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CpG Oligodeoxynucleotides Facilitate Delivery of Whole Inactivated H9N2 Influenza Virus via Transepithelial Dendrites of Dendritic Cells in Nasal Mucosa. J Virol 2015; 89:5904-18. [PMID: 25810544 DOI: 10.1128/jvi.00296-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 03/11/2015] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED The spread of the low-pathogenicity avian H9N2 influenza virus has seriously increased the risk of a new influenza pandemic. Although whole inactivated virus (WIV) vaccine via intranasal pathway is the effective method of blocking virus transmission, the mucosal barrier seems to be a major factor hampering its development. CpG oligodeoxynucleotides, a known adjuvant, can target downstream dendritic cells (DCs) and effectively enhance the mucosal and systemic immune responses. However, the ability of CpGs to assist H9N2 WIV in transepithelial transport remains unknown. Here, in vitro and in vivo, we showed that CpGs provided assistance for H9N2 WIV in recruiting DCs to the nasal epithelial cells (ECs) and forming transepithelial dendrites (TEDs) to capture luminal viruses. CD103(+) DCs participated in this process. Chemokine CCL20 from nasal ECs played a key role in driving DC recruitment and TED formation. Virus-loaded DCs quickly migrated into the draining cervical lymph nodes (CLNs) for antigen presentation. In addition, the competence of CpGs was independent of direct epithelial transport via the transcellular or paracellular pathway. Taken together, our data demonstrated that CpGs enhanced the transport of H9N2 WIV via TEDs of nasal DCs, which might be a novel mechanism for optimal adaptive immune responses. IMPORTANCE This paper demonstrates by both an in vivo and an in vitro coculture model that CpG oligodeoxynucleotides, known as an adjuvant generally targeting downstream immune responses, also are crucial for the transport of H9N2 WIV across nasal epithelial cells (ECs) via the uptake of transepithelial dendrites (TEDs). Our results prove for the first time to our knowledge that the immune-potentiating mechanism of CpGs is based on strengthening the transepithelial uptake of H9N2 WIV in nasal mucosa. These findings provide a fresh perspective for further improvement of intranasal influenza vaccines, which are urgently needed in the face of the potential threat of H9N2 influenza.
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202
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Kolesnikov M, Farache J, Shakhar G. Intravital two-photon imaging of the gastrointestinal tract. J Immunol Methods 2015; 421:73-80. [PMID: 25801674 DOI: 10.1016/j.jim.2015.03.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 03/12/2015] [Accepted: 03/12/2015] [Indexed: 11/19/2022]
Abstract
Live imaging of the gastrointestinal tract with two-photon microscopy (TPM) has proven to be a useful tool for mucosal immunologists. It provides deep penetration of live tissues with reduced phototoxicity and photobleaching and thus excels in deciphering dynamic immunological processes that require cell motility and last minutes through hours. The few studies that employed this technique in the gut have uncovered new aspects of mucosal immunity. They focused mainly on adaptive immunity in the small intestine and exposed the details of important interactions among several epithelial and hematopoietic cell types. TPM can be employed either on explanted tissue or intravitally, as has been practiced in our lab. Intravital TPM preserves physiological conditions more faithfully, but it is a demanding technique that requires dedicated personnel. To achieve success, the peristaltic motility of the intestine must be curbed, surgical and photonic damage must be minimized, and tissue degradation must be delayed and controlled for. Here we briefly review published studies that employed intravital TPM in the gut, describe our own technique for imaging the intestinal Peyer's patches (PPs) and villi, and present some observations we made using this technique.
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Affiliation(s)
- Masha Kolesnikov
- Department of Immunology, The Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Julia Farache
- Department of Microbiology and Immunology, Harvard Medical School, Boston, MA 02115, USA
| | - Guy Shakhar
- Department of Immunology, The Weizmann Institute of Science, Rehovot, 76100, Israel.
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203
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Bose O, Baluk P, Looney MR, Cheng LE, McDonald DM, Caughey GH, Krummel MF. Mast cells present protrusions into blood vessels upon tracheal allergen challenge in mice. PLoS One 2015; 10:e0118513. [PMID: 25789765 PMCID: PMC4366375 DOI: 10.1371/journal.pone.0118513] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/11/2015] [Indexed: 11/18/2022] Open
Abstract
Mast cells (MC) and myeloid dendritic cells (DC) act proximally in detecting and processing antigens and immune insults. We sought to understand their comparative dynamic behavior with respect to the airway epithelium in the steady state and in response to an allergic stimulus in mouse trachea. We devised methods to label MC in living trachea and to demonstrate that MC and DC occupy distinct layers of the tracheal mucosa, with DC being closer to the lumen. DC numbers doubled after allergen challenge, but MC numbers remained stable. MC and DC migrated minimally in either steady state or allergen-challenge conditions, and their interactions with one another appeared to be stochastic and relatively infrequent. While DC, unlike MC, exhibited probing behaviors involving dendrites, these projections did not cross the epithelium into the airway lumen. MC typically were located too far from the epithelial surface to contact the tracheal lumen. However, MC had protrusions toward and into blood vessels, likely to load with IgE. Thus, DC and MC occupy distinct niches and engage in sessile surveillance in the mouse trachea. Little or no access of these cell types to the airway lumen suggests that trans-epithelial transport of proteins in the steady state would be required for them to access luminal antigens.
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Affiliation(s)
- Oishee Bose
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Peter Baluk
- Department of Anatomy, University of California San Francisco, San Francisco, California, United States of America
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, California, United States of America
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, and Veterans Affairs Medical Center, San Francisco, California, United States of America
| | - Mark R. Looney
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Laurence E. Cheng
- Department of Pediatrics, University of California San Francisco, San Francisco, California, United States of America
| | - Donald M. McDonald
- Department of Anatomy, University of California San Francisco, San Francisco, California, United States of America
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, California, United States of America
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, and Veterans Affairs Medical Center, San Francisco, California, United States of America
| | - George H. Caughey
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, California, United States of America
- * E-mail: (MFK); (GHC)
| | - Matthew F. Krummel
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, and Veterans Affairs Medical Center, San Francisco, California, United States of America
- * E-mail: (MFK); (GHC)
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204
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Lawler C, Milho R, May JS, Stevenson PG. Rhadinovirus host entry by co-operative infection. PLoS Pathog 2015; 11:e1004761. [PMID: 25790477 PMCID: PMC4366105 DOI: 10.1371/journal.ppat.1004761] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 02/23/2015] [Indexed: 12/27/2022] Open
Abstract
Rhadinoviruses establish chronic infections of clinical and economic importance. Several show respiratory transmission and cause lung pathologies. We used Murid Herpesvirus-4 (MuHV-4) to understand how rhadinovirus lung infection might work. A primary epithelial or B cell infection often is assumed. MuHV-4 targeted instead alveolar macrophages, and their depletion reduced markedly host entry. While host entry was efficient, alveolar macrophages lacked heparan - an important rhadinovirus binding target - and were infected poorly ex vivo. In situ analysis revealed that virions bound initially not to macrophages but to heparan+ type 1 alveolar epithelial cells (AECs). Although epithelial cell lines endocytose MuHV-4 readily in vitro, AECs did not. Rather bound virions were acquired by macrophages; epithelial infection occurred only later. Thus, host entry was co-operative - virion binding to epithelial cells licensed macrophage infection, and this in turn licensed AEC infection. An antibody block of epithelial cell binding failed to block host entry: opsonization provided merely another route to macrophages. By contrast an antibody block of membrane fusion was effective. Therefore co-operative infection extended viral tropism beyond the normal paradigm of a target cell infected readily in vitro; and macrophage involvement in host entry required neutralization to act down-stream of cell binding. All viral infections start with host entry. Entry into cells is studied widely in isolated cultures; entry into live hosts is more complicated and less well understood: our tissues have specific anatomical structures and our cells differ markedly from most cultured cells in size, shape and behaviour. The respiratory tract is a common site of virus infection. Size dictates where inhaled particles come to rest, and virus-sized particles can reach the lungs. Rhadinoviruses chronically infect both humans and economically important animals, and cause lung disease. We used a well-characterized murine example to determine how a rhadinovirus enters the lungs. At its peak, infection was prominent in epithelial cells lining the lung air spaces. However it started in macrophages, which normally clear the lungs of inhaled debris. Only epithelial cells expressed the molecules required for virus binding, but only macrophages internalized virus particles after binding; infection involved interaction between these different cell types. Blocking epithelial infection with an antibody did not stop host entry because attached antibodies increase virus uptake by lung macrophages; but an antibody that blocks macrophage infection was effective. Thus, understanding how rhadinovirus infections work in normal tissues provided important information for their control.
