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Fujimori S. Progress in elucidating the relationship between Helicobacter pylori infection and intestinal diseases. World J Gastroenterol 2021; 27:8040-8046. [PMID: 35068852 PMCID: PMC8704277 DOI: 10.3748/wjg.v27.i47.8040] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/30/2021] [Accepted: 12/08/2021] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) infection causes changes to the intestinal flora, such as small intestinal bacterial overgrowth, and increases gastric acid secretion-stimulating gastrointestinal hormones, mainly gastrin, due to a decrease in gastric acid caused by atrophic gastritis. In addition, the cellular components of H. pylori travel through the intestinal tract, so the bacterial infection affects the immune system. Therefore, the effects of H. pylori infection are observed not only in the stomach and the proximal duodenum but also in the small and large intestines. In particular, meta-analyses reported that H. pylori-infected individuals had an increased risk of colorectal adenoma and colorectal cancer. Moreover, a recent study reported that the risk of developing colorectal cancer was increased in subjects carrying H. pylori vacuolating cytotoxin A antibody. In addition, it has been reported that H. pylori infection exacerbates the symptoms of Fabry’s disease and familial Mediterranean fever attack and is involved in irritable bowel syndrome and small intestinal ulcers. On the other hand, some studies have reported that the frequency of ulcerative colitis, Crohn’s disease, and celiac disease is low in H. pylori-infected individuals. Thus, H. pylori infection is considered to have various effects on the small and large intestines. However, few studies have reported on these issues, and the details of their effects have not been well elucidated. Therefore, additional studies are needed.
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Affiliation(s)
- Shunji Fujimori
- Department of Gastroenterology, Chiba Hokusoh Hospital, Nippon Medical School, Chiba 270-1694, Japan
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Lee Y, Kamada N, Moon JJ. Oral nanomedicine for modulating immunity, intestinal barrier functions, and gut microbiome. Adv Drug Deliv Rev 2021; 179:114021. [PMID: 34710529 PMCID: PMC8665886 DOI: 10.1016/j.addr.2021.114021] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 10/17/2021] [Accepted: 10/20/2021] [Indexed: 12/12/2022]
Abstract
The gastrointestinal tract (GIT) affects not only local diseases in the GIT but also various systemic diseases. Factors that can affect the health and disease of both GIT and the human body include 1) the mucosal immune system composed of the gut-associated lymphoid tissues and the lamina propria, 2) the intestinal barrier composed of mucus and intestinal epithelium, and 3) the gut microbiota. Selective delivery of drugs, including antigens, immune-modulators, intestinal barrier enhancers, and gut-microbiome manipulators, has shown promising results for oral vaccines, immune tolerance, treatment of inflammatory bowel diseases, and other systemic diseases, including cancer. However, physicochemical and biological barriers of the GIT present significant challenges for successful translation. With the advances of novel nanomaterials, oral nanomedicine has emerged as an attractive option to not only overcome these barriers but also to selectively deliver drugs to the target sites in GIT. In this review, we discuss the GIT factors and physicochemical and biological barriers in the GIT. Furthermore, we present the recent progress of oral nanomedicine for oral vaccines, immune tolerance, and anti-inflammation therapies. We also discuss recent advances in oral nanomedicine designed to fortify the intestinal barrier functions and modulate the gut microbiota and microbial metabolites. Finally, we opine about the future directions of oral nano-immunotherapy.
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Affiliation(s)
- Yonghyun Lee
- Department of Pharmacy, College of Pharmacy, Ewha Womans University, Seoul 03760, South Korea; Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, South Korea.
| | - Nobuhiko Kamada
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan, 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA
| | - James J Moon
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI 48109 USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA; Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109 USA.
