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Beyond the Matrix: The Many Non-ECM Ligands for Integrins. Int J Mol Sci 2018; 19:ijms19020449. [PMID: 29393909 PMCID: PMC5855671 DOI: 10.3390/ijms19020449] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 01/21/2018] [Accepted: 01/30/2018] [Indexed: 12/17/2022] Open
Abstract
The traditional view of integrins portrays these highly conserved cell surface receptors as mediators of cellular attachment to the extracellular matrix (ECM), and to a lesser degree, as coordinators of leukocyte adhesion to the endothelium. These canonical activities are indispensable; however, there is also a wide variety of integrin functions mediated by non-ECM ligands that transcend the traditional roles of integrins. Some of these unorthodox roles involve cell-cell interactions and are engaged to support immune functions such as leukocyte transmigration, recognition of opsonization factors, and stimulation of neutrophil extracellular traps. Other cell-cell interactions mediated by integrins include hematopoietic stem cell and tumor cell homing to target tissues. Integrins also serve as cell-surface receptors for various growth factors, hormones, and small molecules. Interestingly, integrins have also been exploited by a wide variety of organisms including viruses and bacteria to support infectious activities such as cellular adhesion and/or cellular internalization. Additionally, the disruption of integrin function through the use of soluble integrin ligands is a common strategy adopted by several parasites in order to inhibit blood clotting during hematophagy, or by venomous snakes to kill prey. In this review, we strive to go beyond the matrix and summarize non-ECM ligands that interact with integrins in order to highlight these non-traditional functions of integrins.
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52
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Huckaby JT, Lai SK. PEGylation for enhancing nanoparticle diffusion in mucus. Adv Drug Deliv Rev 2018; 124:125-139. [PMID: 28882703 DOI: 10.1016/j.addr.2017.08.010] [Citation(s) in RCA: 230] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 08/29/2017] [Accepted: 08/30/2017] [Indexed: 02/07/2023]
Abstract
The viscoelastic mucus secretions coating exposed organs such as the lung airways and the female reproductive tract can trap and quickly eliminate not only foreign pathogens and ultrafine particles but also particle-based drug delivery systems, thus limiting sustained and targeted drug delivery at mucosal surfaces. To improve particle distribution across the mucosa and enhance delivery to the underlying epithelium, many investigators have sought to develop nanoparticles capable of readily traversing mucus. The first synthetic nanoparticles shown capable of rapidly penetrating physiological mucus secretions utilized a dense coating of polyethylene glycol (PEG) covalently grafted onto the surface of preformed polymeric nanoparticles. In the decade since, PEG has become the gold standard in engineering mucus-penetrating drug carriers for sustained and targeted drug delivery to the lungs, gastrointestinal tract, eyes, and female reproductive tract. This review summarizes the history of the development of various PEG-based mucus-penetrating particles, and highlights the key physicochemical properties of PEG coatings and PEGylation strategies to achieve muco-inert PEG coatings on nanoparticle drug carriers for improved drug and gene delivery at mucosal surfaces.
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54
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Kim J, Fukuto HS, Brown DA, Bliska JB, London E. Effects of host cell sterol composition upon internalization of Yersinia pseudotuberculosis and clustered β1 integrin. J Biol Chem 2017; 293:1466-1479. [PMID: 29197826 DOI: 10.1074/jbc.m117.811224] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 11/29/2017] [Indexed: 11/06/2022] Open
Abstract
Yersinia pseudotuberculosis is a foodborne pathogenic bacterium that causes acute gastrointestinal illness, but its mechanisms of infection are incompletely described. We examined how host cell sterol composition affected Y. pseudotuberculosis uptake. To do this, we depleted or substituted cholesterol in human MDA-MB-231 epithelial cells with various alternative sterols. Decreasing host cell cholesterol significantly reduced pathogen internalization. When host cell cholesterol was substituted with various sterols, only desmosterol and 7-dehydrocholesterol supported internalization. This specificity was not due to sterol dependence of bacterial attachment to host cells, which was similar with all sterols studied. Because a key step in Y. pseudotuberculosis internalization is interaction of the bacterial adhesins invasin and YadA with host cell β1 integrin, we compared the sterol dependence of wildtype Y. pseudotuberculosis internalization with that of Δinv, ΔyadA, and ΔinvΔyadA mutant strains. YadA deletion decreased bacterial adherence to host cells, whereas invasin deletion had no effect. Nevertheless, host cell sterol substitution had a similar effect on internalization of these bacterial deletion strains as on the wildtype bacteria. The ΔinvΔyadA double mutant adhered least to cells and so was not significantly internalized. The sterol structure dependence of Y. pseudotuberculosis internalization differed from that of endocytosis, as monitored using antibody-clustered β1 integrin and previous studies on other proteins, which had a more permissive sterol dependence. This study suggests that agents could be designed to interfere with internalization of Yersinia without disturbing endocytosis.