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Affiliation(s)
- Clara Lawler
- Sir Albert Sakzewski Virus Research Centre, School of Chemistry and Molecular Biosciences, Royal Children’s Hospital and University of Queensland, Brisbane, Australia
| | - Ricardo Milho
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Janet S. May
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Philip G. Stevenson
- Sir Albert Sakzewski Virus Research Centre, School of Chemistry and Molecular Biosciences, Royal Children’s Hospital and University of Queensland, Brisbane, Australia
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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205
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Bates JM, Flanagan K, Mo L, Ota N, Ding J, Ho S, Liu S, Roose-Girma M, Warming S, Diehl L. Dendritic cell CD83 homotypic interactions regulate inflammation and promote mucosal homeostasis. Mucosal Immunol 2015; 8:414-28. [PMID: 25204675 PMCID: PMC4326976 DOI: 10.1038/mi.2014.79] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 07/26/2014] [Indexed: 02/04/2023]
Abstract
Dendritic cells (DCs) form an extensive network in the intestinal lamina propria, which orchestrates the mucosal immune response. Alterations in DC function can predispose to inflammatory bowel disease, although by unknown mechanisms. We show that CD83, a highly regulated DC cell surface protein, modulates the immune response to prevent colitis. Mice with a conditional knockout of CD83 in DCs develop exacerbated colitis following dextran sodium sulfate challenge, whereas mucosal overexpression of CD83 inhibits DC inflammatory response and protects against colitis. These CD83 perturbations can be modeled in vitro where we show that CD83 homotypic interaction occurs via cell-cell contact and inhibits pro-inflammatory responses. CD83 knockdown or cytoplasmic truncation abrogates the effects of homotypic binding. We demonstrate that CD83 homotypic interaction regulates DC activation via the mitogen-activated protein kinase pathway by inhibiting p38α phosphorylation. Our findings indicate that CD83 homotypic interactions regulate DC activation and promote mucosal homeostasis.
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Affiliation(s)
- J M Bates
- Department of Pathology, Genetech, South San Francisco, California, USA
| | - K Flanagan
- Department of Pathology, Genetech, South San Francisco, California, USA
| | - L Mo
- Department of Pathology, Genetech, South San Francisco, California, USA
| | - N Ota
- Department of Immunology, Genetech, South San Francisco, California, USA
| | - J Ding
- Department of Immunology, Genetech, South San Francisco, California, USA
| | - S Ho
- Department of Pathology, Genetech, South San Francisco, California, USA
| | - S Liu
- Department of Pathology, Genetech, South San Francisco, California, USA
| | - M Roose-Girma
- Department of Molecular Biology, Genentech, South San Francisco, California, USA
| | - S Warming
- Department of Molecular Biology, Genentech, South San Francisco, California, USA
| | - L Diehl
- Department of Pathology, Genetech, South San Francisco, California, USA
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206
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Abstract
Intestinal epithelial cells are fundamental to maintain barrier integrity and to participate in food degradation and absorption, but they can also decipher signals coming from the outside world and 'educate' the immune system accordingly. In particular, they interact with dendritic cells (DCs) and other intraepithelial immune cells to drive tolerogenic responses under steady state, but they can also release immune mediators to recruit inflammatory cells and to elicit immunity to infectious agents. When these interactions are deregulated, immune disorders can develop. In this review, we discuss some important features of epithelial cells and DCs and their fruitful interactions.
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Affiliation(s)
- Maria Rescigno
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
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207
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Gutzeit C, Magri G, Cerutti A. Intestinal IgA production and its role in host-microbe interaction. Immunol Rev 2015; 260:76-85. [PMID: 24942683 DOI: 10.1111/imr.12189] [Citation(s) in RCA: 215] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Complex and diverse communities of bacteria establish mutualistic and symbiotic relationships with the gut after birth. The intestinal immune system responds to bacterial colonization by acquiring a state of hypo-responsiveness against commensals and active readiness against pathogens. The resulting homeostatic balance involves a continuous dialog between the microbiota and lymphocytes with the intermediation of epithelial and dendritic cells. This dialog causes massive production of immunoglobulin A (IgA), a non-inflammatory antibody specialized in mucosal protection. Here, we discuss recent advances on the regulation of intestinal IgA responses and their role in host-microbe interaction.
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Affiliation(s)
- Cindy Gutzeit
- Immunology Institute, Department of Medicine, Division of Clinical Immunology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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208
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Fulde M, Hornef MW. Maturation of the enteric mucosal innate immune system during the postnatal period. Immunol Rev 2015; 260:21-34. [PMID: 24942679 DOI: 10.1111/imr.12190] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The innate immune system instructs the host on microbial exposure and infection. This information is critical to mount a protective innate and adaptive host response to microbial challenge, but is also involved in homeostatic and adaptive processes that adjust the organism to meet environmental requirements. This is of particular importance for the neonatal host during the transition from the protected fetal life to the intense and dynamic postnatal interaction with commensal and pathogenic microorganisms. Here, we discuss both adaptive and developmental mechanisms of the mucosal innate immune system that prevent inappropriate stimulation and facilitate establishment of a stable homeostatic host-microbial interaction after birth.
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Affiliation(s)
- Marcus Fulde
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
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209
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Abstract
The intestine contains the largest pool of macrophages in the body which are essential for maintaining mucosal homeostasis in the face of the microbiota and the constant need for epithelial renewal but are also important components of protective immunity and are involved in the pathology of inflammatory bowel disease (IBD). However, defining the biological roles of intestinal macrophages has been impeded by problems in defining the phenotype and origins of different populations of myeloid cells in the mucosa. Here, we discuss how multiple parameters can be used in combination to discriminate between functionally distinct myeloid cells and discuss the roles of macrophages during homeostasis and how these may change when inflammation ensues. We also discuss the evidence that intestinal macrophages do not fit the current paradigm that tissue-resident macrophages are derived from embryonic precursors that self-renew in situ, but require constant replenishment by blood monocytes. We describe our recent work demonstrating that classical monocytes constantly enter the intestinal mucosa and how the environment dictates their subsequent fate. We believe that understanding the factors that drive intestinal macrophage development in the steady state and how these may change in response to pathogens or inflammation could provide important insights into the treatment of IBD.
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Affiliation(s)
- Calum C Bain
- Centre for Immunobiology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
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210
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Abstract
The intestine contains the largest pool of macrophages in the body which are essential for maintaining mucosal homeostasis in the face of the microbiota and the constant need for epithelial renewal but are also important components of protective immunity and are involved in the pathology of inflammatory bowel disease (IBD). However, defining the biological roles of intestinal macrophages has been impeded by problems in defining the phenotype and origins of different populations of myeloid cells in the mucosa. Here, we discuss how multiple parameters can be used in combination to discriminate between functionally distinct myeloid cells and discuss the roles of macrophages during homeostasis and how these may change when inflammation ensues. We also discuss the evidence that intestinal macrophages do not fit the current paradigm that tissue-resident macrophages are derived from embryonic precursors that self-renew in situ, but require constant replenishment by blood monocytes. We describe our recent work demonstrating that classical monocytes constantly enter the intestinal mucosa and how the environment dictates their subsequent fate. We believe that understanding the factors that drive intestinal macrophage development in the steady state and how these may change in response to pathogens or inflammation could provide important insights into the treatment of IBD.
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Affiliation(s)
- Calum C Bain
- Centre for Immunobiology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
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211
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Whole inactivated avian Influenza H9N2 viruses induce nasal submucosal dendritic cells to sample luminal viruses via transepithelial dendrites and trigger subsequent DC maturation. Vaccine 2015; 33:1382-92. [PMID: 25613720 DOI: 10.1016/j.vaccine.2015.01.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 12/23/2014] [Accepted: 01/08/2015] [Indexed: 12/13/2022]
Abstract
Nasal mucosal barrier is a key impediment for the absorption of influenza whole inactivated virus (WIV) intranasal vaccine. Yet it is still unclear how WIV cross the epithelial cells (ECs) in nasal cavity. Here, in vitro, a coculture system was well established, consisting of surrogate nasal ECs (Calu-3) and dendritic cells (DCs). After adding H9N2 WIV on the apical side of ECs, we found that submucosal DCs extended their transepithelial dendrites (TEDs) and sampled luminal viruses. However, ECs were not involved in the transepithelial transport of viruses. Subsequently, the phenotypic and functional maturation of DCs were also enhanced, whereas they were attenuated after blocking of TED formation by anti-JAM1 antibody. In vivo, we confirmed that H9N2 WIV were capable of inducing nasal submucosal DCs to sample luminal viruses via TEDs in the nasal passage but not nasal-associated lymphoid tissue (NALT). CD103(+) and CD103(-) DC subsets participated in this process. Of note, chemokine CCL20, released from the H9N2 WIV-induced ECs, played a vital role in DC recruitment and TED formation. Taken together, our findings indicated that TEDs played a critical role in facilitating viral transport across the epithelial barrier, which may guide the design of novel nasal mucosal vaccine strategies.