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Jing X, Min C, Qi Yun L, Shun Qin H, Li Rui L, Jia L, Run Mei M. Toll-like receptor 2/4 inhibitors can reduce preterm birth in mice. J Int Med Res 2021; 48:300060520933795. [PMID: 33100071 PMCID: PMC7604950 DOI: 10.1177/0300060520933795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Objectives Preterm birth (PTB) occurs in 5% to 18% of newborns. However, the underlying inflammatory mechanisms have not been elucidated. Methods We established a mouse model of infection-associated PTB. Physical signs in pregnant mice with or without lipopolysaccharide (LPS) treatment were observed, and the frequencies of Toll-like receptor (TLR)2- and TLR4-positive CD11b+ cells were analyzed. Cytokine levels in plasma and pathological changes were assessed following LPS treatment. A rescue experiment was used to probe potential immunologic mechanisms underlying PTB. Results Lymphocyte infiltration could be observed in the placentas of mice following intrauterine injection with LPS. The percentage of inflammatory cells decreased 12 hours after treatment. Moreover, TLR2 and TLR4 expression in peripheral blood cells was significantly increased 4 hours after intraperitoneal injection of LPS. Peak TLR2 and TLR4 expression in peripheral blood cells occurred 8 hours post-treatment. TLR4 and TLR-2/4 inhibitors reduced levels of interleukin-10, interferon-γ, and tumor necrosis factor-α in peripheral blood and delayed PTB. Conclusions TLR2 and TLR4 inhibition could play important roles in PTB.
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Affiliation(s)
- Xu Jing
- First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Chen Min
- Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Liu Qi Yun
- First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Hu Shun Qin
- First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Li Li Rui
- First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Li Jia
- First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Ma Run Mei
- First Affiliated Hospital of Kunming Medical University, Kunming, China
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Ramani S, Chauhan N, Khatri V, Vitali C, Kalyanasundaram R. Wuchereria bancrofti macrophage migration inhibitory factor-2 (rWbaMIF-2) ameliorates experimental colitis. Parasite Immunol 2020; 42:e12698. [PMID: 31976564 DOI: 10.1111/pim.12698] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 12/20/2022]
Abstract
Immunomodulatory molecules produced by helminth parasites are receiving much attention recently as novel therapeutic agents for inflammation and autoimmune diseases. In this study, we show that macrophage migration inhibitory factor (MIF) homologue from the filarial parasite, Wuchereria bancrofti (rWbaMIF-2), can suppress inflammation in a dextran sulphate sodium salt (DSS)-induced colitis model. The disease activity index (DAI) in DSS given mice showed loss of body weight and bloody diarrhoea. At autopsy, colon of these mice showed severe inflammation and reduced length. Administration of rWbaMIF-2 significantly reduced the DAI in DSS-induced colitis mice. rWbaMIF-2-treated mice had no blood in the stools, and their colon length was similar to the normal colon with minimal inflammation and histological changes. Pro-inflammatory cytokine genes (TNF-α, IL-6, IFN-γ, IL-1β, IL-17A and NOS2) were downregulated in the colon tissue and peritoneal macrophages of rWbaMIF-2-treated mice. However, there were significant increases in IL-10-producing Treg and B1 cells in the colon and peritoneal cavity of rWbaMIF-2-treated mice. These findings suggested that rWbaMIF-2 treatment significantly ameliorated the clinical symptoms, inflammation and colon pathology in DSS given mice. This immunomodulatory effect of rWbaMIF-2 appeared to be by promoting the infiltration of Treg cells into the colon.