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Affiliation(s)
- JiHyun Kim
- From the Departments of Biochemistry and Cell Biology and
| | - Hana S Fukuto
- Molecular Genetics and Microbiology and.,Center for Infectious Diseases, Stony Brook University, Stony Brook, New York 11794
| | | | - James B Bliska
- Molecular Genetics and Microbiology and.,Center for Infectious Diseases, Stony Brook University, Stony Brook, New York 11794
| | - Erwin London
- From the Departments of Biochemistry and Cell Biology and
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55
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Kimura S. Molecular insights into the mechanisms of M-cell differentiation and transcytosis in the mucosa-associated lymphoid tissues. Anat Sci Int 2017; 93:23-34. [PMID: 29098649 DOI: 10.1007/s12565-017-0418-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 10/13/2017] [Indexed: 02/07/2023]
Abstract
Microfold cells (M cells), which are located in the follicle-associated epithelium (FAE) covering mucosal lymphoid follicles, are specialized epithelial cells that initiate mucosal immune responses. These cells take luminal antigens and transport them via transcytosis across the FAE to the antigen-presenting cells underneath. Several intestinal pathogens exploit M cells as their portal for entry to invade the host and cause disease conditions. Recent studies have revealed that the uptake of antigens by M cells is essential for efficient antigen-specific IgA production and that this process likely maintains the homeostasis of mucosal tissues. The present article reviews recent advances in understanding the molecular mechanism of M-cell differentiation and describes the molecules expressed by M cells that are associated with antigen uptake and/or the transcytosis process. Current efforts to augment M-cell-mediated uptake for use in the development of effective mucosal vaccines are also discussed.
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Affiliation(s)
- Shunsuke Kimura
- Laboratory of Histology and Cytology, Graduate School of Medicine, Hokkaido University, North 15, West 7, Kita-ku, Sapporo, 060-8638, Japan.
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56
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Da Silva C, Wagner C, Bonnardel J, Gorvel JP, Lelouard H. The Peyer's Patch Mononuclear Phagocyte System at Steady State and during Infection. Front Immunol 2017; 8:1254. [PMID: 29038658 PMCID: PMC5630697 DOI: 10.3389/fimmu.2017.01254] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/20/2017] [Indexed: 12/14/2022] Open
Abstract
The gut represents a potential entry site for a wide range of pathogens including protozoa, bacteria, viruses, or fungi. Consequently, it is protected by one of the largest and most diversified population of immune cells of the body. Its surveillance requires the constant sampling of its encounters by dedicated sentinels composed of follicles and their associated epithelium located in specialized area. In the small intestine, Peyer’s patches (PPs) are the most important of these mucosal immune response inductive sites. Through several mechanisms including transcytosis by specialized epithelial cells called M-cells, access to the gut lumen is facilitated in PPs. Although antigen sampling is critical to the initiation of the mucosal immune response, pathogens have evolved strategies to take advantage of this permissive gateway to enter the host and disseminate. It is, therefore, critical to decipher the mechanisms that underlie both host defense and pathogen subversive strategies in order to develop new mucosal-based therapeutic approaches. Whereas penetration of pathogens through M cells has been well described, their fate once they have reached the subepithelial dome (SED) remains less well understood. Nevertheless, it is clear that the mononuclear phagocyte system (MPS) plays a critical role in handling these pathogens. MPS members, including both dendritic cells and macrophages, are indeed strongly enriched in the SED, interact with M cells, and are necessary for antigen presentation to immune effector cells. This review focuses on recent advances, which have allowed distinguishing the different PP mononuclear phagocyte subsets. It gives an overview of their diversity, specificity, location, and functions. Interaction of PP phagocytes with the microbiota and the follicle-associated epithelium as well as PP infection studies are described in the light of these new criteria of PP phagocyte identification. Finally, known alterations affecting the different phagocyte subsets during PP stimulation or infection are discussed.
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Affiliation(s)
| | - Camille Wagner
- Aix-Marseille University, CNRS, INSERM, CIML, Marseille, France
| | - Johnny Bonnardel
- Laboratory of Myeloid Cell Ontogeny and Functional Specialisation, VIB Inflammation Research Center, Ghent, Belgium
| | | | - Hugues Lelouard
- Aix-Marseille University, CNRS, INSERM, CIML, Marseille, France
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57
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Vigilance or Subversion? Constitutive and Inducible M Cells in Mucosal Tissues. Trends Immunol 2017; 39:185-195. [PMID: 28958392 DOI: 10.1016/j.it.2017.09.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 09/01/2017] [Accepted: 09/07/2017] [Indexed: 02/08/2023]
Abstract
Microfold (M) cells are epithelial cells present in mucosal tissues and specialized for the capture of luminal microparticles and their delivery to underlying immune cells; thus, they are crucial participants in mucosal immune surveillance. Multiple phenotypic subsets of M cells have now been described, all sharing a unique apical morphology that provides clues to their ability to capture microbial particles. The existence of diverse M cell phenotypes, especially inflammation-inducible M cells, provides an intriguing puzzle: some variants may augment luminal surveillance to boost mucosal immunity, while others may promote microbial access to tissues. Here, I consider the unique induction requirements of each M cell subset and functional differences, highlighting the potentially distinct consequences in mucosal immunity.
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58
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Yoo BB, Mazmanian SK. The Enteric Network: Interactions between the Immune and Nervous Systems of the Gut. Immunity 2017; 46:910-926. [PMID: 28636959 PMCID: PMC5551410 DOI: 10.1016/j.immuni.2017.05.011] [Citation(s) in RCA: 289] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 05/25/2017] [Accepted: 05/31/2017] [Indexed: 12/16/2022]
Abstract
Interactions between the nervous and immune systems enable the gut to respond to the variety of dietary products that it absorbs, the broad spectrum of pathogens that it encounters, and the diverse microbiome that it harbors. The enteric nervous system (ENS) senses and reacts to the dynamic ecosystem of the gastrointestinal (GI) tract by translating chemical cues from the environment into neuronal impulses that propagate throughout the gut and into other organs in the body, including the central nervous system (CNS). This review will describe the current understanding of the anatomy and physiology of the GI tract by focusing on the ENS and the mucosal immune system. We highlight emerging literature that the ENS is essential for important aspects of microbe-induced immune responses in the gut. Although most basic and applied research in neuroscience has focused on the brain, the proximity of the ENS to the immune system and its interface with the external environment suggest that novel paradigms for nervous system function await discovery.
