currently being targeted in clinical trials. Although inhibition of both of these cytokines is effective for treating psoriasis, IL-12 and IL-23 p40 inhibition attenuates Crohn's disease, whereas IL-17A or IL-17 receptor A (IL-17RA) inhibition exacerbates Crohn's disease. This dichotomy between IL-23 and IL-17 was effectively modeled in the multidrug resistance-1a-ablated (Abcb1a(-/-)) mouse model of colitis. IL-23 inhibition attenuated disease by decreasing colonic inflammation while enhancing regulatory T (Treg) cell accumulation. Exacerbation of colitis by IL-17A or IL-17RA inhibition was associated with severe weakening of the intestinal epithelial barrier, culminating in increased colonic inflammation and accelerated mortality. These data show that IL-17A acts on intestinal epithelium to promote barrier function and provide insight into mechanisms underlying exacerbation of Crohn's disease when IL-17A or IL-17RA is inhibited.
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Affiliation(s)
- Joseph R Maxwell
- Department of Inflammation, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - Yu Zhang
- Department of Inflammation, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - William A Brown
- Department of Inflammation, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - Carole L Smith
- Department of Inflammation, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - Fergus R Byrne
- Department of Inflammation, Amgen, Inc., One Amgen Center Drive, Thousand Oaks, CA 91320, USA
| | - Mike Fiorino
- Department of Inflammation, Amgen, Inc., One Amgen Center Drive, Thousand Oaks, CA 91320, USA
| | - Erin Stevens
- Department of Clinical Immunology, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - Jeannette Bigler
- Department of Molecular Sciences and Computational Biology, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - John A Davis
- Department of Pharmacokinetics and Drug Metabolism, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - James B Rottman
- Department of Pathology, Amgen, Inc., 360 Binney Street, Cambridge, MA 02142, USA
| | - Alison L Budelsky
- Department of Inflammation, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - Antony Symons
- Department of Inflammation, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA
| | - Jennifer E Towne
- Department of Inflammation, Amgen, Inc., 1201 Amgen Court West, Seattle, WA 98117, USA.
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Abstract
Today’s laboratory mouse, Mus musculus, has its origins as the ‘house mouse’ of North America and Europe. Beginning with mice bred by mouse fanciers, laboratory stocks (outbred) derived from M. musculus musculus from eastern Europe and M. m. domesticus from western Europe were developed into inbred strains. Since the mid-1980s, additional strains have been developed from Asian mice (M. m. castaneus from Thailand and M. m. molossinus from Japan) and from M. spretus which originated from the western Mediterranean region.
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Cook LC, Hillhouse AE, Myles MH, Lubahn DB, Bryda EC, Davis JW, Franklin CL. The role of estrogen signaling in a mouse model of inflammatory bowel disease: a Helicobacter hepaticus model. PLoS One 2014; 9:e94209. [PMID: 24709804 PMCID: PMC3978010 DOI: 10.1371/journal.pone.0094209] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 03/13/2014] [Indexed: 12/23/2022] Open
Abstract
The pathogenesis of inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis, is due in part to interactions between the immune system, genetics, the environment, and endogenous microbiota. Gonadal sex hormones (GSH), such as estrogen, are thought to be involved in the development of IBD as variations in disease severity occur during pregnancy, menopause, or oral contraceptives use. In certain strains of mice, infection with Helicobacter hepaticus triggers IBD-like mucosal inflammation that is more severe in female mice than in males, suggesting a role for GSH in this model. To determine the role of estrogen signaling in microbiota-induced intestinal inflammation, estrogen receptor (ER) α and β knock-out (KO) mice, ER agonists, and adoptive transfers were utilized. We demonstrate that, when signaling is limited to ERβ on a non-CD4+ cell subset, disease is less severe and this correlates with decreased expression of pro-inflammatory mediators.
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Affiliation(s)
- Lydia C. Cook
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
| | - Andrew E. Hillhouse
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
- Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, Missouri, United States of America
| | - Matthew H. Myles
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
- IDEXX Laboratories, Columbia, Missouri, United States of America
| | - Dennis B. Lubahn
- Department of Biochemistry, University of Missouri, Columbia, Missouri, United States of America
| | - Elizabeth C. Bryda
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
| | - J. Wade Davis
- Departments of Health Management and Informatics, and Statistics, University of Missouri, Columbia, Missouri, United States of America
| | - Craig L. Franklin
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
- * E-mail:
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Bhardwaj EK, Else KJ, Rogan MT, Warhurst G. Increased susceptibility to Trichuris muris infection and exacerbation of colitis in Mdr1a-/- mice. World J Gastroenterol 2014; 20:1797-1806. [PMID: 24587657 PMCID: PMC3930978 DOI: 10.3748/wjg.v20.i7.1797] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 10/12/2013] [Accepted: 11/19/2013] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the influence of Trichuris muris (T. muris) infection in a mouse model of genetic susceptibility to inflammatory bowel disease, Mdr1a-/-.
METHODS: Mdr1a-/- mice were housed under specific pathogen free conditions to slow the development of colitis and compared to congenic FVB controls. Mice were infected with approximately 200 embryonated ova from T. muris and assessed for worm burden and histological and functional markers of gut inflammation on day 19 post infection.
RESULTS: Mdr1a-/- mice exhibited a marked increase in susceptibility to T. muris infection with a 10-fold increase in colonic worm count by day 19 pi compared to FVB controls. Prior to infection, Mdr1a-/- exhibited low-level mucosal inflammation with evidence of an enhanced Th1 environment. T. muris infection accelerated the progression of colitis in Mdr1a-/- as evidenced by marked increases in several indicators including histological damage score, mucosal CD4+ T-cell and DC infiltration and dramatically increased production of pro-inflammatory cytokines.
CONCLUSION: These data provide further evidence of the complex interaction between T. muris and an inflammatory bowel disease (IBD)-susceptible host which may have relevance to the application of helminth therapy in the treatment of human IBD.
