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Owen JL, Mohamadzadeh M. Microbial activation of gut dendritic cells and the control of mucosal immunity. J Interferon Cytokine Res 2013; 33:619-31. [PMID: 23962004 DOI: 10.1089/jir.2013.0046] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Current data support a role for gut colonization in maintaining balanced mucosal and systemic immune responses and have suggested aberrant innate immune recognition of enteric bacteria as an initiator of the adaptive immune damage associated with inflammatory bowel disease (Crohn's disease and ulcerative colitis). In fact, data from human studies and experimental mouse models have implicated transformation of the gut microbiota from a beneficial symbiotic state to one of imbalance or "dysbiosis" in the pathogenesis of several autoinflammatory diseases, including allergic skin and respiratory disorders, rheumatoid arthritis, type I diabetes, and colorectal cancer. The host has evolved to co-exist and maintain a mutualistic relationship with the commensal microbes of the gut, and it is the function of the host innate immune system to initiate and maintain this homeostasis, while retaining the ability to respond appropriately to pathogenic organisms. In this review, we discuss the molecular and cellular interactions of the mucosal immune system that decide this delicate balance of mutualism. Furthermore, we will highlight the role of dendritic cells in preserving this precarious balance and how gene products of commensal microbes may play an integral role in re-establishing this balance once it has gone awry.
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Affiliation(s)
- Jennifer L Owen
- 1 Department of Infectious Diseases and Pathology, University of Florida , Gainesville, Florida
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102
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Owen JL, Mohamadzadeh M. Microbial activation of gut dendritic cells and the control of mucosal immunity. J Interferon Cytokine Res 2013. [PMID: 23962004 DOI: 10.1089/jir.2013.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Current data support a role for gut colonization in maintaining balanced mucosal and systemic immune responses and have suggested aberrant innate immune recognition of enteric bacteria as an initiator of the adaptive immune damage associated with inflammatory bowel disease (Crohn's disease and ulcerative colitis). In fact, data from human studies and experimental mouse models have implicated transformation of the gut microbiota from a beneficial symbiotic state to one of imbalance or "dysbiosis" in the pathogenesis of several autoinflammatory diseases, including allergic skin and respiratory disorders, rheumatoid arthritis, type I diabetes, and colorectal cancer. The host has evolved to co-exist and maintain a mutualistic relationship with the commensal microbes of the gut, and it is the function of the host innate immune system to initiate and maintain this homeostasis, while retaining the ability to respond appropriately to pathogenic organisms. In this review, we discuss the molecular and cellular interactions of the mucosal immune system that decide this delicate balance of mutualism. Furthermore, we will highlight the role of dendritic cells in preserving this precarious balance and how gene products of commensal microbes may play an integral role in re-establishing this balance once it has gone awry.
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Affiliation(s)
- Jennifer L Owen
- 1 Department of Infectious Diseases and Pathology, University of Florida , Gainesville, Florida
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103
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Dennis KL, Wang Y, Blatner NR, Wang S, Saadalla A, Trudeau E, Roers A, Weaver CT, Lee JJ, Gilbert JA, Chang EB, Khazaie K. Adenomatous polyps are driven by microbe-instigated focal inflammation and are controlled by IL-10-producing T cells. Cancer Res 2013; 73:5905-13. [PMID: 23955389 DOI: 10.1158/0008-5472.can-13-1511] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Interleukin (IL)-10 is elevated in cancer and is thought to contribute to immune tolerance and tumor growth. Defying these expectations, the adoptive transfer of IL-10-expressing T cells to mice with polyposis attenuates microbial-induced inflammation and suppresses polyposis. To gain better insights into how IL-10 impacts polyposis, we genetically ablated IL-10 in T cells in APC(Δ468) mice and compared the effects of treatment with broad-spectrum antibiotics. We found that T cells and regulatory T cells (Treg) were a major cellular source of IL-10 in both the healthy and polyp-bearing colon. Notably, T cell-specific ablation of IL-10 produced pathologies that were identical to mice with a systemic deficiency in IL-10, in both cases increasing the numbers and growth of colon polyps. Eosinophils were found to densely infiltrate colon polyps, which were enriched similarly for microbiota associated previously with colon cancer. In mice receiving broad-spectrum antibiotics, we observed reductions in microbiota, inflammation, and polyposis. Together, our findings establish that colon polyposis is driven by high densities of microbes that accumulate within polyps and trigger local inflammatory responses. Inflammation, local microbe densities, and polyp growth are suppressed by IL-10 derived specifically from T cells and Tregs.