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212
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Caballero S, Pamer EG. Microbiota-mediated inflammation and antimicrobial defense in the intestine. Annu Rev Immunol 2015; 33:227-56. [PMID: 25581310 DOI: 10.1146/annurev-immunol-032713-120238] [Citation(s) in RCA: 186] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The diverse microbial populations constituting the intestinal microbiota promote immune development and differentiation, but because of their complex metabolic requirements and the consequent difficulty culturing them, they remained, until recently, largely uncharacterized and mysterious. In the last decade, deep nucleic acid sequencing platforms, new computational and bioinformatics tools, and full-genome characterization of several hundred commensal bacterial species facilitated studies of the microbiota and revealed that differences in microbiota composition can be associated with inflammatory, metabolic, and infectious diseases, that each human is colonized by a distinct bacterial flora, and that the microbiota can be manipulated to reduce and even cure some diseases. Different bacterial species induce distinct immune cell populations that can play pro- and anti-inflammatory roles, and thus the composition of the microbiota determines, in part, the level of resistance to infection and susceptibility to inflammatory diseases. This review summarizes recent work characterizing commensal microbes that contribute to the antimicrobial defense/inflammation axis.
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Affiliation(s)
- Silvia Caballero
- Immunology Program, Sloan Kettering Institute, Infectious Diseases Service, Memorial Sloan Kettering Cancer Center, New York, NY 10065;
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213
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214
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Abstract
Neonates face unique challenges in the period following birth. The postnatal immune system is in the early stages of development and has a range of functional capabilities that are distinct from the mature adult immune system. Bidirectional immune-microbial interactions regulate the development of mucosal immunity and alter the composition of the microbiota, which contributes to overall host well-being. In the past few years, nutrition has been highlighted as a third element in this interaction that governs host health by modulating microbial composition and the function of the immune system. Dietary changes and imbalances can disturb the immune-microbiota homeostasis, which might alter susceptibility to several autoimmune and metabolic diseases. Major changes in cultural traditions, socioeconomic status and agriculture are affecting the nutritional status of humans worldwide, which is altering core intestinal microbial communities. This phenomenon is especially relevant to the neonatal and paediatric populations, in which the microbiota and immune system are extremely sensitive to dietary influences. In this Review, we discuss the current state of knowledge regarding early-life nutrition, its effects on the microbiota and the consequences of diet-induced perturbation of the structure of the microbial community on mucosal immunity and disease susceptibility.
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215
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Brandl K, Schnabl B. Is intestinal inflammation linking dysbiosis to gut barrier dysfunction during liver disease? Expert Rev Gastroenterol Hepatol 2015; 9:1069-76. [PMID: 26088524 PMCID: PMC4828034 DOI: 10.1586/17474124.2015.1057122] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Changes in the intestinal microbiota composition contribute to the pathogenesis of many disorders including gastrointestinal and liver diseases. Recent studies have broadened our understanding of the "gut-liver" axis. Dietary changes, other environmental and genetic factors can lead to alterations in the microbiota. Dysbiosis can further disrupt the integrity of the intestinal barrier leading to pathological bacterial translocation and the initiation of an inflammatory response in the liver. In this article, the authors dissect the different steps involved in disease pathogenesis to further refine approaches for the medical management of liver diseases. The authors will specifically discuss the role of dysbiosis in inducing intestinal inflammation and increasing intestinal permeability.
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Affiliation(s)
- Katharina Brandl
- Skaggs School of Pharmacy, University of California San Diego, 9500 Gilman Drive La Jolla, California 92093-0675, 858-822-6853,
| | - Bernd Schnabl
- Department of Medicine, VA San Diego Healthcare System, San Diego, CA,Department of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0063, University of California San Diego, 858-534-9484,
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216
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Microbial sensing by goblet cells controls immune surveillance of luminal antigens in the colon. Mucosal Immunol 2015; 8:198-210. [PMID: 25005358 PMCID: PMC4268115 DOI: 10.1038/mi.2014.58] [Citation(s) in RCA: 184] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 06/03/2014] [Indexed: 02/07/2023]
Abstract
The delivery of luminal substances across the intestinal epithelium to the immune system is a critical event in immune surveillance, resulting in tolerance to dietary antigens and immunity to pathogens. How this process is regulated is largely unknown. Recently goblet cell-associated antigen passages (GAPs) were identified as a pathway delivering luminal antigens to underlying lamina propria (LP) dendritic cells in the steady state. Here, we demonstrate that goblet cells (GCs) form GAPs in response to acetylcholine (ACh) acting on muscarinic ACh receptor 4. GAP formation in the small intestine was regulated at the level of ACh production, as GCs rapidly formed GAPs in response to ACh analogs. In contrast, colonic GAP formation was regulated at the level of GC responsiveness to ACh. Myd88-dependent microbial sensing by colonic GCs inhibited the ability of colonic GCs to respond to Ach to form GAPs and deliver luminal antigens to colonic LP-antigen-presenting cells (APCs). Disruption of GC microbial sensing in the setting of an intact gut microbiota opened colonic GAPs, and resulted in recruitment of neutrophils and APCs and production of inflammatory cytokines. Thus GC intrinsic sensing of the microbiota has a critical role regulating the exposure of the colonic immune system to luminal substances.
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217
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Jacobs J, Braun J. The Mucosal Microbiome. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00005-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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218
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219
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Rescigno M. Microbial Sensing and Regulation of Mucosal Immune Responses by Intestinal Epithelial Cells. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00028-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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220
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Smith PM, Garrett WS. Gut Microbiota and Intestinal Adaptive Immunity. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00042-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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221
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Zaccard CR, Watkins SC, Kalinski P, Fecek RJ, Yates AL, Salter RD, Ayyavoo V, Rinaldo CR, Mailliard RB. CD40L induces functional tunneling nanotube networks exclusively in dendritic cells programmed by mediators of type 1 immunity. THE JOURNAL OF IMMUNOLOGY 2014; 194:1047-56. [PMID: 25548234 DOI: 10.4049/jimmunol.1401832] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The ability of dendritic cells (DC) to mediate CD4(+) T cell help for cellular immunity is guided by instructive signals received during DC maturation, as well as the resulting pattern of DC responsiveness to the Th signal, CD40L. Furthermore, the professional transfer of antigenic information from migratory DC to lymph node-residing DC is critical for the effective induction of cellular immune responses. In this study we report that, in addition to their enhanced IL-12p70 producing capacity, human DC matured in the presence of inflammatory mediators of type 1 immunity are uniquely programmed to form networks of tunneling nanotube-like structures in response to CD40L-expressing Th cells or rCD40L. This immunologic process of DC reticulation facilitates intercellular trafficking of endosome-associated vesicles and Ag, but also pathogens such HIV-1, and is regulated by the opposing roles of IFN-γ and IL-4. The initiation of DC reticulation represents a novel helper function of CD40L and a superior mechanism of intercellular communication possessed by type 1 polarized DC, as well as a target for exploitation by pathogens to enhance direct cell-to-cell spread.
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Affiliation(s)
- Colleen R Zaccard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Simon C Watkins
- Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Pawel Kalinski
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261; Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15261; Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15261; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261; and
| | - Ronald J Fecek
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Aarika L Yates
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Russell D Salter
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Velpandi Ayyavoo
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Charles R Rinaldo
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261; Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Robbie B Mailliard
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261;
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Feehley T, Nagler CR. Cellular and molecular pathways through which commensal bacteria modulate sensitization to dietary antigens. Curr Opin Immunol 2014; 31:79-86. [PMID: 25458998 PMCID: PMC4255329 DOI: 10.1016/j.coi.2014.10.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 09/25/2014] [Accepted: 10/03/2014] [Indexed: 12/16/2022]
Abstract
Food allergies are a growing public health concern. The rapidly increasing prevalence of allergic disease cannot be explained by genetic variation alone, suggesting a role for gene-by-environment interactions. The bacteria that colonize barrier surfaces, often referred to as the commensal microbiota, are dramatically affected by environmental factors and have a major impact on host health and homeostasis. Increasing evidence suggests that alterations in the composition of the microbiota, caused by factors such as antibiotic use and diet, are contributing to increased sensitization to dietary antigens. This review will discuss the cellular and molecular pathways activated by commensal bacteria to protect against allergic sensitization. By understanding the interplay between the environment, the microbiota, and the host, we may uncover novel therapeutic targets that will allow us to control the allergy epidemic.