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Abstract
BACKGROUND Wiskott-Aldrich syndrome protein-deficient patients and mice are immunodeficient and can develop inflammatory bowel disease. The intestinal microbiome is critical to the development of colitis in most animal models, in which Helicobacter spp. have been implicated in disease pathogenesis. We sought to determine the role of Helicobacter spp. in colitis development in Wiskott-Aldrich syndrome protein-deficient (WKO) mice. METHODS Feces from WKO mice raised under specific pathogen-free conditions were evaluated for the presence of Helicobacter spp., after which a subset of mice were rederived in Helicobacter spp.-free conditions. Helicobacter spp.-free WKO animals were subsequently infected with Helicobacter bilis. RESULTS Helicobacter spp. were detected in feces from WKO mice. After rederivation in Helicobacter spp.-free conditions, WKO mice did not develop spontaneous colitis but were susceptible to radiation-induced colitis. Moreover, a T-cell transfer model of colitis dependent on Wiskott-Aldrich syndrome protein-deficient innate immune cells also required Helicobacter spp. colonization. Helicobacter bilis infection of rederived WKO mice led to typhlitis and colitis. Most notably, several H. bilis-infected animals developed dysplasia with 10% demonstrating colon carcinoma, which was not observed in uninfected controls. CONCLUSIONS Spontaneous and T-cell transfer, but not radiation-induced, colitis in WKO mice is dependent on the presence of Helicobacter spp. Furthermore, H. bilis infection is sufficient to induce typhlocolitis and colon cancer in Helicobacter spp.-free WKO mice. This animal model of a human immunodeficiency with chronic colitis and increased risk of colon cancer parallels what is seen in human colitis and implicates specific microbial constituents in promoting immune dysregulation in the intestinal mucosa.
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Paik J, Fierce Y, Treuting PM, Brabb T, Maggio-Price L. High-fat diet-induced obesity exacerbates inflammatory bowel disease in genetically susceptible Mdr1a-/- male mice. J Nutr 2013; 143:1240-7. [PMID: 23761644 DOI: 10.3945/jn.113.174615] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Obesity is a chronic inflammatory disease and a risk factor for disorders such as heart disease, diabetes, and cancer. A high-fat diet (HFD), a risk factor for obesity, has also been associated with inflammatory bowel disease (IBD). A proinflammatory state characterized by systemic and local increases in cytokine and chemokine levels are noted in both obesity and IBD, but it is unclear whether obesity is a risk factor for IBD. To examine any association between obesity and IBD, we chose FVB.129P2- Abcb1a(tm1Bor)N7 (Mdr1a(-/-)) mice, because this strain develops IBD spontaneously with age without a chemical or bacterial "trigger." In addition, its background strain, FVB, has been used for diet-induced obesity studies. Mdr1a(-/-) mice and wild-type (WT) mice were fed a HFD (∼60% calories from fat) or a low-fat diet (LFD; ∼11% calories from fat) for 12 wk. Obesity phenotypes examined included body weight measurements, glucose metabolism changes, and adiposity at termination of the study. IBD was determined by clinical signs, necropsy, and histopathology. We found that compared with those fed the LFD, both the Mdr1a(-/-) and WT mice fed the HFD had greater weight gains and elevated plasma leptin concentrations (P < 0.0001). When all mice were analyzed, weight gain was also associated with inflammation in mesenteric fat (R(2) = 0.5; P < 0.0001) and mesenteric lymph nodes (R(2) = 0.4; P < 0.0001). In contrast, the HFD was not associated with IBD in WT mice, whereas it exacerbated spontaneous IBD in Mdr1a(-/-) mice (P = 0.012; Fisher's exact test). Although a HFD and obesity were not associated with IBD in WT mice, our studies suggest that they are likely risk factors for IBD in a genetically susceptible host, such as Mdr1a(-/-) mice.
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Affiliation(s)
- Jisun Paik
- Department of Comparative Medicine, and Nutritional Sciences Program, University of Washington, Seattle, WA, USA.
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Baliga MS, Joseph N, Venkataranganna MV, Saxena A, Ponemone V, Fayad R. Curcumin, an active component of turmeric in the prevention and treatment of ulcerative colitis: preclinical and clinical observations. Food Funct 2013; 3:1109-17. [PMID: 22833299 DOI: 10.1039/c2fo30097d] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Inflammatory bowel disease (IBD) comprising of ulcerative colitis (UC) and Crohn's disease (CD) is a major ailment affecting the small and large bowel. In clinics, IBD is treated using 5-amninosalicylates, antibiotics, the steroids and immunomodulators. Unfortunately, the long term usages of these agents are associated with undue side effects and compromise the therapeutic advantage. Accordingly, there is a need for novel agents that are effective, acceptable and non toxic to humans. Preclinical studies in experimental animals have shown that curcumin, an active principle of the Indian spice turmeric (Curcuma longa Linn) is effective in preventing or ameliorating UC and inflammation. Over the last few decades there has been increasing interest in the possible role of curcumin in IBD and several studies with various experimental models of IBD have shown it to be effective in mediating the inhibitory effects by scavenging free radicals, increasing antioxidants, influencing multiple signaling pathways, especially the kinases (MAPK, ERK), inhibiting myeloperoxidase, COX-1, COX-2, LOX, TNF-α, IFN-γ, iNOS; inhibiting the transcription factor NF-κB. Clinical studies have also shown that co-administration of curcumin with conventional drugs was effective, to be well-tolerated and treated as a safe medication for maintaining remission, to prevent relapse and improve clinical activity index. Large randomized controlled clinical investigations are required to fully understand the potential of oral curcumin for treating IBD.
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Affiliation(s)
- Manjeshwar Shrinath Baliga
- Department of Research and Development, Father Muller Medical College, Kankanady, Mangalore, Karnataka, India.