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Affiliation(s)
- Shriram Ramani
- Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, IL, USA
| | - Nikhil Chauhan
- Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, IL, USA
| | - Vishal Khatri
- Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, IL, USA
| | - Connie Vitali
- Department of Health Sciences Education, University of Illinois College of Medicine, Rockford, IL, USA
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Ruiz J, Kanagavelu S, Flores C, Romero L, Riveron R, Shih DQ, Fukata M. Systemic Activation of TLR3-Dependent TRIF Signaling Confers Host Defense against Gram-Negative Bacteria in the Intestine. Front Cell Infect Microbiol 2016; 5:105. [PMID: 26793623 PMCID: PMC4710052 DOI: 10.3389/fcimb.2015.00105] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 12/24/2015] [Indexed: 12/11/2022] Open
Abstract
Recognition of Gram-negative bacteria by toll-like receptor (TLR)4 induces MyD88 and TRIF mediated responses. We have shown that TRIF-dependent responses play an important role in intestinal defense against Gram-negative enteropathogens. In the current study, we examined underlying mechanisms of how systemic TRIF activation enhances intestinal immune defense against Gram-negative bacteria. First we confirmed that the protective effect of poly I:C against enteric infection of mice with Yersinia enterocolitica was dependent on TLR3-mediated TRIF signaling by using TLR3-deficient mice. This protection was unique in TRIF-dependent TLR signaling because systemic stimulation of mice with agonists for TLR2 (Pam3CSK4) or TLR5 (flagellin) did not reduce mortality on Y. enterocolitica infection. Systemic administration of poly I:C mobilized CD11c+, F4/80+, and Gr−1hi cells from lamina propria and activated NK cells in the mesenteric lymph nodes (MLN) within 24 h. This innate immune cell rearrangement was type I IFN dependent and mediated through upregulation of TLR4 followed by CCR7 expression in these innate immune cells found in the intestinal mucosa. Poly I:C induced IFN-γ expression by NK cells in the MLN, which was mediated through type I IFNs and IL-12p40 from antigen presenting cells and consequent activation of STAT1 and STAT4 in NK cells. This formation of innate immunity significantly contributed to the elimination of bacteria in the MLN. Our results demonstrated an innate immune network in the intestine that can be established by systemic stimulation of TRIF, which provides a strong host defense against Gram-negative pathogens. The mechanism underlying TRIF-mediated protective immunity may be useful to develop novel therapies for enteric bacterial infection.
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Affiliation(s)
- Jose Ruiz
- Division of Gastroenterology, Department of Medicine, University of Miami Miller School of Medicine Miami, FL, USA
| | - Saravana Kanagavelu
- Division of Gastroenterology, Department of Medicine, University of Miami Miller School of MedicineMiami, FL, USA; Division of Gastroenterology, Department of Medicine, Cedars-Sinai Medical Center, F. Widjaja Foundation, Inflammatory Bowel and Immunology Research InstituteLos Angeles, CA, USA
| | - Claudia Flores
- Division of Gastroenterology, Department of Medicine, Cedars-Sinai Medical Center, F. Widjaja Foundation, Inflammatory Bowel and Immunology Research Institute Los Angeles, CA, USA
| | - Laura Romero
- Division of Gastroenterology, Department of Medicine, University of Miami Miller School of Medicine Miami, FL, USA
| | - Reldy Riveron
- Division of Gastroenterology, Department of Medicine, University of Miami Miller School of Medicine Miami, FL, USA
| | - David Q Shih
- Division of Gastroenterology, Department of Medicine, Cedars-Sinai Medical Center, F. Widjaja Foundation, Inflammatory Bowel and Immunology Research InstituteLos Angeles, CA, USA; Department of Medicine, David Geffen School of Medicine, University of CaliforniaLos Angeles, CA, USA
| | - Masayuki Fukata
- Division of Gastroenterology, Department of Medicine, University of Miami Miller School of MedicineMiami, FL, USA; Division of Gastroenterology, Department of Medicine, Cedars-Sinai Medical Center, F. Widjaja Foundation, Inflammatory Bowel and Immunology Research InstituteLos Angeles, CA, USA; Department of Medicine, David Geffen School of Medicine, University of CaliforniaLos Angeles, CA, USA; Department of Cell Biology, University of Miami Miller School of MedicineMiami, FL, USA; Department of Biomedical Science, Cedars-Sinai Medical CenterLos Angeles, CA, USA
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Immunomodulation by gut microbiota: role of Toll-like receptor expressed by T cells. J Immunol Res 2014; 2014:586939. [PMID: 25147831 PMCID: PMC4131413 DOI: 10.1155/2014/586939] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/01/2014] [Accepted: 07/02/2014] [Indexed: 02/07/2023] Open
Abstract
A close relationship exists between gut microbiota and immune responses. An imbalance of this relationship can determine local and systemic immune diseases. In fact the immune system plays an essential role in maintaining the homeostasis with the microbiota that normally resides in the gut, while, at the same time, the gut microbiota influences the immune system, modulating number and function of effector and regulatory T cells. To achieve this aim, mutual regulation between immune system and microbiota is achieved through several mechanisms, including the engagement of toll-like receptors (TLRs), pathogen-specific receptors expressed on numerous cell types. TLRs are able to recognize ligands from commensal or pathogen microbiota to maintain the tolerance or trigger the immune response. In this review, we summarize the latest evidences about the role of TLRs expressed in adaptive T cells, to understand how the immune system promotes intestinal homeostasis, fights invasion by pathogens, and is modulated by the intestinal microbiota.