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Affiliation(s)
- Taylor Feehley
- Committee on Immunology, Department of Pathology, The University of Chicago, 924 E. 57th St. JFK R120, Chicago, IL 60637, USA
| | - Cathryn R Nagler
- Committee on Immunology, Department of Pathology, The University of Chicago, 924 E. 57th St. JFK R120, Chicago, IL 60637, USA.
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223
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Satoh-Takayama N, Serafini N, Verrier T, Rekiki A, Renauld JC, Frankel G, Di Santo JP. The chemokine receptor CXCR6 controls the functional topography of interleukin-22 producing intestinal innate lymphoid cells. Immunity 2014; 41:776-88. [PMID: 25456160 DOI: 10.1016/j.immuni.2014.10.007] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 10/16/2014] [Indexed: 12/26/2022]
Abstract
Interleukin-22 (IL-22) plays a critical role in mucosal defense, although the molecular mechanisms that ensure IL-22 tissue distribution remain poorly understood. We show that the CXCL16-CXCR6 chemokine-chemokine receptor axis regulated group 3 innate lymphoid cell (ILC3) diversity and function. CXCL16 was constitutively expressed by CX3CR1(+) intestinal dendritic cells (DCs) and coexpressed with IL-23 after Citrobacter rodentium infection. Intestinal ILC3s expressed CXCR6 and its ablation generated a selective loss of the NKp46(+) ILC3 subset, a depletion of intestinal IL-22, and the inability to control C. rodentium infection. CD4(+) ILC3s were unaffected by CXCR6 deficiency and remained clustered within lymphoid follicles. In contrast, the lamina propria of Cxcr6(-/-) mice was devoid of ILC3s. The loss of ILC3-dependent IL-22 epithelial stimulation reduced antimicrobial peptide expression that explained the sensitivity of Cxcr6(-/-) mice to C. rodentium. Our results delineate a critical CXCL16-CXCR6 crosstalk that coordinates the intestinal topography of IL-22 secretion required for mucosal defense.
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Affiliation(s)
- Naoko Satoh-Takayama
- Innate Immunity Unit, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris, France; Inserm U668, 75724 Paris, France.
| | - Nicolas Serafini
- Innate Immunity Unit, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris, France; Inserm U668, 75724 Paris, France
| | - Thomas Verrier
- Innate Immunity Unit, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris, France; Inserm U668, 75724 Paris, France
| | - Abdessalem Rekiki
- Innate Immunity Unit, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris, France; Inserm U668, 75724 Paris, France
| | - Jean-Christophe Renauld
- Ludwig Institute for Cancer Research, Experimental Medicine Unit, Université Catholique de Louvain, Brussels, 1200 Belgium
| | - Gad Frankel
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - James P Di Santo
- Innate Immunity Unit, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris, France; Inserm U668, 75724 Paris, France.
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Abstract
Although intestinal bacteria live deep within the body, they are topographically on the exterior surface and thus outside the host. According to the classic notion that the immune system targets non-self rather than self, these intestinal bacteria should be considered foreign and therefore attacked and eliminated. While this appears to be true for some commensal bacterial species, recent data suggest that the immune system actively becomes tolerant to many bacterial organisms. The induction or activation of regulatory T (Treg) cells that inhibit, rather than promote, inflammatory responses to commensal bacteria appears to be a central component of mucosal tolerance. Loss of this mechanism can lead to inappropriate immune reactivity toward commensal organisms, perhaps contributing to mucosal inflammation characteristic of disorders such as inflammatory bowel disease.
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Affiliation(s)
- Teresa L Ai
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
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225
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Cao S, Feehley TJ, Nagler CR. The role of commensal bacteria in the regulation of sensitization to food allergens. FEBS Lett 2014; 588:4258-66. [PMID: 24791655 PMCID: PMC4216641 DOI: 10.1016/j.febslet.2014.04.026] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 04/24/2014] [Accepted: 04/24/2014] [Indexed: 12/23/2022]
Abstract
The prevalence of life-threatening anaphylactic responses to food is rising at an alarming rate. The emerging role of the gut microbiota in regulating food allergen sensitization may help explain this trend. The mechanisms by which commensal bacteria influence sensitization to dietary antigens are only beginning to be explored. We have found that a population of mucosa-associated commensal anaerobes prevents food allergen sensitization by promoting an IL-22-dependent barrier protective immune response that limits the access of food allergens to the systemic circulation. This early response is followed by an adaptive immune response mediated in part by an expansion of Foxp3(+) Tregs that fortifies the tolerogenic milieu needed to maintain non-responsiveness to food. Bacterial metabolites, such as short-chain fatty acids, may contribute to the process through their ability to promote Foxp3(+) Treg differentiation. This work suggests that environmentally induced alterations of the gut microbiota offset the regulatory signals conferred by protective bacterial species to promote aberrant responses to food. Our research presents exciting new possibilities for preventing and treating food allergies based on interventions that modulate the composition of the gut microbiota.
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Affiliation(s)
- Severine Cao
- Department of Pathology and Committee on Immunology, The University of Chicago, 924 East 57th Street, JFK R120, Chicago, IL 60637, United States
| | - Taylor J Feehley
- Department of Pathology and Committee on Immunology, The University of Chicago, 924 East 57th Street, JFK R120, Chicago, IL 60637, United States
| | - Cathryn R Nagler
- Department of Pathology and Committee on Immunology, The University of Chicago, 924 East 57th Street, JFK R120, Chicago, IL 60637, United States.
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226
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Bowcutt R, Forman R, Glymenaki M, Carding SR, Else KJ, Cruickshank SM. Heterogeneity across the murine small and large intestine. World J Gastroenterol 2014; 20:15216-15232. [PMID: 25386070 PMCID: PMC4223255 DOI: 10.3748/wjg.v20.i41.15216] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 03/18/2014] [Accepted: 06/17/2014] [Indexed: 02/06/2023] Open
Abstract
The small and large intestine of the gastrointestinal tract (GIT) have evolved to have discrete functions with distinct anatomies and immune cell composition. The importance of these differences is underlined when considering that different pathogens have uniquely adapted to live in each region of the gut. Furthermore, different regions of the GIT are also associated with differences in susceptibility to diseases such as cancer and chronic inflammation. The large and small intestine, given their anatomical and functional differences, should be seen as two separate immunological sites. However, this distinction is often ignored with findings from one area of the GIT being inappropriately extrapolated to the other. Focussing largely on the murine small and large intestine, this review addresses the literature relating to the immunology and biology of the two sites, drawing comparisons between them and clarifying similarities and differences. We also highlight the gaps in our understanding and where further research is needed.
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228
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Millet YA, Alvarez D, Ringgaard S, von Andrian UH, Davis BM, Waldor MK. Insights into Vibrio cholerae intestinal colonization from monitoring fluorescently labeled bacteria. PLoS Pathog 2014; 10:e1004405. [PMID: 25275396 PMCID: PMC4183697 DOI: 10.1371/journal.ppat.1004405] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 08/15/2014] [Indexed: 11/18/2022] Open
Abstract
Vibrio cholerae, the agent of cholera, is a motile non-invasive pathogen that colonizes the small intestine (SI). Most of our knowledge of the processes required for V. cholerae intestinal colonization is derived from enumeration of wt and mutant V. cholerae recovered from orogastrically infected infant mice. There is limited knowledge of the distribution of V. cholerae within the SI, particularly its localization along the villous axis, or of the bacterial and host factors that account for this distribution. Here, using confocal and intravital two-photon microscopy to monitor the localization of fluorescently tagged V. cholerae strains, we uncovered unexpected and previously unrecognized features of V. cholerae intestinal colonization. Direct visualization of the pathogen within the intestine revealed that the majority of V. cholerae microcolonies attached to the intestinal epithelium arise from single cells, and that there are notable regiospecific aspects to V. cholerae localization and factors required for colonization. In the proximal SI, V. cholerae reside exclusively within the developing intestinal crypts, but they are not restricted to the crypts in the more distal SI. Unexpectedly, V. cholerae motility proved to be a regiospecific colonization factor that is critical for colonization of the proximal, but not the distal, SI. Furthermore, neither motility nor chemotaxis were required for proper V. cholerae distribution along the villous axis or in crypts, suggesting that yet undefined processes enable the pathogen to find its niches outside the intestinal lumen. Finally, our observations suggest that host mucins are a key factor limiting V. cholerae intestinal colonization, particularly in the proximal SI where there appears to be a more abundant mucus layer. Collectively, our findings demonstrate the potent capacity of direct pathogen visualization during infection to deepen our understanding of host pathogen interactions.