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Affiliation(s)
- Bryan B Yoo
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
| | - Sarkis K Mazmanian
- Division of Biology & Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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59
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Parnell EA, Walch EM, Lo DD. Inducible Colonic M Cells Are Dependent on TNFR2 but Not Ltβr, Identifying Distinct Signalling Requirements for Constitutive Versus Inducible M Cells. J Crohns Colitis 2017; 11:751-760. [PMID: 27932454 PMCID: PMC5881705 DOI: 10.1093/ecco-jcc/jjw212] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 11/16/2016] [Indexed: 02/08/2023]
Abstract
BACKGROUND AND AIMS M cells associated with organised lymphoid tissues such as intestinal Peyer's patches provide surveillance of the intestinal lumen. Inflammation or infection in the colon can induce an M cell population associated with lymphoid infiltrates; paradoxically, induction is dependent on the inflammatory cytokine tumour necrosis factor [TNF]-α. Anti-TNFα blockade is an important therapeutic in inflammatory bowel disease, so understanding the effects of TNFα signalling is important in refining therapeutics. METHODS To dissect pro-inflammatory signals from M cell inductive signals, we used confocal microscopy image analysis to assess requirements for specific cytokine receptor signals using TNF receptor 1 [TNFR1] and 2 [TNFR2] knockouts [ko] back-crossed to the PGRP-S-dsRed transgene; separate groups were treated with soluble lymphotoxin β receptor [sLTβR] to block LTβR signalling. All groups were treated with dextran sodium sulphate [DSS] to induce colitis. RESULTS Deficiency of TNFR1 or TNFR2 did not prevent DSS-induced inflammation nor induction of stromal cell expression of receptor activator of nuclear factor kappa-B ligand [RANKL], but absence of TNFR2 prevented M cell induction. LTβR blockade had no effect on M cell induction, but it appeared to reduce RANKL induction below adjacent M cells. CONCLUSIONS TNFR2 is required for inflammation-inducible M cells, indicating that constitutive versus inflammation-inducible M cells depend on different triggers. The inducible M cell dependence on TNFR2 suggests that this specific subset is dependent on TNFα in addition to a presumed requirement for RANKL. Since inducible M cell function will influence immune responses, selective blockade of TNFα may affect colonic inflammation.
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Affiliation(s)
- Erinn A. Parnell
- Division of Biomedical Sciences, University of California Riverside School of Medicine,Riverside, CA, USA.
| | - Erin M. Walch
- Division of Biomedical Sciences, University of California Riverside School of Medicine,Riverside, CA, USA.
| | - David D. Lo
- Division of Biomedical Sciences, University of California Riverside School of Medicine,Riverside, CA, USA.
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60
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Enterohemorrhagic Escherichia coli pathogenesis: role of Long polar fimbriae in Peyer's patches interactions. Sci Rep 2017; 7:44655. [PMID: 28317910 PMCID: PMC5357955 DOI: 10.1038/srep44655] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 02/13/2017] [Indexed: 11/14/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) are major food-borne pathogens whose survival and virulence in the human digestive tract remain unclear owing to paucity of relevant models. EHEC interact with the follicle-associated epithelium of Peyer’s patches of the distal ileum and translocate across the intestinal epithelium via M-cells, but the underlying molecular mechanisms are still unknown. Here, we investigated the involvement of Long polar fimbriae (Lpf) in EHEC pathogenesis. Of the 236 strains tested, a significant association was observed between the presence of lpf operons and pathogenicity. In sophisticated in vitro models of the human gastro-intestinal tract, lpf expression was induced during transit through the simulated stomach and small intestine, but not in the colonic compartment. To investigate the involvement of Lpf in EHEC pathogenesis, lpf isogenic mutants and their relative trans-complemented strains were generated. Translocation across M-cells, interactions with murine ileal biopsies containing Peyer’s patches and the number of hemorrhagic lesions were significantly reduced with the lpf mutants compared to the wild-type strain. Complementation of lpf mutants fully restored the wild-type phenotypes. Our results indicate that (i) EHEC might colonize the terminal ileum at the early stages of infection, (ii) Lpf are an important player in the interactions with Peyer’s patches and M-cells, and could contribute to intestinal colonization.
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61
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Abstract
Nucleotide-binding oligomerization domain 2 (NOD2) is an intracellular pattern recognition receptor that senses bacterial peptidoglycan (PGN)-conserved motifs in cytosol and stimulates host immune response. The association of NOD2 mutations with a number of inflammatory pathologies, including Crohn disease (CD), Graft-versus-host disease (GVHD), and Blau syndrome, highlights its pivotal role in host–pathogen interactions and inflammatory response. Stimulation of NOD2 by its ligand (muramyl dipeptide) activates pro-inflammatory pathways such as nuclear factor-κB (NF-κB), mitogen-activated protein kinases (MAPKs), and Caspase-1. A loss of NOD2 function may result in a failure in the control of microbial infection, thereby initiating systemic responses and aberrant inflammation. Because the ligand of Nod2 is conserved in both gram-positive and gram-negative bacteria, NOD2 detects a wide variety of microorganisms. Furthermore, current literature evidences that NOD2 is also able to control viruses’ and parasites’ infections. In this review, we present and discuss recent developments about the role of NOD2 in shaping the gut commensal microbiota and pathogens, including bacteria, viruses, and parasites, and the mechanisms by which Nod2 mutations participate in disease occurrence.