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Saksena S, Priyamvada S, Kumar A, Akhtar M, Soni V, Anbazhagan AN, Alakkam A, Alrefai WA, Dudeja PK, Gill RK. Keratinocyte growth factor-2 stimulates P-glycoprotein expression and function in intestinal epithelial cells. Am J Physiol Gastrointest Liver Physiol 2013; 304:G615-22. [PMID: 23328208 PMCID: PMC3602685 DOI: 10.1152/ajpgi.00445.2012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Intestinal P-glycoprotein (Pgp/multidrug resistance 1), encoded by the ATP-binding cassette B1 gene, is primarily involved in the transepithelial efflux of toxic metabolites and xenobiotics from the mucosa into the gut lumen. Reduced Pgp function and expression has been shown to be associated with intestinal inflammatory disorders. Keratinocyte growth factor-2 (KGF2) has emerged as a potential target for modulation of intestinal inflammation and maintenance of gut mucosal integrity. Whether KGF2 directly regulates Pgp in the human intestine is not known. Therefore, the present studies were undertaken to determine the modulation of Pgp by KGF2 using Caco-2 cells. Short-term treatment of Caco-2 cells with KGF2 (10 ng/ml, 1 h) increased Pgp activity (~2-fold, P < 0.05) as measured by verapamil-sensitive [(3)H]digoxin flux. This increase in Pgp function was associated with an increase in surface Pgp levels. The specific fibroblast growth factor receptor (FGFR) antagonist PD-161570 blocked the KGF2-mediated increase in Pgp activity. Inhibition of the mitogen-activated protein kinase (MAPK) pathway by PD-98059 attenuated the stimulatory effects of KGF2 on Pgp activity. Small-interfering RNA knockdown of Erk1/2 MAPK blocked the increase in surface Pgp levels by KGF2. Long-term treatment with KGF2 (10 ng/ml, 24 h) also significantly increased PgP activity, mRNA, protein expression, and promoter activity. The long-term effects of KGF2 on Pgp promoter activity were also blocked by the FGFR antagonist and mediated by the Erk1/2 MAPK pathway. In conclusion, our findings define the posttranslational and transcriptional mechanisms underlying stimulation of Pgp function and expression by KGF2 that may contribute to the beneficial effects of KGF2 in intestinal inflammatory disorders.
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Affiliation(s)
- Seema Saksena
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
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The Role of Bacteria in Cancer Development. Infect Agent Cancer 2013. [DOI: 10.1007/978-94-007-5955-8_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Baine I, Basu S, Ames R, Sellers RS, Macian F. Helios induces epigenetic silencing of IL2 gene expression in regulatory T cells. THE JOURNAL OF IMMUNOLOGY 2012; 190:1008-16. [PMID: 23275607 DOI: 10.4049/jimmunol.1200792] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Regulatory T cells (Tregs) play a critical role in maintaining immune tolerance and preventing autoimmune disease. Tregs express the transcription factor Foxp3, which acts as a master regulator of their differentiation and controls their capacity to suppress T cell responses. Tregs have an intrinsically anergic phenotype and do not produce IL-2 or proliferate upon stimulation ex vivo. Recent studies identified that Helios, a member of the Ikaros family of transcription factors, is expressed in Tregs. However, its specific function is not fully understood. In this study, we show that Helios regulates IL-2 production in Tregs by suppressing Il2 gene transcription. Loss of Helios in Tregs breaks their anergic phenotype and results in derepression of the Il2 locus, allowing Tregs to display increased baseline proliferation and to produce IL-2 following stimulation. Conversely, forced expression of Helios in CD4(+)Foxp3(-) T cells results in a loss of their normal ability to produce IL-2. Helios acts by binding to the Il2 promoter and inducing epigenetic modifications that include histone deacetylation. We also show that loss of Helios in Tregs results in decreased Foxp3 binding to the Il2 promoter, indicating that Helios promotes binding of Foxp3 to the Il2 promoter. Interestingly, the loss of Helios in Tregs also causes a decrease in suppressive capacity. Our results identify Helios as a key regulator of Il2 expression in Tregs, contributing to the maintenance of the anergic phenotype.
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Affiliation(s)
- Ian Baine
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Hu LL, Yu B, Yang J. MDR1polymorphisms associated with risk and survival in diffuse large B-cell lymphoma. Leuk Lymphoma 2012; 54:1188-93. [DOI: 10.3109/10428194.2012.736980] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Willis CR, Seamons A, Maxwell J, Treuting PM, Nelson L, Chen G, Phelps S, Smith CL, Brabb T, Iritani BM, Maggio-Price L. Interleukin-7 receptor blockade suppresses adaptive and innate inflammatory responses in experimental colitis. JOURNAL OF INFLAMMATION-LONDON 2012; 9:39. [PMID: 23057802 PMCID: PMC3551718 DOI: 10.1186/1476-9255-9-39] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 09/17/2012] [Indexed: 11/26/2022]
Abstract
Background Interleukin-7 (IL-7) acts primarily on T cells to promote their differentiation, survival, and homeostasis. Under disease conditions, IL-7 mediates inflammation through several mechanisms and cell types. In humans, IL-7 and its receptor (IL-7R) are increased in diseases characterized by inflammation such as atherosclerosis, rheumatoid arthritis, psoriasis, multiple sclerosis, and inflammatory bowel disease. In mice, overexpression of IL-7 results in chronic colitis, and T-cell adoptive transfer studies suggest that memory T cells expressing high amounts of IL-7R drive colitis and are maintained and expanded with IL-7. The studies presented here were undertaken to better understand the contribution of IL-7R in inflammatory bowel disease in which colitis was induced with a bacterial trigger rather than with adoptive transfer. Methods We examined the contribution of IL-7R on inflammation and disease development in two models of experimental colitis: Helicobacter bilis (Hb)-induced colitis in immune-sufficient Mdr1a−/− mice and in T- and B-cell-deficient Rag2−/− mice. We used pharmacological blockade of IL-7R to understand the mechanisms involved in IL-7R-mediated inflammatory bowel disease by analyzing immune cell profiles, circulating and colon proteins, and colon gene expression. Results Treatment of mice with an anti-IL-7R antibody was effective in reducing colitis in Hb-infected Mdr1a−/− mice by reducing T-cell numbers as well as T-cell function. Down regulation of the innate immune response was also detected in Hb-infected Mdr1a−/− mice treated with an anti-IL-7R antibody. In Rag2−/− mice where colitis was triggered by Hb-infection, treatment with an anti-IL-7R antibody controlled innate inflammatory responses by reducing macrophage and dendritic cell numbers and their activity. Conclusions Results from our studies showed that inhibition of IL-7R successfully ameliorated inflammation and disease development in Hb-infected mice by controlling the expansion of multiple leukocyte populations, as well as the activity of these immune cells. Our findings demonstrate an important function of IL-7R-driven immunity in experimental colitis and indicate that the therapeutic efficacy of IL-7R blockade involves affecting both adaptive and innate immunity.