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Affiliation(s)
- Kristen L Dennis
- Authors' Affiliations: Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine; Department of Medicine, Knapp Center for Biomedical Discovery; Department of Ecology and Evolution, University of Chicago, Chicago; Argonne National Laboratory, Argonne, Illinois; Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; Department of Biochemistry and Molecular Biology, Mayo Clinic Scottsdale, Scottsdale, Arkansas; and Institute for Immunology, Technical University Dresden, Dresden, Germany
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104
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Goh YJ, Klaenhammer TR. A functional glycogen biosynthesis pathway in Lactobacillus acidophilus: expression and analysis of the glg operon. Mol Microbiol 2013; 89:1187-200. [PMID: 23879596 PMCID: PMC4282360 DOI: 10.1111/mmi.12338] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/20/2013] [Indexed: 01/19/2023]
Abstract
Glycogen metabolism contributes to energy storage and various physiological functions in some prokaryotes, including colonization persistence. A role for glycogen metabolism is proposed on the survival and fitness of Lactobacillus acidophilus, a probiotic microbe, in the human gastrointestinal environment. L. acidophilus NCFM possesses a glycogen metabolism (glg) operon consisting of glgBCDAP-amy-pgm genes. Expression of the glg operon and glycogen accumulation were carbon source- and growth phase-dependent, and were repressed by glucose. The highest intracellular glycogen content was observed in early log-phase cells grown on trehalose, which was followed by a drastic decrease of glycogen content prior to entering stationary phase. In raffinose-grown cells, however, glycogen accumulation gradually declined following early log phase and was maintained at stable levels throughout stationary phase. Raffinose also induced an overall higher temporal glg expression throughout growth compared with trehalose. Isogenic ΔglgA (glycogen synthase) and ΔglgB (glycogen-branching enzyme) mutants are glycogen-deficient and exhibited growth defects on raffinose. The latter observation suggests a reciprocal relationship between glycogen synthesis and raffinose metabolism. Deletion of glgB or glgP (glycogen phosphorylase) resulted in defective growth and increased bile sensitivity. The data indicate that glycogen metabolism is involved in growth maintenance, bile tolerance and complex carbohydrate utilization in L. acidophilus.
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Affiliation(s)
- Yong Jun Goh
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, NC, 27695, USA
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105
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Martín R, Miquel S, Ulmer J, Kechaou N, Langella P, Bermúdez-Humarán LG. Role of commensal and probiotic bacteria in human health: a focus on inflammatory bowel disease. Microb Cell Fact 2013; 12:71. [PMID: 23876056 PMCID: PMC3726476 DOI: 10.1186/1475-2859-12-71] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 07/18/2013] [Indexed: 02/08/2023] Open
Abstract
The human gut is one of the most complex ecosystems, composed of 1013-1014 microorganisms which play an important role in human health. In addition, some food products contain live bacteria which transit through our gastrointestinal tract and could exert beneficial effects on our health (known as probiotic effect). Among the numerous proposed health benefits attributed to commensal and probiotic bacteria, their capacity to interact with the host immune system is now well demonstrated. Currently, the use of recombinant lactic acid bacteria to deliver compounds of health interest is gaining importance as an extension of the probiotic concept. This review summarizes some of the recent findings and perspectives in the study of the crosstalk of both commensal and probiotic bacteria with the human host as well as the latest studies in recombinant commensal and probiotic bacteria. Our aim is to highlight the potential roles of recombinant bacteria in this ecosystem.