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Affiliation(s)
- Ziad Al Nabhani
- Laboratoire Inflamex, Université Paris-Diderot Sorbonne Paris-Cité, Paris, France
- INSERM, UMR 1149, Paris, France
| | - Gilles Dietrich
- IRSD, Université de Toulouse, INSERM, INRA, ENVT, UPS, Toulouse, France
| | - Jean-Pierre Hugot
- Laboratoire Inflamex, Université Paris-Diderot Sorbonne Paris-Cité, Paris, France
- INSERM, UMR 1149, Paris, France
- Assistance Publique Hôpitaux de Paris, Hôpital Robert Debré, Paris, France
- * E-mail: (JPH); (FB)
| | - Frederick Barreau
- IRSD, Université de Toulouse, INSERM, INRA, ENVT, UPS, Toulouse, France
- * E-mail: (JPH); (FB)
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62
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Allograft inflammatory factor 1 is a regulator of transcytosis in M cells. Nat Commun 2017; 8:14509. [PMID: 28224999 PMCID: PMC5322540 DOI: 10.1038/ncomms14509] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 01/05/2017] [Indexed: 12/14/2022] Open
Abstract
M cells in follicle-associated epithelium (FAE) are specialized antigen-sampling cells that take up intestinal luminal antigens. Transcription factor Spi-B regulates M-cell maturation, but the molecules that promote transcytosis within M cells are not fully identified. Here we show that mouse allograft inflammatory factor 1 (Aif1) is expressed by M cells and contributes to M-cell transcytosis. FAE in Aif1−/− mice has suppressed uptake of particles and commensal bacteria, compared with wild-type mice. Translocation of Yersinia enterocolitica, but not of Salmonella enterica serovar Typhimurium, leading to the generation of antigen-specific IgA antibodies, is also diminished in Aif1-deficient mice. Although β1 integrin, which acts as a receptor for Y. enterocolitica via invasin protein, is expressed on the apical surface membranes of M cells, its active form is rarely found in Aif1−/− mice. These findings show that Aif1 is important for bacterial and particle transcytosis in M cells. M cells are intestinal epithelial cells that are specialized to transcytose antigens and bacteria from the intestinal lumen to antigen presenting cells on the other side. Here the authors show that the actin-binding protein Aif1 is highly expressed by intestinal M cells and regulates this transcytosis.
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63
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Kim SH, Jang YS. The development of mucosal vaccines for both mucosal and systemic immune induction and the roles played by adjuvants. Clin Exp Vaccine Res 2017; 6:15-21. [PMID: 28168169 PMCID: PMC5292352 DOI: 10.7774/cevr.2017.6.1.15] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/21/2016] [Accepted: 12/23/2016] [Indexed: 01/22/2023] Open
Abstract
Vaccination is the most successful immunological practice that improves the quality of human life and health. Vaccine materials include antigens of pathogens and adjuvants potentiating the effectiveness of vaccination. Vaccines are categorized using various criteria, including the vaccination material used and the method of administration. Traditionally, vaccines have been injected via needles. However, given that most pathogens first infect mucosal surfaces, there is increasing interest in the establishment of protective mucosal immunity, achieved by vaccination via mucosal routes. This review summarizes recent developments in mucosal vaccines and their associated adjuvants.
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Affiliation(s)
- Sae-Hae Kim
- Department of Molecular Biology and Institute for Molecular Biology and Genetics, Chonbuk National University, Jeonju, Korea
| | - Yong-Suk Jang
- Department of Molecular Biology and Institute for Molecular Biology and Genetics, Chonbuk National University, Jeonju, Korea.; Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Chonbuk National University, Jeonju, Korea
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64
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Kurashima Y, Kiyono H. Mucosal Ecological Network of Epithelium and Immune Cells for Gut Homeostasis and Tissue Healing. Annu Rev Immunol 2017; 35:119-147. [PMID: 28125357 DOI: 10.1146/annurev-immunol-051116-052424] [Citation(s) in RCA: 184] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The intestinal epithelial barrier includes columnar epithelial, Paneth, goblet, enteroendocrine, and tuft cells as well as other cell populations, all of which contribute properties essential for gastrointestinal homeostasis. The intestinal mucosa is covered by mucin, which contains antimicrobial peptides and secretory IgA and prevents luminal bacteria, fungi, and viruses from stimulating intestinal immune responses. Conversely, the transport of luminal microorganisms-mediated by M, dendritic, and goblet cells-into intestinal tissues facilitates the harmonization of active and quiescent mucosal immune responses. The bacterial population within gut-associated lymphoid tissues creates the intratissue cohabitations for harmonized mucosal immunity. Intermolecular and intercellular communication among epithelial, immune, and mesenchymal cells creates an environment conducive for epithelial regeneration and mucosal healing. This review summarizes the so-called intestinal mucosal ecological network-the complex but vital molecular and cellular interactions of epithelial mesenchymal cells, immune cells, and commensal microbiota that achieve intestinal homeostasis, regeneration, and healing.