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Affiliation(s)
| | - Audrey Seamons
- Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Joe Maxwell
- Department of Inflammation, Amgen, Inc, Seattle, WA, USA
| | - Piper M Treuting
- Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Laurel Nelson
- Department of Inflammation, Amgen, Inc, Seattle, WA, USA
| | - Guang Chen
- Department of Inflammation, Amgen, Inc, Seattle, WA, USA
| | - Susan Phelps
- Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Carole L Smith
- Department of Inflammation, Amgen, Inc, Seattle, WA, USA
| | - Thea Brabb
- Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Brian M Iritani
- Department of Comparative Medicine, University of Washington, Seattle, WA, USA.,Fred Hutchinson Cancer Research Center, Seattle, WA, USA
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Schoeb TR, Bullard DC. Microbial and histopathologic considerations in the use of mouse models of inflammatory bowel diseases. Inflamm Bowel Dis 2012; 18:1558-65. [PMID: 22294506 PMCID: PMC3733552 DOI: 10.1002/ibd.22892] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 01/04/2012] [Indexed: 12/14/2022]
Abstract
Mouse models provide powerful tools to investigate disease mechanisms and are widely used in inflammatory bowel disease research. However, it is common for reports of mouse model studies to lack potentially important information about the microbial status of the mice and the method used to evaluate disease expression for statistical analysis. For example, it is common practice to state that the mice were housed under specific pathogen-free conditions but provide no further information regarding the presence or absence of organisms such as Helicobacter spp. that are known or likely to affect disease expression, thus omitting information potentially important to the expected phenotype of the mice and their responses to experimental manipulation. We therefore encourage authors to use such terms as "conventional" and "specific pathogen-free" precisely, to state the agents from which the mice are represented to be free, and to provide a brief description of the health monitoring protocol. Descriptions of histopathologic methods used to evaluate colitis in mouse models also often do not include sufficient detail to allow readers to understand and evaluate the methods; in addition, the lesions commonly are shown in photomicrographs that are too small and of too low resolution to be interpreted. Inasmuch as such methods are often the major or only source of data upon which conclusions regarding genotype or experimental treatment effects are based, the method employed should be fully described, and photomicrographs should be of adequate size and resolution to allow independent assessment.
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Affiliation(s)
- Trenton R. Schoeb
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama
| | - Daniel C. Bullard
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama
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Lofgren JLS, Esmail M, Mobley M, McCabe A, Taylor NS, Shen Z, Erdman S, Hewes C, Whary MT, Fox JG. Prevalence of murine Helicobacter spp. Infection is reduced by restocking research colonies with Helicobacter-free mice. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2012; 51:436-442. [PMID: 23043808 PMCID: PMC3400691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 08/24/2011] [Accepted: 12/09/2011] [Indexed: 06/01/2023]
Abstract
Most academic research colonies of mice are endemically infected with enterohepatic Helicobacter spp. (EHS). We evaluated EHS prevalence in surveillance mice before and after a 10-y period of requiring that imported mice be free of EHS by embryo transfer rederivation or purchase from approved vendors. In 2009, composite fecal samples from CD1 surveillance mice representing colony health in 57 rooms located in 6 facilities were evaluated for EHS infection by using PCR assays. Fecal samples were screened with primers designed to detect all known EHS, and positive samples were further assayed by using primers specific for H. hepaticus, H. bilis, H. rodentium, and H. typhlonicus. Most EHS were detected in surveillance mice within the first month of dirty bedding exposure, with prevalence ranging from 0% to 64% as monoinfections or, more commonly, infections with multiple EHS. Compared with 1999 prevalence data, EHS remained endemic in colonies importing the lowest number of EHS-free mice. EHS were absent or the prevalence was greatly reduced in colonies receiving the highest percentage of EHS-free mice. This study demonstrates that the management decision to require exclusive importation of EHS-free mice reduced EHS prevalence on an institutional scale without intensive labor and expense associated with other techniques or interference with research objectives.
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Maxwell JR, Viney JL. Overview of mouse models of inflammatory bowel disease and their use in drug discovery. ACTA ACUST UNITED AC 2012; Chapter 5:Unit5.57. [PMID: 22294403 DOI: 10.1002/0471141755.ph0557s47] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Inflammatory bowel disease (IBD), a condition that affects millions of individuals, encompasses two distinct conditions: Crohn's disease (CD) and ulcerative colitis (UC). CD is an inflammatory condition affecting any part of the digestive tract between the mouth and anus, but, most commonly, the ileum and colon. It is distinguished by the presence of granulomas in the mucosal tissue and patchy areas of transmural inflammation. UC is restricted to the colon and is manifest as continuous inflammation starting from the rectum and extending back towards the cecum. Inflammation in UC is primarily restricted to mucosal layers. Research is ongoing to understand the causality of these two diseases, and advances in understanding of their pathology have resulted from the variety of mouse models of IBD that have emerged since the early 1990s. Described in this unit are contemporary mouse models of these conditions and examples of their use in drug discovery.
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33
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Maxwell JR, Brown WA, Smith CL, Byrne FR, Viney JL. Methods of inducing inflammatory bowel disease in mice. ACTA ACUST UNITED AC 2012; Chapter 5:Unit5.58. [PMID: 22294404 DOI: 10.1002/0471141755.ph0558s47] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Animal models of experimentally induced inflammatory bowel disease (IBD) are useful for understanding more about the mechanistic basis of disease, identifying new targets for therapeutic intervention, and testing novel therapeutic agents. This unit provides detailed protocols for four of the most commonly used mouse models of experimentally induced intestinal inflammation: chemical induction of colitis by dextran sodium sulfate (DSS), hapten-induced colitis via 2,4,6-trinitrobenzene sulfonic acid (TNBS), Helicobacter-induced colitis in mdr1a(-/-) mice, and the CD4(+) CD45RB(hi) SCID transfer colitis model.