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Affiliation(s)
- Rebeca Martín
- INRA, UMR1319 Micalis, Jouy-en-Josas, F-78350, France
- AgroParisTech, UMR Micalis, Jouy-en-Josas, F-78350, France
| | - Sylvie Miquel
- INRA, UMR1319 Micalis, Jouy-en-Josas, F-78350, France
- AgroParisTech, UMR Micalis, Jouy-en-Josas, F-78350, France
| | - Jonathan Ulmer
- INRA, UMR1319 Micalis, Jouy-en-Josas, F-78350, France
- AgroParisTech, UMR Micalis, Jouy-en-Josas, F-78350, France
| | - Noura Kechaou
- INRA, UMR1319 Micalis, Jouy-en-Josas, F-78350, France
- AgroParisTech, UMR Micalis, Jouy-en-Josas, F-78350, France
| | - Philippe Langella
- INRA, UMR1319 Micalis, Jouy-en-Josas, F-78350, France
- AgroParisTech, UMR Micalis, Jouy-en-Josas, F-78350, France
| | - Luis G Bermúdez-Humarán
- INRA, UMR1319 Micalis, Jouy-en-Josas, F-78350, France
- AgroParisTech, UMR Micalis, Jouy-en-Josas, F-78350, France
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106
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Bron PA, Tomita S, Mercenier A, Kleerebezem M. Cell surface-associated compounds of probiotic lactobacilli sustain the strain-specificity dogma. Curr Opin Microbiol 2013; 16:262-9. [PMID: 23810459 DOI: 10.1016/j.mib.2013.06.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 06/07/2013] [Accepted: 06/10/2013] [Indexed: 12/31/2022]
Abstract
Probiotic lactobacilli can positively impact on the health status of targeted (diseased) populations but efficacy depends strongly on the strain employed and the molecular basis for this phenomenon is poorly understood. This review discusses the current state-of-the-art in the field of molecular probiotic-host interactions, focusing on subtle strain-specific differences in the biochemical characteristics of cell surface-associated probiotic ligands and the consequences thereof for the immune responses elicited. This research is bound to enhance our understanding of strain-specificity in relation to probiotic functionality and will allow molecular science-based design of screening and characterization assays targeted to improved selection of probiotic candidate strains. Moreover, identified bioactive effector molecules could be isolated or produced for administration in a more pharmacological regime.
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Affiliation(s)
- Peter A Bron
- TI Food and Nutrition, Nieuwe Kanaal 9A, 6709PA Wageningen, The Netherlands
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107
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Wang K, Karin M. Common flora and intestine: A carcinogenic marriage. CELLULAR LOGISTICS 2013; 3:e24975. [PMID: 24516778 PMCID: PMC3906427 DOI: 10.4161/cl.24975] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/01/2013] [Accepted: 05/08/2013] [Indexed: 12/15/2022]
Abstract
Commensal microflora engages in a symbiotic relationship with their host, and plays an important role in the development of colorectal cancer (CRC). Pathogenic bacteria promote chronic intestinal inflammation and accelerate tumorigenesis. In sporadic CRC, loss of an effective epithelial barrier occurs at early stage of CRC development. As a result, non-pathogenic bacteria and/or their products infiltrate tumor stroma, drive “tumor-elicited inflammation” and promote CRC progression by activating tumor-associated myeloid and immune cells that produce IL-23 and IL-17. In this article we will summarize the recent advances in understanding the relationship between gut flora and CRC.
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Affiliation(s)
- Kepeng Wang
- Laboratory of Gene Regulation and Signal Transduction; Department of Pharmacology and Pathology; School of Medicine; University of California, San Diego; La Jolla, CA USA
| | - Michael Karin
- Laboratory of Gene Regulation and Signal Transduction; Department of Pharmacology and Pathology; School of Medicine; University of California, San Diego; La Jolla, CA USA
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108
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The impact of Lactobacillus plantarum WCFS1 teichoic acid D-alanylation on the generation of effector and regulatory T-cells in healthy mice. PLoS One 2013; 8:e63099. [PMID: 23646181 PMCID: PMC3639951 DOI: 10.1371/journal.pone.0063099] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 03/28/2013] [Indexed: 12/24/2022] Open
Abstract
To date it remains unclear how probiotics affect the immune system. Bacterial envelope components may play an essential role, as these are the first to establish bacterial-host cell interactions. Teichoic acids (TAs), and especially lipoteichoic acids, are the most pro-inflammatory components of the gram-positive bacterial envelope. This effect is dependent on D-alanyl substitution of the TA backbone and interactions with TLR2 on host cells. Although the pro-inflammatory properties of TAs have been established in vitro, it remains unclear how TAs affect immunomodulation in vivo. In this study, we investigated the role of TA D-alanylation on L. plantarum–induced intestinal and systemic immunomodulation in vivo. For this, we compared the effect of L. plantarum WCFS1 and its TA D-Alanylation negative derivative (dltX-D) on the distribution of dendritic cell and T cell populations and responses in healthy mice. We demonstrated that the majority of the L. plantarum-induced in vivo immunomodulatory effects were dependent on D-alanylation (D-Ala), as some L. plantarum WCFS1-induced immune changes were not observed in the dltX-D-treated group and some were only observed after treatment with dltX-D. Strikingly, not only pro-inflammatory immune responses were abolished in the absence of D-Ala substitution, but also anti-inflammatory responses, such as the L. plantarum-induced generation of regulatory T cells in the spleen. With this study we provide insight in host-microbe interactions, by demonstrating the involvement of D-alanylation of TAs on the bacterial membrane in intestinal and systemic immunomodulation in healthy mice.