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Affiliation(s)
- Yosuke Kurashima
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan; .,International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan.,Institute for Global Prominent Research, Chiba University, Chiba 260-8670, Japan.,Department of Mucosal Immunology, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan.,Department of Innovative Medicine, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan.,Chiba University-UC San Diego Center for Mucosal Immunology, Allergy, and Vaccine, La Jolla, CA 92093
| | - Hiroshi Kiyono
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan; .,International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan.,Chiba University-UC San Diego Center for Mucosal Immunology, Allergy, and Vaccine, La Jolla, CA 92093.,Department of Immunology, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
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65
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Manipulation of host membranes by the bacterial pathogens Listeria, Francisella, Shigella and Yersinia. Semin Cell Dev Biol 2016; 60:155-167. [PMID: 27448494 PMCID: PMC7082150 DOI: 10.1016/j.semcdb.2016.07.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 07/15/2016] [Accepted: 07/18/2016] [Indexed: 01/07/2023]
Abstract
Bacterial pathogens display an impressive arsenal of molecular mechanisms that allow survival in diverse host niches. Subversion of plasma membrane and cytoskeletal functions are common themes associated to infection by both extracellular and intracellular pathogens. Moreover, intracellular pathogens modify the structure/stability of their membrane-bound compartments and escape degradation from phagocytic or autophagic pathways. Here, we review the manipulation of host membranes by Listeria monocytogenes, Francisella tularensis, Shigella flexneri and Yersinia spp. These four bacterial model pathogens exemplify generalized strategies as well as specific features observed during bacterial infection processes.
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66
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Abstract
The human pathogens
Yersinia pseudotuberculosis and
Yersinia enterocolitica cause enterocolitis, while
Yersinia pestis is responsible for pneumonic, bubonic, and septicaemic plague. All three share an infection strategy that relies on a virulence factor arsenal to enable them to enter, adhere to, and colonise the host while evading host defences to avoid untimely clearance. Their arsenal includes a number of adhesins that allow the invading pathogens to establish a foothold in the host and to adhere to specific tissues later during infection. When the host innate immune system has been activated, all three pathogens produce a structure analogous to a hypodermic needle. In conjunction with the translocon, which forms a pore in the host membrane, the channel that is formed enables the transfer of six ‘effector’ proteins into the host cell cytoplasm. These proteins mimic host cell proteins but are more efficient than their native counterparts at modifying the host cell cytoskeleton, triggering the host cell suicide response. Such a sophisticated arsenal ensures that yersiniae maintain the upper hand despite the best efforts of the host to counteract the infecting pathogen.
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Affiliation(s)
- Steve Atkinson
- Centre for Biomolecular Sciences, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Paul Williams
- Centre for Biomolecular Sciences, School of Life Sciences, University of Nottingham, Nottingham, UK
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67
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Chauhan N, Wrobel A, Skurnik M, Leo JC. Yersinia adhesins: An arsenal for infection. Proteomics Clin Appl 2016; 10:949-963. [PMID: 27068449 DOI: 10.1002/prca.201600012] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/14/2016] [Accepted: 04/06/2016] [Indexed: 11/09/2022]
Abstract
The Yersiniae are a group of Gram-negative coccobacilli inhabiting a wide range of habitats. The genus harbors three recognized human pathogens: Y. enterocolitica and Y. pseudotuberculosis, which both cause gastrointestinal disease, and Y. pestis, the causative agent of plague. These three organisms have served as models for a number of aspects of infection biology, including adhesion, immune evasion, evolution of pathogenic traits, and retracing the course of ancient pandemics. The virulence of the pathogenic Yersiniae is heavily dependent on a number of adhesin molecules. Some of these, such as the Yersinia adhesin A and invasin of the enteropathogenic species, and the pH 6 antigen of Y. pestis, have been extensively studied. However, genomic sequencing has uncovered a host of other adhesins present in these organisms, the functions of which are only starting to be investigated. Here, we review the current state of knowledge on the adhesin molecules present in the Yersiniae, and their functions and putative roles in the infection process.
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Affiliation(s)
- Nandini Chauhan
- Evolution and Genetics, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Agnieszka Wrobel
- Evolution and Genetics, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Mikael Skurnik
- Department of Bacteriology and Immunology, Medicum, Research Programs Unit, Immunobiology, University of Helsinki, Helsinki, Finland.,Central Hospital Laboratory Diagnostics, Helsinki University, Helsinki, Finland
| | - Jack C Leo
- Evolution and Genetics, Department of Biosciences, University of Oslo, Oslo, Norway.
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68
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Mononuclear phagocytes contribute to intestinal invasion and dissemination of Yersinia enterocolitica. Int J Med Microbiol 2016; 306:357-66. [PMID: 27107739 DOI: 10.1016/j.ijmm.2016.04.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 04/05/2016] [Accepted: 04/14/2016] [Indexed: 12/30/2022] Open
Abstract
Enteropathogenic Yersinia enterocolitica (Ye) enters the host via contaminated food. After colonisation of the small intestine Ye invades the Peyer's patches (PPs) via M cells and disseminates to the mesenteric lymph nodes (MLNs), spleen and liver. Whether Ye uses other invasion routes and which pathogenicity factors are required remains elusive. Oral infection of lymphotoxin-β-receptor deficient mice lacking PPs and MLNs with Ye revealed similar bacterial load in the spleen 1h post infection as wild-type mice, demonstrating a PP-independent dissemination route for Ye. Immunohistological analysis of the small intestine revealed Ye in close contact with mononuclear phagocytes (MPs), specifically CX3CR1(+) monocyte-derived cells (MCs) as well as CD103(+) dendritic cells (DCs). This finding was confirmed by flow cytometry and imaging flow cytometry analysis of lamina propria (LP) leukocytes showing CD103(+) DCs and MCs with intracellular Ye. Uptake of Ye by LP CD103(+) DCs and MCs was dependent on the pathogenicity factor invasin, whereas the adhesin YadA was dispensable as demonstrated by Ye deletion mutants. Furthermore, Ye were found exclusively associated with CD103(+) DCs in the MLNs from wild-type mice, but not from CCR7(-/-) mice, demonstrating a CCR7 dependent transport of Ye by CD103(+) DCs from LP to the MLNs. In contrast, dissemination of Ye to the spleen was dependent on MCs as significantly less Ye could be recovered from the spleen of CX3CR1(GFP/GFP) mice compared to wild-type mice. Altogether, MCs and CD103(+) DCs contribute to immediate invasion and dissemination of Ye. This together with data from other bacteria suggests MPs as general pathogenic entry site in the intestine.