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Affiliation(s)
- Yves A. Millet
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - David Alvarez
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Simon Ringgaard
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ulrich H. von Andrian
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Brigid M. Davis
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Matthew K. Waldor
- Division of Infectious Diseases, Brigham and Women's Hospital, Boston, Massachusetts, United States of America
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America
- Howard Hughes Medical Institute, Boston, Massachusetts, United States of America
- * E-mail:
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229
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Baranov MV, Ter Beest M, van den Bogaart G. Reaching for far-flung antigen: How solid-core podosomes of dendritic cells transform into protrusive structures. Commun Integr Biol 2014; 7:970961. [PMID: 26843902 PMCID: PMC4594491 DOI: 10.4161/cib.29084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 04/28/2014] [Accepted: 04/30/2014] [Indexed: 01/22/2023] Open
Abstract
We recently identified a novel role for podosomes in antigen sampling. Podosomes are dynamic cellular structures that consist of point-like concentrations of actin surrounded by integrins and adaptor proteins such as vinculin and talin. Podosomes establish cellular contact with the extracellular matrix (ECM) and facilitate cell migration via ECM degradation. In our recent paper, we studied podosomes of human dendritic cells (DCs), major antigen presenting cells (APC) that take-up, process, and present foreign antigen to naive T-cells. We employed gelatin-impregnated porous polycarbonate filters to demonstrate that the mechanosensitive podosomes of DCs selectively localize to regions of low-physical resistance such as the filter pores. After degradation of the gelatin, podosomes increasingly protrude into the lumen of these pores. These protrusive podosome-derived structures contain several endocytic and early endosomal markers such as clathrin, Rab5, and VAMP3, and, surprisingly, also contain C-type lectins, a type of pathogen recognition receptors (PRRs). Finally, we performed functional uptake experiments to demonstrate that these PRRs facilitate uptake of antigen from the opposite side of the filter. Our data provide mechanistic insight in how dendritic cells sample for antigen across epithelial barriers for instance from the lumen of the lung and gut.
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Affiliation(s)
- Maksim V Baranov
- Department of Tumor Immunology; Radboud University Medical Center ; Radboud Institute for Molecular Life Sciences ; Nijmegen, The Netherlands
| | - Martin Ter Beest
- Department of Tumor Immunology; Radboud University Medical Center ; Radboud Institute for Molecular Life Sciences ; Nijmegen, The Netherlands
| | - Geert van den Bogaart
- Department of Tumor Immunology; Radboud University Medical Center ; Radboud Institute for Molecular Life Sciences ; Nijmegen, The Netherlands
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230
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Vogt L, Meyer D, Pullens G, Faas M, Smelt M, Venema K, Ramasamy U, Schols HA, De Vos P. Immunological Properties of Inulin-Type Fructans. Crit Rev Food Sci Nutr 2014; 55:414-36. [DOI: 10.1080/10408398.2012.656772] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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231
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Abstract
The intestine represents the largest compartment of the immune system. It is continually exposed to antigens and immunomodulatory agents from the diet and the commensal microbiota, and it is the port of entry for many clinically important pathogens. Intestinal immune processes are also increasingly implicated in controlling disease development elsewhere in the body. In this Review, we detail the anatomical and physiological distinctions that are observed in the small and large intestines, and we suggest how these may account for the diversity in the immune apparatus that is seen throughout the intestine. We describe how the distribution of innate, adaptive and innate-like immune cells varies in different segments of the intestine and discuss the environmental factors that may influence this. Finally, we consider the implications of regional immune specialization for inflammatory disease in the intestine.
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232
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Wiest R, Lawson M, Geuking M. Reply to: "bacterial translocation in liver cirrhosis: site and role in fibrogenesis". J Hepatol 2014; 61:710-1. [PMID: 24929092 DOI: 10.1016/j.jhep.2014.06.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Accepted: 06/08/2014] [Indexed: 12/04/2022]
Affiliation(s)
- Reiner Wiest
- Department Gastroenterology, Inselspital, University Hospital, Bern 3010, Switzerland.
| | - Melissa Lawson
- Maurice Müller Laboratories, Universitätsklinik für Viszerale Chirurgie und Medizin (UVCM), University of Bern, Bern 3010, Switzerland
| | - Markus Geuking
- Maurice Müller Laboratories, Universitätsklinik für Viszerale Chirurgie und Medizin (UVCM), University of Bern, Bern 3010, Switzerland
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233
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Abstract
Clostridium difficile infection (CDI) is the most common infectious cause of healthcare-acquired diarrhoea. Outcomes of C. difficile colonization are varied, from asymptomatic carriage to fulminant colitis and death, due in part to the interplay between the pathogenic virulence factors of the bacterium and the counteractive immune responses of the host. Secreted toxins A and B are the major virulence factors of C. difficile and induce a profound inflammatory response by intoxicating intestinal epithelial cells causing proinflammatory cytokine release. Host cell necrosis, vascular permeability and neutrophil infiltration lead to an elevated white cell count, profuse diarrhoea and in severe cases, dehydration, hypoalbuminaemia and toxic megacolon. Other bacterial virulence factors, including surface layer proteins and flagella proteins, are detected by host cell surface signal molecules that trigger downstream cell-mediated immune pathways. Human studies have identified a role for serum and faecal immunoglobulin levels in protection from disease, but the recent development of a mouse model of CDI has enabled studies into the precise molecular interactions that trigger the immune response during infection. Key effector molecules have been identified that can drive towards a protective anti-inflammatory response or a damaging proinflammatory response. The limitations of current antimicrobial therapies for CDI have led to the development of both active and passive immunotherapies, none of which have, as yet been formally approved for CDI. However, recent advances in our understanding of the molecular basis of host immune protection against CDI may provide an exciting opportunity for novel therapeutic developments in the future.
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Affiliation(s)
- Katie Solomon
- School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Republic of Ireland
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234
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Exploring the influence of the gut microbiota and probiotics on health: a symposium report. Br J Nutr 2014; 112 Suppl 1:S1-18. [PMID: 24953670 PMCID: PMC4077244 DOI: 10.1017/s0007114514001275] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The present report describes the presentations delivered at the 7th International Yakult Symposium, ‘The Intestinal Microbiota and Probiotics: Exploiting Their Influence on Health’, in London on 22–23 April 2013. The following two themes associated with health risks were covered: (1) the impact of age and diet on the gut microbiota and (2) the gut microbiota's interaction with the host. The strong influence of the maternal gut microbiota on neonatal colonisation was reported, as well as rapid changes in the gut microbiome of older people who move from community living to residential care. The effects of dietary changes on gut metabolism were described and the potential influence of inter-individual microbiota differences was noted, in particular the presence/absence of keystone species involved in butyrate metabolism. Several speakers highlighted the association between certain metabolic disorders and imbalanced or less diverse microbiota. Data from metagenomic analyses and novel techniques (including an ex vivo human mucosa model) provided new insights into the microbiota's influence on coeliac, obesity-related and inflammatory diseases, as well as the potential of probiotics. Akkermansia muciniphila and Faecalibacterium prausnitzii were suggested as targets for intervention. Host–microbiota interactions were explored in the context of gut barrier function, pathogenic bacteria recognition, and the ability of the immune system to induce either tolerogenic or inflammatory responses. There was speculation that the gut microbiota should be considered a separate organ, and whether analysis of an individual's microbiota could be useful in identifying their disease risk and/or therapy; however, more research is needed into specific diseases, different population groups and microbial interventions including probiotics.
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235
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Pontier-Bres R, Munro P, Boyer L, Anty R, Imbert V, Terciolo C, André F, Rampal P, Lemichez E, Peyron JF, Czerucka D. Saccharomyces boulardii modifies Salmonella typhimurium traffic and host immune responses along the intestinal tract. PLoS One 2014; 9:e103069. [PMID: 25118595 PMCID: PMC4145484 DOI: 10.1371/journal.pone.0103069] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 06/27/2014] [Indexed: 12/12/2022] Open
Abstract
Salmonella enterica serovar Typhimurium (ST) is an enteropathogenic Gram-negative bacterium that causes infection following oral ingestion. ST spreads rapidly along the gastrointestinal tract (GIT) and invades the intestinal epithelium to ultimately reach internal body organs. The probiotic yeast Saccharomyces boulardii BIOCODEX (S.b-B) is prescribed for prophylaxis of diarrheal infectious diseases. We previously showed that S.b-B prevents weight loss in ST-infected mice and significantly decreases bacterial translocation to the spleen and liver. This study was designed to investigate the effect of S.b-B on ST migration along the GIT and the impact of the yeast on the host's early innate immune responses. Bioluminescent imaging (BLI) was used to evaluate the effect of S.b-B on the progression of luminescent Salmonella Typhimurium (ST-lux) in the GIT of mice pretreated with streptomycin. Photonic emission (PE) was measured in GIT extracts (stomach, small intestine, cecum and colon) at various time periods post-infection (PI). PE analysis revealed that, 45 min PI, ST-lux had migrated slightly faster in the mice treated with S.b-B than in the untreated infected animals. At 90 min PI, ST-lux had reached the cecum in both groups of mice. Adhesion of ST to S.b-B was visualized in the intestines of the mice and probably accounts for (1) the faster elimination of ST-lux in the feces, and (2) reduced translocation of ST to the spleen and liver. In the early phase of infection, S.b-B also modifies the host's immune responses by (1) increasing IFN-γ gene expression and decreasing IL-10 gene expression in the small intestine, and (2) elevating both IFN-γ, and IL-10 mRNA levels in the cecum. BLI revealed that S.b-B modifies ST migration and the host immune response along the GIT. Study findings shed new light on the protective mechanisms of S.b-B during the early phase of Salmonella pathogenesis.