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109
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Selle K, Klaenhammer TR. Genomic and phenotypic evidence for probiotic influences of Lactobacillus gasseri on human health. FEMS Microbiol Rev 2013; 37:915-35. [PMID: 23488471 DOI: 10.1111/1574-6976.12021] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 02/08/2013] [Accepted: 02/15/2013] [Indexed: 12/21/2022] Open
Abstract
Certain lactic acid bacteria (LAB) have the capacity to occupy mucosal niches of humans, including the oral cavity, gastrointestinal tract, and vagina. Among commensal, LAB are species of the acidophilus complex, which have proven to be a substantial reservoir for microorganisms with probiotic attributes. Specifically, Lactobacillus gasseri is an autochthonous microorganism which has been evaluated for probiotic activity based on the availability of genome sequence and species-specific adaptation to the human mucosa. Niche-related characteristics of L. gasseri contributing to indigenous colonization include tolerance of low pH environments, resistance to bile salts, and adhesion to the host epithelium. In humans, L. gasseri elicits various health benefits through its antimicrobial activity, bacteriocin production, and immunomodulation of the innate and adaptive systems. The genomic and empirical evidence supporting use of L. gasseri in probiotic applications is substantiated by clinical trial data displaying maintenance of vaginal homeostasis, mitigation of Helicobacter pylori infection, and amelioration of diarrhea.
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Affiliation(s)
- Kurt Selle
- Department of Food, Bioprocessing & Nutrition Sciences, North Carolina State University, Raleigh, NC, USA
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110
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Musch MW, Wang Y, Claud EC, Chang EB. Lubiprostone decreases mouse colonic inner mucus layer thickness and alters intestinal microbiota. Dig Dis Sci 2013; 58:668-77. [PMID: 23329012 PMCID: PMC3618493 DOI: 10.1007/s10620-012-2509-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 12/01/2012] [Indexed: 01/02/2023]
Abstract
BACKGROUND Lubiprostone has been used to treat constipation through its effects to stimulate Cl(-) secretion, resulting in water and electrolyte secretion. AIM Potential associated changes in intestinal mucus and the colonizing bacteria (microbiome) have not been studied. As mucus obstructions may play a role in cystic fibrosis, the hypothesis that lubiprostone alters intestinal mucus and the microbiome was investigated. METHODS Ion transport studies were performed ex vivo. For mucus and microbiome studies, mice were gavaged daily with lubiprostone or vehicle. Mucin from intestinal sections was analyzed in Carnoy's fixed tissues stained with Alcian blue. Microbiome composition was analyzed by 16S rRNA gene-based sequencing. RESULTS Lubiprostone stimulated short circuit current in all mouse intestinal segments after both serosal and mucosal additions, albeit at lower concentrations in the latter. Current was Cl-dependent and blocked by mucosal diphenylcarboxylic acid, serosal bumetanide, and serosal Ba(++). The CFTR inhibitor CFTRinh172 had a marginal effect. Mucus near epithelial cells (inner layer mucus) was not present in the small intestine of any mice. Proximal colon inner mucus layer was thicker in ∆F/∆F compared with +/∆F and +/+ mice. Lubiprostone decreased inner mucus layer thickness in both proximal and distal colon of all mice. Furthermore, lubiprostone altered the intestinal microbiome by increasing abundance of Lactobacillus and Alistipes. CONCLUSIONS Lubiprostone activates non-CFTR Cl(-) secretion and alters the colonic inner mucus layer, which is associated with changes in the composition of the enteric microbiome.