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Genetic susceptibility and gastric cancer risk: the importance of meta-analyses as a statistical tool. GASTROENTEROLOGIA Y HEPATOLOGIA 2014; 37:421-6. [PMID: 24661935 DOI: 10.1016/j.gastrohep.2014.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 01/21/2014] [Accepted: 01/29/2014] [Indexed: 12/12/2022]
Abstract
Gastric cancer (GC) is a complex disease and a worldwide health burden due to its high prevalence and poor prognosis. A deeper knowledge of the factors involved in the development and progression of GC could help to identify subpopulations at risk that therefore require surveillance or early treatment strategies. Current research is based on the study of genetic variants that confer a higher risk of GC and their interactions with environmental exposure. Recently, meta-analysis has emerged as an important statistical method involving pooling of data from individual association studies to increase statistical power and obtain more conclusive results. Given the importance of chronic inflammation in the process of gastric carcinogenesis, the present article reviews the most recent meta-analyses of the contribution of cytokine gene polymorphisms to GC risk.
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Segmented filamentous bacteria are a major group in terminal ileum of piglets. Anaerobe 2013; 23:109-11. [PMID: 23891962 DOI: 10.1016/j.anaerobe.2013.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 07/15/2013] [Accepted: 07/17/2013] [Indexed: 12/21/2022]
Abstract
Metabolically active microbiota of the porcine terminal ileum mucosa was analyzed by RT-PCR of 16S rRNAs. The majority of 1951 sequences retrieved (24.8%) displayed the closest similarity to segmented filamentous bacteria (SFB). Phylogenetic analysis inferred the host-specific clusters of SFB sequences suggesting the host-specific selection of this group of bacteria.
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Wang XM, Lu Y, Wu LY, Yu SG, Zhao BX, Hu HY, Wu HG, Bao CH, Liu HR, Wang JH, Yao Y, Hua XG, Guo HY, Shen LR. Moxibustion inhibits interleukin-12 and tumor necrosis factor alpha and modulates intestinal flora in rat with ulcerative colitis. World J Gastroenterol 2012; 18:6819-6828. [PMID: 23239920 PMCID: PMC3520171 DOI: 10.3748/wjg.v18.i46.6819] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 10/23/2012] [Accepted: 11/13/2012] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effect of moxibustion on intestinal flora and release of interleukin-12 (IL-12) and tumor necrosis factor-α (TNF-α) from the colon in rat with ulcerative colitis (UC).
METHODS: A rat model of UC was established by local stimulation of the intestine with supernatant from colonic contents harvested from human UC patients. A total of 40 male Sprague-Dawley rats were randomly divided into the following groups: normal (sham), model (UC), herb-partition moxibustion (HPM-treated), and positive control sulfasalazine (SA-treated). Rats treated with HPM received HPM at acupuncture points ST25 and RN6, once a day for 15 min, for a total of 8 d. Rats in the SA group were perfused with SA twice a day for 8 d. The colonic histopathology was observed by hematoxylin-eosin. The levels of intestinal flora, including Bifidobacterium, Lactobacillus, Escherichia coli (E. coli), and Bacteroides fragilis (B. fragilis), were tested by real-time quantitative polymerase chain reaction to detect bacterial 16S rRNA/DNA in order to determine DNA copy numbers of each specific species. Immunohistochemical assays were used to observe the expression of TNF-α and IL-12 in the rat colons.