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Kanneganti M, Kamba A, Mizoguchi E. Role of chitotriosidase (chitinase 1) under normal and disease conditions. ACTA ACUST UNITED AC 2012; 5:1-9. [PMID: 23439988 DOI: 10.2174/1875044301205010001] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Mammalian chitinases belong to the glycosyl hydrolase 18 family based on structural homology and the family includes a large number of bacterial and eukaryotic chitinases. Among the mammalian chitinases, chitotriosidase (CHIT1) and acidic mammalian chitinase (AMCase) are capable of hydrolyzing the β-(1, 4)-linkage between the adjacent N-acetyl glucosamine residues of chitin. CHIT1 is one of the most abundantly secreted proteins, being mainly produced by activated macrophages and epithelial cells. CHIT1 plays a pivotal role in the context of infectious disease including malaria and fungi infections as a host defense towards chitin in pathogen's cell structure and as a diagnostic marker of disease. In contrast, CHI1 released by activated Kupffer cells in liver could induce hepatic fibrosis and cirrhosis. Increased serum levels of CHIT1 were observed in patients with many disorders, including Gaucher's disease, bronchial asthma, and atherosclerosis. Therefore, CHIT1 seems to have dual (regulatory and pathogenic) roles depending on the disease and producing cell types during the inflammatory conditions.
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Affiliation(s)
- Manasa Kanneganti
- Gastrointestinal Unit, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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35
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Whitmire JM, Merrell DS. Successful culture techniques for Helicobacter species: general culture techniques for Helicobacter pylori. Methods Mol Biol 2012; 921:17-27. [PMID: 23015487 DOI: 10.1007/978-1-62703-005-2_4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Half of the world's population is persistently infected with Helicobacter pylori. The chronicity of this infection ultimately elicits clinical manifestations ranging from gastritis and peptic ulcers to adenocarcinoma and MALT lymphoma. Laboratory research following the initial observations of Helicobacter species was greatly hindered by an inability to isolate and culture the bacteria. Thus, the ability to culture bacterial species from this genus is an extremely important step in expanding clinical knowledge and development of therapies. This chapter describes successful techniques for culturing H. pylori on selective horse blood agar media and in Brucella broth liquid media. Additionally, the specific growth requirements of other Helicobacter species are noted.
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Affiliation(s)
- Jeannette M Whitmire
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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36
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Treuting PM, Clifford CB, Sellers RS, Brayton CF. Of mice and microflora: considerations for genetically engineered mice. Vet Pathol 2011; 49:44-63. [PMID: 22173977 DOI: 10.1177/0300985811431446] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The phenotype of genetically engineered mice is a combination of both genetic and environmental factors that include the microflora of the mouse. The impact a particular microbe has on a mouse reflects the host-microbe interaction within the context of the mouse genotype and environment. Although often considered a confounding variable, many host-microbe interactions have resulted in the generation of novel model systems and characterization of new microbial agents. Microbes associated with overt disease in mice have been the historical focus of the laboratory animal medical and pathology community and literature. The advent of genetic engineering and the complex of mouse models have revealed previously unknown or disregarded agents that now oblige the attention of the biomedical research community. The purpose of this article is to describe and illustrate how phenotypes can be affected by microflora by focusing on the infectious diseases present in genetically engineered mouse (GEM) colonies of our collective institutions and by reviewing important agents that are rarely seen in most research facilities today. The goal is to introduce the concept of the role of microflora on phenotypes and in translational research using GEM models.
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Affiliation(s)
- P M Treuting
- Department of Comparative Medicine & Histology and Imaging Core, School of Medicine, University of Washington, T140 Health Science Center, Box 357190, Seattle, WA 98195-7190, USA.
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The role of P-glycoprotein and breast cancer resistance protein (BCRP) in bacterial attachment to human gastrointestinal cells. J Crohns Colitis 2011; 5:531-42. [PMID: 22115371 DOI: 10.1016/j.crohns.2011.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Revised: 04/21/2011] [Accepted: 05/06/2011] [Indexed: 02/08/2023]
Abstract
BACKGROUND AND AIMS Active efflux proteins such as P-glycoprotein (P-gp) are thought to have a protective role in the intestinal tract by preventing xenotoxin absorption. Some bacteria also need to adhere to the intestinal tract before causing disease through adhesin secretion. Thus, this study was initiated to examine whether any association exists between bacterial adhesion. METHODS Three human cell lines (Caco2, RKO, and MCF7), and 6 species of bacteria were used in this study (Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Klebsiella pneumoniae, Clostridium sporogenes and Pseudomonas aeruginosa). Following incubation of our cells with active efflux inhibitors, bacteria incubated with a stable fluorescent dye were co-incubated at 37°C for various times up to 240min. Fluorescence intensity was used to compare bacterial attachment to these cell lines with either normal efflux protein expression or with induction or inhibition of efflux proteins. RESULTS P-gp inhibition by either PSC-833 or GF120918 resulted in a significant increase of all bacterial attachment to Caco2 cells up to 3 fold. RKO cells and MCF7 cells did not alter their bacterial attachment with PSC-833. Fumitremorgen C, a dedicated BCRP inhibitor had no effect. In addition, rifampicin, a P-gp inducer, resulted in some limited reduction in Salmonella and Klebsiella attachment only. CONCLUSIONS These results indicate P-gp expression may contribute to the resistance of potential bacterial toxicity, by preventing them adhering to human enterocytes cells in the gastrointestinal tract, which may reduce the risk or intensity of gastrointestinal disorders.
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P-glycoprotein induction by breast milk attenuates intestinal inflammation in experimental necrotizing enterocolitis. J Transl Med 2011; 91:1668-79. [PMID: 21788941 PMCID: PMC3909679 DOI: 10.1038/labinvest.2011.113] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
P-glycoprotein (Pgp), a product of the multi-drug resistance gene MDR1a, is a broad specificity efflux ATP cassette transmembrane transporter that is predominantly expressed in epithelial tissues. Because mdr1a(-/-) mice tend to develop spontaneous colitis in bacteria-dependent manner, Pgp is believed to have a role in protection of the intestinal epithelium from luminal bacteria. Here we demonstrate that levels of Pgp in the small intestine of newborn rodents dramatically increase during breastfeeding, but not during formula feeding (FF). In rats and mice, levels of intestinal Pgp peak on days 3-7 and 1-5 of breastfeeding, respectively. The mdr1a(-/-) neonatal mice subjected to FF, hypoxia, and hypothermia have significantly higher incidence and pathology, as well as significantly earlier onset of necrotizing enterocolitis (NEC) than congenic wild type mice. Breast-fed mdr1a(-/-) neonatal mice are also more susceptible to intestinal damage caused by the opportunistic pathogen Cronobacter sakazakii that has been associated with hospital outbreaks of NEC. Breast milk, but not formula, induces Pgp expression in enterocyte cell lines in a dose- and time-dependent manner. High levels of ectopically expressed Pgp protect epithelial cells in vitro from apoptosis induced by C. sakazakii. Taken together, these results show that breast milk-induced expression of Pgp may have a role in the protection of the neonatal intestinal epithelium from injury associated with nascent bacterial colonization.