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69
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Khan TA, Wang X, Maynard JA. Inclusion of an RGD Motif Alters Invasin Integrin-Binding Affinity and Specificity. Biochemistry 2016; 55:2078-90. [DOI: 10.1021/acs.biochem.5b01243] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tarik A. Khan
- Departments of Chemical Engineering and ‡Biochemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Xianzhe Wang
- Departments of Chemical Engineering and ‡Biochemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Jennifer A. Maynard
- Departments of Chemical Engineering and ‡Biochemistry, University of Texas at Austin, Austin, Texas 78712, United States
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Bennett KM, Parnell EA, Sanscartier C, Parks S, Chen G, Nair MG, Lo DD. Induction of Colonic M Cells during Intestinal Inflammation. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:1166-79. [PMID: 26948422 DOI: 10.1016/j.ajpath.2015.12.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 11/24/2015] [Accepted: 12/21/2015] [Indexed: 02/06/2023]
Abstract
Intestinal M (microfold) cells are specialized epithelial cells overlying lymphoid tissues in the small intestine. Unlike common enterocytes, M cells lack an organized apical brush border, and are able to transcytose microparticles across the mucosal barrier to underlying antigen-presenting cells. We found that in both the dextran sodium sulfate and Citrobacter rodentium models of colitis, significantly increased numbers of Peyer's patch (PP) phenotype M cells were induced at the peak of inflammation in colonic epithelium, often accompanied by loosely organized lamina propria infiltrates. PP type M cells are thought to be dependent on cytokines, including tumor necrosis factor (TNF)-α and receptor activator of nuclear factor kappa-B ligand; these cytokines were also found to be induced in the inflamed tissues. The induction of M cells was abrogated by anti-TNF-α blockade, suggesting that anti-TNF-α therapies may have similar effects in clinical settings, although the functional consequences are not clear. Our results suggest that inflammatory cytokine-induced PP type M cells may be a useful correlate of chronic intestinal inflammation.
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Affiliation(s)
- Kaila M Bennett
- Bioengineering Interdepartmental Graduate Program, School of Medicine, University of California, Riverside, Riverside, California; Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California
| | - Erinn A Parnell
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California
| | - Candice Sanscartier
- Bioengineering Interdepartmental Graduate Program, School of Medicine, University of California, Riverside, Riverside, California; Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California
| | - Sophia Parks
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California
| | - Gang Chen
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California
| | - Meera G Nair
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California
| | - David D Lo
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California.
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71
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Zeng MY, Cisalpino D, Varadarajan S, Hellman J, Warren HS, Cascalho M, Inohara N, Núñez G. Gut Microbiota-Induced Immunoglobulin G Controls Systemic Infection by Symbiotic Bacteria and Pathogens. Immunity 2016; 44:647-658. [PMID: 26944199 DOI: 10.1016/j.immuni.2016.02.006] [Citation(s) in RCA: 272] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 11/10/2015] [Accepted: 12/07/2015] [Indexed: 12/21/2022]
Abstract
The gut microbiota is compartmentalized in the intestinal lumen and induces local immune responses, but it remains unknown whether the gut microbiota can induce systemic response and contribute to systemic immunity. We report that selective gut symbiotic gram-negative bacteria were able to disseminate systemically to induce immunoglobulin G (IgG) response, which primarily targeted gram-negative bacterial antigens and conferred protection against systemic infections by E. coli and Salmonella by directly coating bacteria to promote killing by phagocytes. T cells and Toll-like receptor 4 on B cells were important in the generation of microbiota-specific IgG. We identified murein lipoprotein (MLP), a highly conserved gram-negative outer membrane protein, as a major antigen that induced systemic IgG homeostatically in both mice and humans. Administration of anti-MLP IgG conferred crucial protection against systemic Salmonella infection. Thus, our findings reveal an important function for the gut microbiota in combating systemic infection through the induction of protective IgG.