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Affiliation(s)
- Mark W Musch
- Division of Biological Sciences, Department of Medicine, The University of Chicago, 900 E. 57th St., Chicago, IL 60637, USA
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111
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The quest for probiotic effector molecules—Unraveling strain specificity at the molecular level. Pharmacol Res 2013; 69:61-74. [DOI: 10.1016/j.phrs.2012.09.010] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 09/26/2012] [Accepted: 09/27/2012] [Indexed: 12/25/2022]
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112
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Bienenstock J, Gibson G, Klaenhammer TR, Walker WA, Neish AS. New insights into probiotic mechanisms: a harvest from functional and metagenomic studies. Gut Microbes 2013; 4:94-100. [PMID: 23249742 PMCID: PMC3595083 DOI: 10.4161/gmic.23283] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
There has been continued and expanding recognition of probiotic approaches for treating gastrointestinal and systemic disease, as well as increased acceptance of probiotic therapies by both the public and the medical community. A parallel development has been the increasing recognition of the diverse roles that the normal gut microbiota plays in the normal biology of the host. This advance has in turn has been fed by implementation of novel investigative technologies and conceptual paradigms focused on understanding the fundamental role of the microbiota and indeed all commensal bacteria, on known and previously unsuspected aspects of host physiology in health and disease. This review discusses current advances in the study of the host-microbiota interaction, especially as it relates to potential mechanisms of probiotics. It is hoped these new approaches will allow more rational selection and validation of probiotic usage in a variety of clinical conditions.
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Affiliation(s)
- John Bienenstock
- Pathology and Molecular Medicine; McMaster University; Hamilton, ON Canada
| | - Glenn Gibson
- School of Food Biosciences; The University of Reading; Reading, UK
| | - Todd R. Klaenhammer
- Department of Food, Bioprocessing and Nutrition Sciences; North Carolina State University; Raleigh, NC USA
| | - W. Allan Walker
- Department of Pediatrics; Mucosal Immunology Laboratory; Massachusetts General Hospital; Harvard Medical School; Boston, MA USA
| | - Andrew S. Neish
- Department of Pathology; Emory University School of Medicine; Atlanta, GA USA,Correspondence to: Andrew S. Neish,
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113
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van Baarlen P, Wells JM, Kleerebezem M. Regulation of intestinal homeostasis and immunity with probiotic lactobacilli. Trends Immunol 2013; 34:208-15. [PMID: 23485516 DOI: 10.1016/j.it.2013.01.005] [Citation(s) in RCA: 245] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 01/18/2013] [Accepted: 01/22/2013] [Indexed: 02/07/2023]
Abstract
The gut microbiota provide important stimuli to the human innate and adaptive immune system and co-mediate metabolic and immune homeostasis. Probiotic bacteria can be regarded as part of the natural human microbiota, and have been associated with improving homeostasis, albeit with different levels of success. Composition of microbiota, probiotic strain identity, and host genetic differences may account for differential modulation of immune responses by probiotics. Here, we review the mechanisms of immunomodulating capacities of specific probiotic strains, the responses they can induce in the host, and how microbiota and genetic differences between individuals may co-influence host responses and immune homeostasis.