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39
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Helicobacter bilis colonization enhances susceptibility to Typhlocolitis following an inflammatory trigger. Dig Dis Sci 2011; 56:2838-48. [PMID: 21503679 DOI: 10.1007/s10620-011-1701-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 03/29/2011] [Indexed: 12/11/2022]
Abstract
BACKGROUND Aberrant mucosal immune responses to antigens of the resident microbiota are a significant cause of inflammatory bowel diseases (IBD), as are genetic and environmental factors. Previous work from our laboratory demonstrated that Helicobacter bilis colonization of immunocompetent, defined microbiota mice induced antigen-specific immune responses to the resident microbiota, yet these mice failed to develop colitis, suggesting that the immunological provocation induced by H. bilis alone was insufficient to induce disease. AIM The purpose of this study was to test the hypothesis that the introduction of a bacterial provocateur such as H. bilis enhances the host's susceptibility to IBD following an inflammatory event. METHODS Defined microbiota (DM) mice colonized with H. bilis were administered low dose (1.5%) dextran sodium sulfate (DSS) in drinking water for 5 days followed by a 4-day restitution period. Severity of lesions was assessed grossly and microscopically. Differential expression of select mucosal genes and histopathologic lesions was characterized. RESULTS Helicobacter bilis colonization increased the severity of intestinal inflammation induced by an inflammatory trigger in the form of low-dose DSS. An analysis of the molecular and cellular mechanisms associated with H. bilis colonization revealed significant increases in expression of mucosal genes associated with lymphocyte activation and inflammatory cell chemotaxis as well as increased infiltration of mucosal macrophages and T cells in mice colonized with H. bilis prior to DSS treatment versus DSS treatment alone. CONCLUSIONS These results indicate that prior colonization with H. bilis heightens the host's sensitivity to enteric inflammation by altering mucosal homeostasis and initiating immune cell activation and migration.
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40
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Smet A, Flahou B, Mukhopadhya I, Ducatelle R, Pasmans F, Haesebrouck F, Hold GL. The other Helicobacters. Helicobacter 2011; 16 Suppl 1:70-5. [PMID: 21896089 DOI: 10.1111/j.1523-5378.2011.00884.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The last year has seen an interesting and important collection of evidence presented in the field of the "other" than Helicobacter pylori Helicobacters. Associations with adult ulcerative colitis and biliary/hepatic disease have been described. New insights into the immune response and subsequent pathogenesis associated with infection have also been published. Genomic advances include description of new and unique species and the complete genome description for both Helicobacter felis and Helicobacter suis. Molecular studies have also elucidated the mechanism of action of some functional components of these organisms.
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Affiliation(s)
- Annemieke Smet
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
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41
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Lencioni KC, Drivdahl R, Seamons A, Treuting PM, Brabb T, Maggio-Price L. Lack of effect of murine norovirus infection on a mouse model of bacteria-induced colon cancer. Comp Med 2011; 61:219-226. [PMID: 21819691 PMCID: PMC3123754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 12/25/2010] [Accepted: 01/17/2011] [Indexed: 05/31/2023]
Abstract
Murine norovirus (MNV) is endemic in mouse research facilities in the United States and Europe, with a prevalence as high as 58% to 64%. Because of MNV's orofecal route of infection, clinically silent persistent infections in some mouse strains, and proclivity for macrophage and dendritic cells, its presence in mouse colonies has potential to alter phenotypes in experimental mouse models, particularly those involving inflammation and immunologic responses. Although MNV is subclinical, not causing overt disease in immunocompetent mice, we found that MNV infection can accelerate bacteria-induced inflammatory bowel disease (IBD) progression in Mdr1a(-/-) mice. The studies presented here examined whether MNV infection also affects the phenotype of a bacterially driven mouse model of inflammation-associated colon cancer in genetically susceptible Smad3(-/-) mice. In vitro culture of bone-marrow-derived macrophages (BMDM) was used to determine whether MNV4 influenced macrophage cytokine production. For in vivo studies, Smad3(-/-) mice were infected with MNV4 one week prior to infection with Helicobacter. Mice were monitored for 17 to 32 wk for development of IBD and colon cancer, and tissues were analyzed histopathologically. Although in vitro infection of BMDM with MNV4 led to increased inflammatory cytokine production, infection with MNV4 in vivo did not result in any statistically significant differences in survival, IBD scores, tumor incidence, or tumor phenotype in Smad3(-/-) mice. In addition, MNV infection alone did not result in IBD or colon cancer. Therefore MNV infection alone or in conjunction with Helicobacter does not alter the development or progression of IBD or colon cancer in Smad3(-/-) mice.
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Affiliation(s)
- Karen C Lencioni
- Department of Comparative Medicine, University of Washington, Seattle, Washington
- Office of Laboratory Resources, California Institute of Technology, Pasadena, California
| | - Rolf Drivdahl
- Department of Comparative Medicine, University of Washington, Seattle, Washington
| | - Audrey Seamons
- Department of Comparative Medicine, University of Washington, Seattle, Washington
| | - Piper M Treuting
- Department of Comparative Medicine, University of Washington, Seattle, Washington
| | - Thea Brabb
- Department of Comparative Medicine, University of Washington, Seattle, Washington
| | - Lillian Maggio-Price
- Department of Comparative Medicine, University of Washington, Seattle, Washington
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Fox JG, Ge Z, Whary MT, Erdman SE, Horwitz BH. Helicobacter hepaticus infection in mice: models for understanding lower bowel inflammation and cancer. Mucosal Immunol 2011; 4:22-30. [PMID: 20944559 PMCID: PMC3939708 DOI: 10.1038/mi.2010.61] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Pioneering work in the 1990s first linked a novel microaerobic bacterium, Helicobacter hepaticus, with chronic active hepatitis and inflammatory bowel disease in several murine models. Targeted H. hepaticus infection experiments subsequently demonstrated its ability to induce colitis, colorectal cancer, and extraintestinal diseases in a number of mouse strains with defects in immune function and/or regulation. H. hepaticus is now widely utilized as a model system to dissect how intestinal microbiota interact with the host to produce both inflammatory and tolerogenic responses. This model has been used to make important advances in understanding factors that regulate both acquired and innate immune response within the intestine. Further, it has been an effective tool to help define the function of regulatory T cells, including their ability to directly inhibit the innate inflammatory response to gut microbiota. The complete genomic sequence of H. hepaticus has advanced the identification of several virulence factors and aided in the elucidation of H. hepaticus pathogenesis. Delineating targets of H. hepaticus virulence factors could facilitate novel approaches to treating microbially induced lower bowel inflammatory diseases.