RESULTS: HPM treatment inhibited immunopathology in colonic tissues of UC rats; the general morphological score and the immunopathological score were significantly decreased in the HPM and SA groups compared with the model group [3.5 (2.0-4.0), 3.0 (1.5-3.5) vs 6.0 (5.5-7.0), P < 0.05 for the general morphological score, and 3.00 (2.00-3.50), 3.00 (2.50-3.50) vs 5.00 (4.50-5.50), P < 0.01 for the immunopathological score]. As measured by DNA copy number, we found that Bifidobacterium and Lactobacillus, which are associated with a healthy colon, were significantly higher in the HPM and SA groups than in the model group (1.395 ± 1.339, 1.461 ± 1.152 vs 0.045 ± 0.036, P < 0.01 for Bifidobacterium, and 0.395 ± 0.325, 0.851 ± 0.651 vs 0.0015 ± 0.0014, P < 0.01 for Lactobacillus). On the other hand, E. coli and B. fragilis, which are associated with an inflamed colon, were significantly lower in the HPM and SA groups than in the model group (0.244 ± 0.107, 0.628 ± 0.257 vs 1.691 ± 0.683, P < 0.01 for E. coli, and 0.351 ± 0.181, 0.416 ± 0.329 vs 1.285 ± 1.039, P < 0.01 for B. fragilis). The expression of TNF-α and IL-12 was decreased after HPM and SA treatment as compared to UC model alone (4970.81 ± 959.78, 6635.45 ± 1135.16 vs 12333.81 ± 680.79, P < 0.01 for TNF-α, and 5528.75 ± 1245.72, 7477.38 ± 1259.16 vs 12550.29 ± 1973.30, P < 0.01 for IL-12).
CONCLUSION: HPM treatment can regulate intestinal flora and inhibit the expression of TNF-α and IL-12 in the colon tissues of UC rats, indicating that HPM can improve colonic immune response.
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Mukhopadhya I, Hansen R, El-Omar EM, Hold GL. IBD-what role do Proteobacteria play? Nat Rev Gastroenterol Hepatol 2012. [PMID: 22349170 DOI: 10.1038/nrgastro] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The gastrointestinal microbiota has come to the fore in the search for the causes of IBD. This shift has largely been driven by the finding of genetic polymorphisms involved in gastrointestinal innate immunity (particularly polymorphisms in NOD2 and genes involved in autophagy) and alterations in the composition of the microbiota that might result in inflammation (so-called dysbiosis). Microbial diversity studies have continually demonstrated an expansion of the Proteobacteria phylum in patients with IBD. Individual Proteobacteria, in particular (adherent-invasive) Escherichia coli, Campylobacter concisus and enterohepatic Helicobacter, have all been associated with the pathogenesis of IBD. In this Review, we comprehensively describe the various associations of Proteobacteria and IBD. We also examine the importance of pattern recognition in the extracellular innate immune response of the host with particular reference to Proteobacteria, and postulate that Proteobacteria with adherent and invasive properties might exploit host defenses, drive proinflammatory change, alter the intestinal microbiota in favor of dysbiosis and ultimately lead to the development of IBD.
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Affiliation(s)
- Indrani Mukhopadhya
- Gastrointestinal Research Group, Division of Applied Medicine, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
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Abstract
The gastrointestinal microbiota has come to the fore in the search for the causes of IBD. This shift has largely been driven by the finding of genetic polymorphisms involved in gastrointestinal innate immunity (particularly polymorphisms in NOD2 and genes involved in autophagy) and alterations in the composition of the microbiota that might result in inflammation (so-called dysbiosis). Microbial diversity studies have continually demonstrated an expansion of the Proteobacteria phylum in patients with IBD. Individual Proteobacteria, in particular (adherent-invasive) Escherichia coli, Campylobacter concisus and enterohepatic Helicobacter, have all been associated with the pathogenesis of IBD. In this Review, we comprehensively describe the various associations of Proteobacteria and IBD. We also examine the importance of pattern recognition in the extracellular innate immune response of the host with particular reference to Proteobacteria, and postulate that Proteobacteria with adherent and invasive properties might exploit host defenses, drive proinflammatory change, alter the intestinal microbiota in favor of dysbiosis and ultimately lead to the development of IBD.
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Affiliation(s)
- Indrani Mukhopadhya
- Gastrointestinal Research Group, Division of Applied Medicine, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
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Remus DM, Kleerebezem M, Bron PA. An intimate tête-à-tête — How probiotic lactobacilli communicate with the host. Eur J Pharmacol 2011; 668 Suppl 1:S33-42. [DOI: 10.1016/j.ejphar.2011.07.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 06/29/2011] [Accepted: 07/07/2011] [Indexed: 12/28/2022]
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