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Affiliation(s)
- Rodolphe Pontier-Bres
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 4 “Inflammation, Cancer, Cancer Stem Cells” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
| | - Patrick Munro
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 6 “Microbial toxins in host pathogen interactions” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
| | - Laurent Boyer
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 6 “Microbial toxins in host pathogen interactions” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
| | - Rodolphe Anty
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 8 “Hepatic complications in obesity” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
| | - Véronique Imbert
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 4 “Inflammation, Cancer, Cancer Stem Cells” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
| | - Chloé Terciolo
- CRO2 INSERM U911, Campus Santé Timone, Université Aix-Marseille, Marseille, France
| | - Fréderic André
- CRO2 INSERM U911, Campus Santé Timone, Université Aix-Marseille, Marseille, France
| | | | - Emmanuel Lemichez
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 6 “Microbial toxins in host pathogen interactions” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
| | - Jean-François Peyron
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 4 “Inflammation, Cancer, Cancer Stem Cells” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
| | - Dorota Czerucka
- INSERM, U1065, Centre Méditerranéen de Médecine Moléculaire (C3M), Team 4 “Inflammation, Cancer, Cancer Stem Cells” Nice, France
- Université de Nice-Sophia Antipolis, UFR Médecine, IFR50, Faculté de Médecine, Nice, France
- * E-mail:
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236
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Mann ER, Li X. Intestinal antigen-presenting cells in mucosal immune homeostasis: Crosstalk between dendritic cells, macrophages and B-cells. World J Gastroenterol 2014; 20:9653-9664. [PMID: 25110405 PMCID: PMC4123356 DOI: 10.3748/wjg.v20.i29.9653] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 02/26/2014] [Accepted: 04/29/2014] [Indexed: 02/06/2023] Open
Abstract
The intestinal immune system maintains a delicate balance between immunogenicity against invading pathogens and tolerance of the commensal microbiota. Inflammatory bowel disease (IBD) involves a breakdown in tolerance towards the microbiota. Dendritic cells (DC), macrophages (MΦ) and B-cells are known as professional antigen-presenting cells (APC) due to their specialization in presenting processed antigen to T-cells, and in turn shaping types of T-cell responses generated. Intestinal DC are migratory cells, unique in their ability to generate primary T-cell responses in mesenteric lymph nodes or Peyer’s patches, whilst MΦ and B-cells contribute to polarization and differentiation of secondary T-cell responses in the gut lamina propria. The antigen-sampling function of gut DC and MΦ enables them to sample bacterial antigens from the gut lumen to determine types of T-cell responses generated. The primary function of intestinal B-cells involves their secretion of large amounts of immunoglobulin A, which in turn contributes to epithelial barrier function and limits immune responses towards to microbiota. Here, we review the role of all three types of APC in intestinal immunity, both in the steady state and in inflammation, and how these cells interact with one another, as well as with the intestinal microenvironment, to shape mucosal immune responses. We describe mechanisms of maintaining intestinal immune tolerance in the steady state but also inappropriate responses of APC to components of the gut microbiota that contribute to pathology in IBD.
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237
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Abstract
The human fetus lives in a germ-free intrauterine environment and enters the outside world containing microorganisms from several sources, resulting in gut colonization. Full-term, vaginally born infants are completely colonized with a diverse array of bacterial families in clusters (Phyla) and species (>1000) by the first year of life. Colonizing bacteria communicating with the gut epithelium and underlying lymphoid tissues ('bacterial-epithelial crosstalk') result in a functional immune phenotype and no expression of disease (immune homeostasis). Appropriate colonization is influenced by the prebiotic effect of breast milk oligosaccharides. Adequate colonization results in an innate and adaptive mucosal immune phenotype via communication between molecular patterns on colonizing bacteria and pattern-recognition receptors (e.g., toll-like receptors) on epithelial and lymphoid cells. This ontogeny affects the immune system's capacity to develop oral tolerance to innocuous bacteria and benign antigens. Inadequate intestinal colonization with premature delivery, delivery by Cesarean section and excessive use of perinatal antibiotics results in the absence of adequate bacterial-epithelial crosstalk and an increased incidence of immune-mediated diseases [e.g., asthma, allergy in general and necrotizing enterocolitis (NEC)]. Fortunately, infants with inadequate intestinal colonization can be restored to a bacterial balance with the intake of probiotics. This has been shown to prevent debilitating diseases such as NEC. Thus, understanding the role of gut microbiota in programming of the immune phenotype may be important in preventing disease expression in later childhood and adulthood.
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238
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Benechet AP, Menon M, Khanna KM. Visualizing T Cell Migration in situ. Front Immunol 2014; 5:363. [PMID: 25120547 PMCID: PMC4114210 DOI: 10.3389/fimmu.2014.00363] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Accepted: 07/14/2014] [Indexed: 12/16/2022] Open
Abstract
Mounting a protective immune response is critically dependent on the orchestrated movement of cells within lymphoid tissues. The structure of secondary lymphoid organs regulates immune responses by promoting optimal cell-cell and cell-extracellular matrix interactions. Naïve T cells are initially activated by antigen presenting cells in secondary lymphoid organs. Following priming, effector T cells migrate to the site of infection to exert their functions. Majority of the effector cells die while a small population of antigen-specific T cells persists as memory cells in distinct anatomical locations. The persistence and location of memory cells in lymphoid and non-lymphoid tissues is critical to protect the host from re-infection. The localization of memory T cells is carefully regulated by several factors including the highly organized secondary lymphoid structure, the cellular expression of chemokine receptors and compartmentalized secretion of their cognate ligands. This balance between the anatomy and the ordered expression of cell surface and soluble proteins regulates the subtle choreography of T cell migration. In recent years, our understanding of cellular dynamics of T cells has been advanced by the development of new imaging techniques allowing in situ visualization of T cell responses. Here, we review the past and more recent studies that have utilized sophisticated imaging technologies to investigate the migration dynamics of naïve, effector, and memory T cells.
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Affiliation(s)
- Alexandre P. Benechet
- Department of Immunology, University of Connecticut Health Center, Farmington, CT, USA
| | - Manisha Menon
- Department of Immunology, University of Connecticut Health Center, Farmington, CT, USA
| | - Kamal M. Khanna
- Department of Immunology, University of Connecticut Health Center, Farmington, CT, USA
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239
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Spasova DS, Surh CD. Blowing on embers: commensal microbiota and our immune system. Front Immunol 2014; 5:318. [PMID: 25120539 PMCID: PMC4112811 DOI: 10.3389/fimmu.2014.00318] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 06/24/2014] [Indexed: 12/19/2022] Open
Abstract
Vertebrates have co-evolved with microorganisms resulting in a symbiotic relationship, which plays an important role in health and disease. Skin and mucosal surfaces are colonized with a diverse population of commensal microbiota, over 1000 species, outnumbering the host cells by 10-fold. In the past 40 years, studies have built on the idea that commensal microbiota is in constant contact with the host immune system and thus influence immune function. Recent studies, focusing on mutualism in the gut, have shown that commensal microbiota seems to play a critical role in the development and homeostasis of the host immune system. In particular, the gut microbiota appears to direct the organization and maturation of lymphoid tissues and acts both locally and systemically to regulate the recruitment, differentiation, and function of innate and adaptive immune cells. While the pace of research in the area of the mucosal–immune interface has certainly intensified over the last 10 years, we are still in the early days of this field. Illuminating the mechanisms of how gut microbes shape host immunity will enhance our understanding of the causes of immune-mediated pathologies and improve the design of next-generation vaccines. This review discusses the recent advances in this field, focusing on the close relationship between the adaptive immune system and commensal microbiota, a constant and abundant source of foreign antigens.