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Affiliation(s)
- Melody Y Zeng
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Daniel Cisalpino
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109, USA; Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG 31270-901, Brazil
| | - Saranyaraajan Varadarajan
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Judith Hellman
- Department of Anesthesia and Perioperative Care, Division of Critical Care Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - H Shaw Warren
- Infectious Disease Unit, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Marilia Cascalho
- Transplantation Biology, Department of Surgery and Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Naohiro Inohara
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Gabriel Núñez
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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Hondo T, Someya S, Nagasawa Y, Terada S, Watanabe H, Chen X, Watanabe K, Ohwada S, Kitazawa H, Rose MT, Nochi T, Aso H. Cyclophilin A is a new M cell marker of bovine intestinal epithelium. Cell Tissue Res 2016; 364:585-597. [DOI: 10.1007/s00441-015-2342-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 12/03/2015] [Indexed: 12/20/2022]
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73
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Boyle EC, Dombrowsky H, Sarau J, Braun J, Aepfelbacher M, Lautenschläger I, Grassl GA. Ex vivo perfusion of the isolated rat small intestine as a novel model of Salmonella enteritis. Am J Physiol Gastrointest Liver Physiol 2016; 310:G55-63. [PMID: 26564721 DOI: 10.1152/ajpgi.00444.2014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 11/11/2015] [Indexed: 01/31/2023]
Abstract
Using an ex vivo perfused rat small intestinal model, we examined pathological changes to the tissue, inflammation induction, as well as dynamic changes to smooth muscle activity, metabolic competence, and luminal fluid accumulation during short-term infection with the enteropathogenic bacteria Salmonella enterica serovar Typhimurium and Yersinia enterocolitica. Although few effects were seen upon Yersinia infection, this system accurately modeled key aspects associated with Salmonella enteritis. Our results confirmed the importance of the Salmonella Pathogenicity Island 1 (SPI1)-encoded type 3 secretion system (T3SS) in pathology, tissue invasion, inflammation induction, and fluid secretion. Novel physiological consequences of Salmonella infection of the small intestine were also identified, namely, SPI-1-dependent vasoconstriction and SPI-1-independent reduction in the digestive and absorptive functions of the epithelium. Importantly, this is the first small animal model that allows for the study of Salmonella-induced fluid secretion. Another major advantage of this model is that one can specifically determine the contribution of resident cell populations. Accordingly, we can conclude that recruited cell populations were not involved in the pathological damage, inflammation induction, fluid accumulation, nutrient absorption deficiency, and vasoconstriction observed. Although fluid loss induced by Salmonella infection is hypothesized to be due to damage caused by recruited neutrophils, our data suggest that bacterial invasion and inflammation induction in resident cell populations are sufficient for fluid loss into the lumen. In summary, this model is a novel and useful tool that allows for detailed examination of the early physiopathological effects of Salmonella infection on the small intestine.
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Affiliation(s)
- Erin C Boyle
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Bernhard Nocht Institute of Tropical Medicine, Hamburg, Germany
| | - Heike Dombrowsky
- Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany
| | - Jürgen Sarau
- Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany
| | - Janin Braun
- Priority Area Infections, Models of Inflammation, Research Center Borstel, Borstel, Germany; Institute for Experimental Medicine, Christian-Albrechts University Kiel, Kiel, Germany
| | - Martin Aepfelbacher
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ingmar Lautenschläger
- Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany; Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Kiel, Germany; and
| | - Guntram A Grassl
- Priority Area Infections, Models of Inflammation, Research Center Borstel, Borstel, Germany; Institute for Experimental Medicine, Christian-Albrechts University Kiel, Kiel, Germany; Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School and German Center for Infection Research (DZIF), Hannover, Germany
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74
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Zeitouni NE, Dersch P, Naim HY, von Köckritz-Blickwede M. Hypoxia Decreases Invasin-Mediated Yersinia enterocolitica Internalization into Caco-2 Cells. PLoS One 2016; 11:e0146103. [PMID: 26731748 PMCID: PMC4701670 DOI: 10.1371/journal.pone.0146103] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 12/14/2015] [Indexed: 12/20/2022] Open
Abstract
Yersinia enterocolitica is a major cause of human yersiniosis, with enterocolitis being a typical manifestation. These bacteria can cross the intestinal mucosa, and invade eukaryotic cells by binding to host β1 integrins, a process mediated by the bacterial effector protein invasin. This study examines the role of hypoxia on the internalization of Y. enterocolitica into intestinal epithelial cells, since the gastrointestinal tract has been shown to be physiologically deficient in oxygen levels (hypoxic), especially in cases of infection and inflammation. We show that hypoxic pre-incubation of Caco-2 cells resulted in significantly decreased bacterial internalization compared to cells grown under normoxia. This phenotype was absent after functionally blocking host β1 integrins as well as upon infection with an invasin-deficient Y. enterocolitica strain. Furthermore, downstream phosphorylation of the focal adhesion kinase was also reduced under hypoxia after infection. In good correlation to these data, cells grown under hypoxia showed decreased protein levels of β1 integrins at the apical cell surface whereas the total protein level of the hypoxia inducible factor (HIF-1) alpha was elevated. Furthermore, treatment of cells with the HIF-1 α stabilizer dimethyloxalylglycine (DMOG) also reduced invasion and decreased β1 integrin protein levels compared to control cells, indicating a potential role for HIF-1α in this process. These results suggest that hypoxia decreases invasin-integrin-mediated internalization of Y. enterocolitica into intestinal epithelial cells by reducing cell surface localization of host β1 integrins.
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Affiliation(s)
- Nathalie E. Zeitouni
- Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Petra Dersch
- Helmholtz Center for Infection Research, Braunschweig, Germany
| | - Hassan Y. Naim
- Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Maren von Köckritz-Blickwede
- Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Hannover, Germany
- * E-mail:
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75
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Li H, Ning P, Lin Z, Liang W, Kang K, He L, Zhang Y. Co-expression of the C-terminal domain of Yersinia enterocolitica invasin enhances the efficacy of classical swine-fever-vectored vaccine based on human adenovirus. J Biosci 2015; 40:79-90. [PMID: 25740144 DOI: 10.1007/s12038-014-9495-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The use of adenovirus vector-based vaccines is a promising approach for generating antigen-specific immune responses. Improving vaccine potency is necessary in other approaches to address their inadequate protection for the majority of infectious diseases. This study is the first to reconstruct a recombinant replication-defective human adenovirus co-expressing E2 and invasin C-terminal (InvC) glycoproteins (rAd-E2-InvC). rAd-E2-InvC with 2 x 10(6) TCID50 was intramuscularly administered two times to CSFV-free pigs at 14 day intervals. No adverse clinical reactions were observed in any of the pigs after the vaccination. The CSFV E2-specific antibody titer was significantly higher in the rAd-E2-InvC group than that in the rAdV-E2 group as measured by NPLA and blocking ELISA. Pigs immunized with rAd-E2-InvC were completely protected against lethal challenge. Neither CSFV RNA nor pathological changes were detected in the tissues after CSFV challenge. These results demonstrate that rAd-E2-InvC could be an alternative to the existing CSF vaccine. Moreover, InvC that acts as an adjuvant could enhance the immunogenicity of rAdV-E2 and induce high CSFV E2-specific antibody titer and protection level.