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Affiliation(s)
- Peter van Baarlen
- Host Microbe Interactomics Group, Wageningen University, De Elst 1, 6708WD Wageningen, The Netherlands
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114
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Lightfoot YL, Mohamadzadeh M. Tailoring gut immune responses with lipoteichoic acid-deficient Lactobacillus acidophilus. Front Immunol 2013; 4:25. [PMID: 23390423 PMCID: PMC3565175 DOI: 10.3389/fimmu.2013.00025] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 01/21/2013] [Indexed: 01/11/2023] Open
Abstract
As highlighted by the development of intestinal autoinflammatory disorders when tolerance is lost, homeostatic interactions between gut microbiota, resident immune cells, and the gut epithelium are key in the maintenance of gastrointestinal health. Gut immune responses, whether stimulatory or regulatory, are dictated by the activated dendritic cells (DCs) that first interact with microorganisms and their gene products to then elicit T and B cell responses. Previously, we have demonstrated that treatment with genetically modified Lactobacillus acidophilus is sufficient to tilt the immune balance from proinflammatory to regulatory in experimental models of colitis and colon cancer. Given the significant role of DCs in efficiently orchestrating intestinal immune responses, characterization of the signals induced within these cells by the surface layer molecules, such as lipoteichoic acid (LTA), and proteins of L. acidophilus is critical for future treatment and prevention of gastrointestinal diseases. Here, we discuss the potential regulatory pathways involved in the downregulation of pathogenic inflammation in the gut, and explore questions regarding the immune responses to LTA-deficient L. acidophilus that require future studies.
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Affiliation(s)
- Yaíma L Lightfoot
- Department of Infectious Diseases and Pathology, College of Veterinary Medicine, University of Florida Gainesville, FL, USA ; Division of Gastroenterology Hepatology & Nutrition, Department of Medicine, College of Medicine, University of Florida Gainesville, FL, USA
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115
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Zeineldin M, Neufeld KL. More than two decades of Apc modeling in rodents. Biochim Biophys Acta Rev Cancer 2013; 1836:80-9. [PMID: 23333833 DOI: 10.1016/j.bbcan.2013.01.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 12/31/2012] [Accepted: 01/03/2013] [Indexed: 02/07/2023]
Abstract
Mutation of tumor suppressor gene adenomatous polyposis coli (APC) is an initiating step in most colon cancers. This review summarizes Apc models in mice and rats, with particular concentration on those most recently developed, phenotypic variation among different models, and genotype/phenotype correlations.
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Affiliation(s)
- Maged Zeineldin
- Department of Molecular Biosciences, University of Kansas, 1200 Sunnyside Ave., Lawrence, KS 66045, USA
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116
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Lightfoot YL, Yang T, Sahay B, Mohamadzadeh M. Targeting aberrant colon cancer-specific DNA methylation with lipoteichoic acid-deficient Lactobacillus acidophilus. Gut Microbes 2013; 4:84-8. [PMID: 23137966 PMCID: PMC3555892 DOI: 10.4161/gmic.22822] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pathogenic autoinflammatory responses triggered by dysregulated microbial interactions may lead to intestinal disorders and malignancies. Previously, we demonstrated that a lipoteichoic acid (LTA)-deficient Lactobacillus acidophilus strain, NCK2025, ameliorated inflammation-induced colitis, significantly reduced the number of polyps in a colonic polyposis cancer model and restored physiological homeostasis in both cases. Nonetheless, the regulatory signals delivered by NCK2025 to reprogram the gastrointestinal microenvironment, and thus resist colonic cancer progression, remain unknown. Accumulating evidence suggest that epigenetic changes, in the presence and absence of pathogenic inflammation, can result in colorectal cancer (CRC). To test possible epigenetic modifications induced by NCK2025, the expression of epigenetically regulated, CRC-associated genes was measured with and without bacterial treatment. In vivo and in vitro, NCK2025 enhanced the expression of tumor suppressor genes that may regulate CRC development. Therefore, differential epigenetic regulation of CRC-related genes by NCK2025 represents a potential therapy against colitis-associated and sporadic CRC.
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117
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Abstract
Probiotics and prebiotics are increasingly being added to foodstuffs with claims of health benefits. Probiotics are live microorganisms that are thought to have beneficial effects on the host, whereas prebiotics are ingredients that stimulate the growth and/or function of beneficial intestinal microorganisms. But can these products directly modulate immune function and influence inflammatory diseases? Here, Nature Reviews Immunology asks four experts to discuss these issues and provide their thoughts on the future application of probiotics as a disease therapy.
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118
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Lightfoot YL, Rehman HU, Myers AD, Mohamadzadeh M. Mitigating colon cancer with a novel strain of Lactobacillus acidophilus: a (re-)balancing act. Immunotherapy 2012. [PMID: 23194356 DOI: 10.2217/imt.12.98] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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