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Affiliation(s)
- Darina S Spasova
- Kellog School of Science and Technology Doctoral Program in Chemical and Biological Sciences and the Department of Immunology and Microbial Science, The Scripps Research Institute , La Jolla, CA , USA ; Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology , La Jolla, CA , USA
| | - Charles D Surh
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology , La Jolla, CA , USA ; Academy of Immunology and Microbiology, Institute of Basic Science , Pohang , South Korea ; Department of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology , Pohang , South Korea
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240
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Menter DG, Patterson SL, Logsdon CD, Kopetz S, Sood AK, Hawk ET. Convergence of nanotechnology and cancer prevention: are we there yet? Cancer Prev Res (Phila) 2014; 7:973-92. [PMID: 25060262 DOI: 10.1158/1940-6207.capr-14-0079] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Nanotechnology is emerging as a promising modality for cancer treatment; however, in the realm of cancer prevention, its full utility has yet to be determined. Here, we discuss the potential of integrating nanotechnology in cancer prevention to augment early diagnosis, precision targeting, and controlled release of chemopreventive agents, reduced toxicity, risk/response assessment, and personalized point-of-care monitoring. Cancer is a multistep, progressive disease; the functional and acquired characteristics of the early precancer phenotype are intrinsically different from those of a more advanced anaplastic or invasive malignancy. Therefore, applying nanotechnology to precancers is likely to be far more challenging than applying it to established disease. Frank cancers are more readily identifiable through imaging and biomarker and histopathologic assessment than their precancerous precursors. In addition, prevention subjects routinely have more rigorous intervention criteria than therapy subjects. Any nanopreventive agent developed to prevent sporadic cancers found in the general population must exhibit a very low risk of serious side effects. In contrast, a greater risk of side effects might be more acceptable in subjects at high risk for cancer. Using nanotechnology to prevent cancer is an aspirational goal, but clearly identifying the intermediate objectives and potential barriers is an essential first step in this exciting journey.
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Affiliation(s)
- David G Menter
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Sherri L Patterson
- Division of Cancer Prevention & Population Sciences, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Craig D Logsdon
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Scott Kopetz
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Anil K Sood
- Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Ernest T Hawk
- Division of Cancer Prevention & Population Sciences, The University of Texas MD Anderson Cancer Center, Houston, Texas.
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241
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Zhao Y, Zhao W, Lang G, Chen Y, Liu J, Wang G, Ma X, Gong M, Xu D, Xia S. Circumcision plus antibiotic, anti-inflammatory, and α-blocker therapy for the treatment for chronic prostatitis/chronic pelvic pain syndrome: a prospective, randomized, multicenter trial. World J Urol 2014; 33:617-22. [DOI: 10.1007/s00345-014-1350-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 06/16/2014] [Indexed: 12/14/2022] Open
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242
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Kim TH, Lee HK. Differential roles of lung dendritic cell subsets against respiratory virus infection. Immune Netw 2014; 14:128-37. [PMID: 24999309 PMCID: PMC4079819 DOI: 10.4110/in.2014.14.3.128] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 05/22/2014] [Accepted: 05/27/2014] [Indexed: 01/21/2023] Open
Abstract
Respiratory viruses can induce acute respiratory disease. Clinical symptoms and manifestations are dependent on interactions between the virus and host immune system. Dendritic cells (DCs), along with alveolar macrophages, constitute the first line of sentinel cells in the innate immune response against respiratory viral infection. DCs play an essential role in regulating the immune response by bridging innate and adaptive immunity. In the steady state, lung DCs can be subdivided into CD103+ conventional DCs (cDCs), CD11b+ cDCs, and plasmacytoid DCs (pDCs). In the inflammatory state, like a respiratory viral infection, monocyte-derived DCs (moDCs) are recruited to the lung. In inflammatory lung, discrimination between moDCs and CD11b+ DCs in the inflamed lung has been a critical challenge in understanding their role in the antiviral response. In particular, CD103+ cDCs migrate from the intraepithelial base to the draining mediastinal lymph nodes to primarily induce the CD8+ T cell response against the invading virus. Lymphoid CD8α+ cDCs, which have a developmental relationship with CD103+ cDCs, also play an important role in viral antigen presentation. Moreover, pDCs have been reported to promote an antiviral response by inducing type I interferon production rather than adaptive immunity. However, the role of these cells in respiratory infections remains unclear. These different DC subsets have functional specialization against respiratory viral infection. Under certain viral infection, contextually controlling the balance of these specialized DC subsets is important for an effective immune response and maintenance of homeostasis.
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Affiliation(s)
- Tae Hoon Kim
- Laboratory of Host Defenses, Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Korea
| | - Heung Kyu Lee
- Laboratory of Host Defenses, Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Korea
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243
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Skoczek DA, Walczysko P, Horn N, Parris A, Clare S, Williams MR, Sobolewski A. Luminal microbes promote monocyte-stem cell interactions across a healthy colonic epithelium. THE JOURNAL OF IMMUNOLOGY 2014; 193:439-51. [PMID: 24907348 PMCID: PMC4067517 DOI: 10.4049/jimmunol.1301497] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The intestinal epithelium forms a vital barrier between luminal microbes and the underlying mucosal immune system. Epithelial barrier function is maintained by continuous renewal of the epithelium and is pivotal for gut homeostasis. Breaching of the barrier causes mobilization of immune cells to promote epithelial restitution. However, it is not known whether microbes at the luminal surface of a healthy epithelial barrier influence immune cell mobilization to modulate tissue homeostasis. Using a mouse colonic mucosal explant model, we demonstrate that close proximity of luminal microbes to a healthy, intact epithelium results in rapid mucus secretion and movement of Ly6C+7/4+ monocytes closer to epithelial stem cells. These early events are driven by the epithelial MyD88-signaling pathway and result in increased crypt cell proliferation and intestinal stem cell number. Over time, stem cell number and monocyte–crypt stem cell juxtapositioning return to homeostatic levels observed in vivo. We also demonstrate that reduced numbers of tissue Ly6C+ monocytes can suppress Lgr5EGFP+ stem cell expression in vivo and abrogate the response to luminal microbes ex vivo. The functional link between monocyte recruitment and increased crypt cell proliferation was further confirmed using a crypt–monocyte coculture model. This work demonstrates that the healthy gut epithelium mediates communication between luminal bacteria and monocytes, and monocytes can modulate crypt stem cell number and promote crypt cell proliferation to help maintain gut homeostasis.
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Affiliation(s)
- Dagmara A Skoczek
- Gut Health and Food Safety Institute Strategic Program, Institute of Food Research, Norwich, Norfolk NR4 7UA, United Kingdom
| | - Petr Walczysko
- Gut Health and Food Safety Institute Strategic Program, Institute of Food Research, Norwich, Norfolk NR4 7UA, United Kingdom
| | - Nikki Horn
- Gut Health and Food Safety Institute Strategic Program, Institute of Food Research, Norwich, Norfolk NR4 7UA, United Kingdom
| | - Alyson Parris
- School of Biological Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, United Kingdom; and
| | - Simon Clare
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, Cambridgeshire CB10 1SA, United Kingdom
| | - Mark R Williams
- School of Biological Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, United Kingdom; and
| | - Anastasia Sobolewski
- Gut Health and Food Safety Institute Strategic Program, Institute of Food Research, Norwich, Norfolk NR4 7UA, United Kingdom;
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244
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Belkaid Y, Hand TW. Role of the microbiota in immunity and inflammation. Cell 2014; 157:121-41. [PMID: 24679531 DOI: 10.1016/j.cell.2014.03.011] [Citation(s) in RCA: 3034] [Impact Index Per Article: 303.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/10/2014] [Accepted: 03/11/2014] [Indexed: 02/06/2023]
Abstract
The microbiota plays a fundamental role on the induction, training, and function of the host immune system. In return, the immune system has largely evolved as a means to maintain the symbiotic relationship of the host with these highly diverse and evolving microbes. When operating optimally, this immune system-microbiota alliance allows the induction of protective responses to pathogens and the maintenance of regulatory pathways involved in the maintenance of tolerance to innocuous antigens. However, in high-income countries, overuse of antibiotics, changes in diet, and elimination of constitutive partners, such as nematodes, may have selected for a microbiota that lack the resilience and diversity required to establish balanced immune responses. This phenomenon is proposed to account for some of the dramatic rise in autoimmune and inflammatory disorders in parts of the world where our symbiotic relationship with the microbiota has been the most affected.