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Affiliation(s)
- JG Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA,Corresponding author. Mailing address: Division of Comparative Medicine, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 16-825, Cambridge, MA 02139. Phone (617) 253-1735. Fax: (617) 258-5708.
| | - Z Ge
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | - MT Whary
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | - SE Erdman
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA
| | - BH Horwitz
- Department of Pathology, Brigham and Women’s Hospital, Boston, MA
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Abstract
Recently, an unprecedented effort has been directed at understanding the interplay between chronic inflammation and development of cancer, with the case of inflammatory bowel disease (IBD)-associated colorectal cancer at the forefront of this research endeavor. The last decade has been particularly fertile, with the discovery of numerous innovative paradigms linking various inflammatory, proliferative, and innate and adaptive immune signaling pathways to the development of colorectal cancer. Because of the preponderant role of the intestinal microbiota in the initiation and progression of IBD, recent efforts have been directed at understanding the relationship between bacteria and colorectal cancer. The microbiota and its collective genome, the microbiome, form a diverse and complex ecological community that profoundly impacts intestinal homeostasis and disease states. This review will discuss the differential influence of the microbiota on the development of IBD-associated colorectal cancer and highlight the role of innate immune sensor-dependent as well as -independent mechanisms in this pathology.
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Affiliation(s)
- Janelle C Arthur
- Department of Medicine and the Center for Gastrointestinal Biology and Disease, University of North Carolina, Chapel Hill, North Carolina 27599-7080, USA
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Eaton KA, Opp JS, Gray BM, Bergin IL, Young VB. Ulcerative typhlocolitis associated with Helicobacter mastomyrinus in telomerase-deficient mice. Vet Pathol 2010; 48:713-25. [PMID: 20926734 DOI: 10.1177/0300985810383876] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Telomerase deficiency induces early senescence and defects in proliferating cell populations, but in mice it has not been associated with inflammatory bowel disease. Genetically engineered mice lacking either telomerase reverse transcriptase (TERT) or telomerase RNA were examined for chronic diarrhea and wasting. Affected mice had pasty stools, thickened nondistensible colon walls, and contracted ceca. Histologically, the cecal mucosa was largely replaced by inflammatory infiltrate consisting of plasma cells, neutrophils, lymphocytes, and macrophages with marked widespread fibrosis and ulceration. Remaining epithelium was disorganized and hyperplastic, with multifocal dysplasia. Colonic mucosa was markedly hyperplastic with similar inflammation and epithelial dysplasia. Multifocal adenomatous hyperplasia, but no inflammation, was present in the small intestine. Microaerophilic spiral bacteria with 16S rRNA gene sequences identical to Helicobacter mastomyrinus were isolated from the colon and cecum. Severe granulomatous typhlocolitis without epithelial dysplasia developed in germ-free recombination-activating gene (RAG) knockout (KO) recipients of CD4+ T cells and inoculated with cecal contents from affected TERT KO mice and in specific pathogen-free recipient RAG KO mice and interleukin-10 KO mice inoculated with H mastomyrinus. Typhlocolitis in mice given H mastomyrinus was more severe than in mice given Helicobacter hepaticus. Telomerase-deficient mice are susceptible to helicobacter-associated typhlocolitis. H mastomyrinus causes severe disease in susceptible mouse strains.
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Affiliation(s)
- K A Eaton
- University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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Abstract
Differential alteration of Toll-like receptor (TLR) expression in inflammatory bowel disease (IBD) was first described 10 years ago. Since then, studies from many groups have led to the current concept that TLRs represent key mediators of innate host defense in the intestine, involved in maintaining mucosal as well as commensal homeostasis. Recent findings in diverse murine models of colitis have helped to reveal the mechanistic importance of TLR dysfunction in IBD pathogenesis. It has become evident that environment, genetics, and host immunity form a multidimensional and highly interactive regulatory triad that controls TLR function in the intestinal mucosa. Imbalanced relationships within this triad may promote aberrant TLR signaling, critically contributing to acute and chronic intestinal inflammatory processes in IBD colitis and associated cancer.
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Affiliation(s)
- Elke Cario
- Division of Gastroenterology & Hepatology, University Hospital of Essen, and Medical School, University of Duisburg-Essen, Essen, Germany.
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The impact of the microbiota on the pathogenesis of IBD: lessons from mouse infection models. Nat Rev Microbiol 2010; 8:564-77. [PMID: 20622892 DOI: 10.1038/nrmicro2403] [Citation(s) in RCA: 269] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a major human health problem. The bacteria that live in the gut play an important part in the pathogenesis of IBD. However, owing to the complexity of the gut microbiota, our understanding of the roles of commensal and pathogenic bacteria in establishing a healthy intestinal barrier and in its disruption is evolving only slowly. In recent years, mouse models of intestinal inflammatory disorders based on defined bacterial infections have been used intensively to dissect the roles of individual bacterial species and specific bacterial components in the pathogenesis of IBD. In this Review, we focus on the impact of pathogenic and commensal bacteria on IBD-like pathogenesis in mouse infection models and summarize important recent developments.
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Kosaka T, Tajima Y, Kuroki T, Mishima T, Adachi T, Tsuneoka N, Fukuda K, Kanematsu T. Helicobacter bilis colonization of the biliary system in patients with pancreaticobiliary maljunction. Br J Surg 2010; 97:544-9. [PMID: 20155791 DOI: 10.1002/bjs.6907] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Helicobacter bilis is considered to be a causative factor in the pathogenesis of biliary cancer. This study investigated the prevalence of H. bilis colonization of the biliary system of patients with pancreaticobiliary maljunction (PBM). METHODS Bile juice and biliary tissue samples were collected from 17 patients with PBM and 27 controls who had benign biliary disease without PBM. DNA extracted from each biliary sample was subjected to polymerase chain reaction (PCR) analysis for H. bilis and Helicobacter pylori. RESULTS PCR assays revealed that 12 of the 17 patients with PBM were positive for H. bilis DNA, compared with eight of 27 patients without PBM (P = 0.009). Among patients with PBM, H. bilis DNA was identified in six of eight children, including a 2-month-old infant, and in six of nine adults. The high prevalence of H. bilis DNA in the biliary system of patients with PBM was independent of age, sex, common bile duct dilatation, configuration of the pancreatic and bile ducts, and amylase activity in bile. CONCLUSION H. bilis colonization of the biliary system is extremely common in patients with PBM. This may point to a role in the pathogenesis of biliary cancer.
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Affiliation(s)
- T Kosaka
- Department of Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan.
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Mercado-Lubo R, McCormick BA. The interaction of gut microbes with host ABC transporters. Gut Microbes 2010; 1:301-306. [PMID: 21327038 PMCID: PMC3023614 DOI: 10.4161/gmic.1.5.12925] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 06/30/2010] [Accepted: 07/08/2010] [Indexed: 02/08/2023] Open
Abstract
ATP binding cassette (ABC) transporters are increasingly recognized for their ability to modulate the absorption, distribution, metabolism, secretion and toxicity of xenobiotics. In addition to their essential function in drug resistance, there is also emerging evidence documenting the important role ABC transporters play in tissue defense. In this respect, the gastrointestinal tract represents a critical vanguard of defense against oral exposure of drugs while at the same time functions as a physical barrier between the lumenal contents (including bacteria) and the intestinal epithelium. Given emerging evidence suggesting that multidrug resistance protein (MDR) plays an important role in host-bacterial interactions in the gastrointestinal tract, this review will discuss the interplay between MDR of the intestinal epithelial cell barrier and gut microbes in health and disease. In particular, we will explore host-microbe interactions involving three apically restricted ABC transporters of the intestinal epithelium; P-glycoprotein (P-gp), multidrug resistance-associated protein 2 (MRP2) and cystic fibrosis transmembrane regulator (CFTR).
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Fox JG, Shen Z, Muthupalani S, Rogers AR, Kirchain SM, Dewhirst FE. Chronic hepatitis, hepatic dysplasia, fibrosis, and biliary hyperplasia in hamsters naturally infected with a novel Helicobacter classified in the H. bilis cluster. J Clin Microbiol 2009; 47:3673-81. [PMID: 19759229 PMCID: PMC2772605 DOI: 10.1128/jcm.00879-09] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2009] [Revised: 06/29/2009] [Accepted: 08/30/2009] [Indexed: 01/15/2023] Open
Abstract
We recently described helicobacter-associated progressive, proliferative, and dysplastic typhlocolitis in aging (18- to 24-month-old) Syrian hamsters. Other pathogens associated with typhlocolitis in hamsters, Clostridium difficile, Lawsonia intracellularis, and Giardia spp., were not indentified. The presence of Helicobacter genus-specific DNA was noted by PCR in cecal and paraffin-embedded liver samples from aged hamsters by the use of Helicobacter-specific PCR primers. By 16S rRNA analysis, the Helicobacter sp. isolated from the liver tissue was identical to the cecal isolates from hamsters. The six hamster 16S rRNA sequences form a genotypic cluster most closely related to Helicobacter sp. Flexispira taxon 8, part of the Helicobacter bilis/H. cinaedi group. Livers from aged helicobacter-infected hamsters showed various stages of predominantly portocentric and, to a lesser extent, perivenular fibrosis. Within nodules, there was cellular atypia consistent with nodular dysplasia. The livers also exhibited a range of chronic active portal/interface and lobular inflammation, with significant portal hepatitis being present. The inflammation was composed of a mixture of lymphocytes, neutrophils, and macrophages, indicative of its chronic-active nature in these aged hamsters infected with Helicobacter spp. The isolation of novel Helicobacter spp., their identification by PCR from the diseased livers of aged hamsters, and their taxonomic classification as belonging to the Helicobacter bilis cluster strengthen the argument that H. bilis and closely related Helicobacter spp. play an etiological role in hepatobiliary disease in both animals and humans.
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MESH Headings
- Animals
- Biliary Tract Diseases/microbiology
- Biliary Tract Diseases/veterinary
- Cecum/microbiology
- Cluster Analysis
- Cricetinae
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Bacterial/isolation & purification
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Fibrosis/microbiology
- Fibrosis/veterinary
- Helicobacter/classification
- Helicobacter/genetics
- Helicobacter/isolation & purification
- Helicobacter/pathogenicity
- Helicobacter Infections/microbiology
- Helicobacter Infections/pathology
- Helicobacter Infections/veterinary
- Hepatitis, Chronic/microbiology
- Hepatitis, Chronic/pathology
- Hepatitis, Chronic/veterinary
- Hyperplasia/microbiology
- Hyperplasia/veterinary
- Inflammation/pathology
- Liver/microbiology
- Liver/pathology
- Liver Cirrhosis/microbiology
- Liver Cirrhosis/pathology
- Liver Cirrhosis/veterinary
- Lymphocytes/immunology
- Macrophages/immunology
- Mesocricetus/microbiology
- Molecular Sequence Data
- Neutrophils/immunology
- Polymerase Chain Reaction
- Polymorphism, Restriction Fragment Length
- RNA, Bacterial/genetics
- RNA, Bacterial/isolation & purification
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
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Affiliation(s)
- J G Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, 77 Massachusetts Ave., Bldg. 16-825, Cambridge, MA 02139, USA.
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Abstract
Rodent health monitoring programs make an essential contribution to biomedical research by identifying the presence of infectious agents that might confound animal research. The authors discuss the types of diagnostic tests available, which agents deserve monitoring, and the appropriate frequency for such interventions.
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