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Affiliation(s)
- Yasmine Belkaid
- Immunity at Barrier Sites Initiative, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Timothy W Hand
- Immunity at Barrier Sites Initiative, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; Mucosal Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD 20892, USA
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245
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Corridoni D, Arseneau KO, Cominelli F. Inflammatory bowel disease. Immunol Lett 2014; 161:231-5. [PMID: 24938525 DOI: 10.1016/j.imlet.2014.04.004] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 04/01/2014] [Indexed: 12/13/2022]
Abstract
Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are chronic, relapsing inflammatory condition of the gastrointestinal tract. CD and UC have distinct pathologic and clinical characteristics and despite the extensive amount of research conducted over the past decades, their pathogenesis remains still poorly understood. So far, the accepted dogma is that IBD results from dysregulated mucosal immune response to environmental factors in genetical susceptible hosts. Various components are implicated in the pathogenesis of IBD, including genetic susceptibility, environmental and microbial factors, intestinal epithelial cells and components of innate and adaptive immune system. Given the complexity of IBD, several different animal models of IBD have been developed during the last years. Animal models are very important tools to study the involvement of various factors in the pathogenesis of IBD and, importantly, to test new therapeutic options. This review examines some of the key components that have been found to be closely associated to IBD and describe the distinct features of some of the most important IBD models.
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Affiliation(s)
- Daniele Corridoni
- Department of Medicine, Case Western Reserve University, Cleveland, OH, USA; Digestive Health Research Center, Case Western Reserve University, Cleveland, OH, USA
| | - Kristen O Arseneau
- Department of Medicine, Case Western Reserve University, Cleveland, OH, USA; Digestive Health Research Center, Case Western Reserve University, Cleveland, OH, USA
| | - Fabio Cominelli
- Department of Medicine, Case Western Reserve University, Cleveland, OH, USA; Digestive Health Research Center, Case Western Reserve University, Cleveland, OH, USA.
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246
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Villena J, Chiba E, Vizoso-Pinto MG, Tomosada Y, Takahashi T, Ishizuka T, Aso H, Salva S, Alvarez S, Kitazawa H. Immunobiotic Lactobacillus rhamnosus strains differentially modulate antiviral immune response in porcine intestinal epithelial and antigen presenting cells. BMC Microbiol 2014; 14:126. [PMID: 24886142 PMCID: PMC4035899 DOI: 10.1186/1471-2180-14-126] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 05/07/2014] [Indexed: 01/24/2023] Open
Abstract
Background Previous findings suggested that Lactobacillus rhamnosus CRL1505 is able to increase resistance of children to intestinal viral infections. However, the intestinal cells, cytokines and receptors involved in the immunoregulatory effect of this probiotic strain have not been fully characterized. Results We aimed to gain insight into the mechanisms involved in the immunomodulatory effect of the CRL1505 strain and therefore evaluated in vitro the crosstalk between L. rhamnosus CRL1505, porcine intestinal epithelial cells (IECs) and antigen presenting cells (APCs) from swine Peyer’s patches in order to deepen our knowledge about the mechanisms, through which this strain may help preventing viral diarrhoea episodes. L. rhamnosus CRL1505 was able to induce IFN–α and –β in IECs and improve the production of type I IFNs in response to poly(I:C) challenge independently of Toll-like receptor (TLR)-2 or TLR9 signalling. In addition, the CRL1505 strain induced mRNA expression of IL-6 and TNF-α via TLR2 in IECs. Furthermore, the strain significantly increased surface molecules expression and cytokine production in intestinal APCs. The improved Th1 response induced by L. rhamnosus CRL1505 was triggered by TLR2 signalling and included augmented expression of MHC-II and co-stimulatory molecules and expression of IL-1β, IL-6, and IFN-γ in APCs. IL-10 was also significantly up-regulated by CRL1505 in APCs. Conclusions It was recently reviewed the emergence of TLR agonists as new ways to transform antiviral treatments by introducing panviral therapeutics with less adverse effects than IFN therapies. The use of L. rhamnosus CRL1505 as modulator of innate immunity and inductor of antiviral type I IFNs, IFN-γ, and regulatory IL-10 clearly offers the potential to overcome this challenge.
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Affiliation(s)
- Julio Villena
- Food and Feed Immunology Group, Laboratory of Animal Products Chemistry, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan.
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Heuzé ML, Vargas P, Chabaud M, Le Berre M, Liu YJ, Collin O, Solanes P, Voituriez R, Piel M, Lennon-Duménil AM. Migration of dendritic cells: physical principles, molecular mechanisms, and functional implications. Immunol Rev 2014; 256:240-54. [PMID: 24117825 DOI: 10.1111/imr.12108] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Dendritic cells (DCs) constitute a complex cell population that resides in both peripheral tissues and lymphoid organs. Their major function in tissues is to patrol their environment in search of danger-associated antigens to transport to lymph nodes and present to T lymphocytes. This process constitutes the first step of the adaptive immune response and relies on specific DC properties, including a high endocytic capacity as well as efficient motility in confined three-dimensional environments. Although cell motility has been widely studied, little is known on how the geometric characteristics of the environment influence DC migration and function. In this review, we give an overview of the basic physical principles and molecular mechanisms that control DC migration under confinement and discuss how such mechanisms impact the environment-patrolling capacity of DCs.
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248
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Russo E, Nitschké M, Halin C. Dendritic cell interactions with lymphatic endothelium. Lymphat Res Biol 2014; 11:172-82. [PMID: 24044757 DOI: 10.1089/lrb.2013.0008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Afferent lymphatic vessels fulfill essential immune functions by transporting leukocytes and lymph-borne antigen to draining lymph nodes (dLNs). An important cell type migrating through lymphatic vessels are dendritic cells (DCs). DCs reside in peripheral tissues like the skin, where they take up antigen and transport it via the lymphatic vascular network to dLNs for subsequent presentation to T cells. As such, DCs play a key role in the induction of adaptive immune responses during infection and vaccination, but also for the maintenance of tolerance. Although the migratory pattern of DCs has been known for long time, interactions between DCs and lymphatic vessels are only now starting to be unraveled at the cellular level. In particular, new tools for visualizing lymphatic vessels in combination with time-lapse microscopy have recently generated valuable insights into the process of DC migration to dLNs. In this review we summarize and discuss current approaches for visualizing DCs and lymphatic vessels in tissues for imaging applications. Furthermore, we review the current state of knowledge about DC migration towards, into and within lymphatic vessels, particularly focusing on the cellular interactions that take place between DCs and the lymphatic endothelium.
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Affiliation(s)
- Erica Russo
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology , ETH Zurich, Switzerland
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249
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CX3CR1⁺ cells facilitate the activation of CD4 T cells in the colonic lamina propria during antigen-driven colitis. Mucosal Immunol 2014; 7:533-48. [PMID: 24129164 DOI: 10.1038/mi.2013.70] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 08/14/2013] [Indexed: 02/04/2023]
Abstract
Dendritic cells (DCs) and macrophages populate the intestinal lamina propria to initiate immune responses required for the maintenance of intestinal homeostasis. To investigate whether CX3CR1(+) phagocytes communicate with CD4 T cells during the development of transfer colitis, we established an antigen-driven colitis model induced by the adoptive transfer of DsRed OT-II cells in CX3CR1(GFP/+) × RAG(-/-) recipients challenged with Escherichia coli expressing ovalbumin (OVA) fused to a cyan fluorescent protein (CFP). After colonization of CX3CR1(GFP/+) × RAG(-/-) animals with red fluorescent E. coli pCherry-OVA, colonic CX3CR1(+) cells but not CD103(+) DCs phagocytosed E. coli pCherry-OVA. Degraded bacterial-derived antigens are transported by CD103(+) DCs to mesenteric lymph nodes (MLNs), where CD103(+) DCs prime naive T cells. In RAG(-/-) recipients reconstituted with OT II cells and gavaged with OVA-expressing E. coli, colonic CX3CR1(+) phagocytes are in close contact with CD4 T cells and presented bacterial-derived antigens to CD4 T cells to activate and expand effector T cells.
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250
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Rescigno M. Intestinal microbiota and its effects on the immune system. Cell Microbiol 2014; 16:1004-13. [PMID: 24720613 DOI: 10.1111/cmi.12301] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2014] [Indexed: 12/11/2022]
Abstract
The microbiota colonizes every surface exposed to the external world and in the gut, it plays important roles in physiological functions such as the maturation of the immune system, the degradation of complex food macromolecules and also behaviour. As such, the immune system has developed tools to cohabit with the microbiota, but also to keep it under control. When this control is lost, dysbiosis, i.e. deregulation in bacterial communities, can occur and this can lead to inflammatory disorders, including inflammatory bowel disease, obesity, diabetes and autism. For these reasons, the analysis of the microbiota, its interactions with the host and its composition in disease, have been intensively investigated in the last few years. In this review, we summarize the major findings in the interaction of the microbiota with the host immune system.
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Affiliation(s)
- Maria Rescigno
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
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