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Affiliation(s)
- Helin Li
- College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi, China
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76
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Ohno H. Intestinal M cells. J Biochem 2015; 159:151-60. [PMID: 26634447 DOI: 10.1093/jb/mvv121] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 11/27/2015] [Indexed: 11/13/2022] Open
Abstract
We have an enormous number of commensal bacteria in our intestine, moreover, the foods that we ingest and the water we drink is sometimes contaminated with pathogenic microorganisms. The intestinal epithelium is always exposed to such microbes, friend or foe, so to contain them our gut is equipped with specialized gut-associated lymphoid tissue (GALT), literally the largest peripheral lymphoid tissue in the body. GALT is the intestinal immune inductive site composed of lymphoid follicles such as Peyer's patches. M cells are a subset of intestinal epithelial cells (IECs) residing in the region of the epithelium covering GALT lymphoid follicles. Although the vast majority of IEC function to absorb nutrients from the intestine, M cells are highly specialized to take up intestinal microbial antigens and deliver them to GALT for efficient mucosal as well as systemic immune responses. I will discuss recent advances in our understanding of the molecular mechanisms of M-cell differentiation and functions.
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Affiliation(s)
- Hiroshi Ohno
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
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77
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Wang M, Gao Z, Zhang Z, Pan L, Zhang Y. Roles of M cells in infection and mucosal vaccines. Hum Vaccin Immunother 2015; 10:3544-51. [PMID: 25483705 DOI: 10.4161/hv.36174] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The mucosal immune system plays a crucial part in the control of infection. Exposure of humans and animals to potential pathogens generally occurs through mucosal surfaces, thus, strategies that target the mucosa seem rational and efficient vaccination measures. Vaccination through the mucosal immune system can induce effective systemic immune responses simultaneously with mucosal immunity compared with parenteral vaccination. M cells are capable of transporting luminal antigens to the underlying lymphoid tissues and can be exploited by pathogens as an entry portal to invade the host. Therefore, targeting M-cell-specific molecules might enhance antigen entry, initiate the immune response, and induce protection against mucosal pathogens. Here, we outline our understanding of the distribution and function of M cells, and summarize the advances in mucosal vaccine strategies that target M cells.
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Key Words
- ANX, Annexin; BALT, bronchus-associated lymphoid tissue
- C5aR, C5a receptor
- DCs, dendritic cells
- DENV, dengue virus
- EDIII, envelope domain III
- FAE, follicle-associated epithelium
- GALT, gut-associated lymphoid tissue
- GENALT, genital-associated lymphoid tissue
- GP2, Glycoprotein 2
- Hsp60, heat shock protein 60
- LPS, lipopolysaccharide
- M cells
- M cells, microfold cells
- MALT, mucosa-associated lymphoid tissue
- NALT, nasopharynx- or nose-associated lymphoid tissue
- OVA, ovalbumin
- OmpH, outer membrane protein H
- PP, Peyer's patches
- PRRs, pathogen recognition receptors
- PrPC, cellular prion protein
- SELEX, Systematic Evolution of Ligands by EXponential enrichment
- SIgA secretory IgA
- TLR-4, Toll-like receptor-4
- UEA-1,Ulex europaeus agglutinin-1
- antigen
- infection
- mucosal immunity
- pσ1, reovirus surface protein σ1
- vaccine
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Affiliation(s)
- Miao Wang
- a State Key Laboratory of Veterinary Etiological Biology; National Foot-and-Mouse Disease Reference Laboratory; Lanzhou Veterinary Research Institute; CAAS ; Lanzhou , Gansu , China
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78
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Albac S, Schmitz A, Lopez-Alayon C, d'Enfert C, Sautour M, Ducreux A, Labruère-Chazal C, Laue M, Holland G, Bonnin A, Dalle F. Candida albicansis able to use M cells as a portal of entry across the intestinal barrierin vitro. Cell Microbiol 2015; 18:195-210. [DOI: 10.1111/cmi.12495] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Accepted: 07/21/2015] [Indexed: 01/18/2023]
Affiliation(s)
- Sandrine Albac
- UMR 1347, Université de Bourgogne Franche-Comté; 17 Rue Sully, BP 86 510 F-21065 Dijon Cedex France
| | - Antonin Schmitz
- UMR 1347, Université de Bourgogne Franche-Comté; 17 Rue Sully, BP 86 510 F-21065 Dijon Cedex France
| | - Carolina Lopez-Alayon
- UMR 1347, Université de Bourgogne Franche-Comté; 17 Rue Sully, BP 86 510 F-21065 Dijon Cedex France
| | - Christophe d'Enfert
- Institut Pasteur; Unité Biologie et Pathogénicité Fongiques, Département Mycologie; Paris France
- INRA; USC 2019; Paris France
| | - Marc Sautour
- UMR 1347, Université de Bourgogne Franche-Comté; 17 Rue Sully, BP 86 510 F-21065 Dijon Cedex France
- Centre Hospitalier Universitaire; Service de Parasitologie Mycologie; 2 Rue Angélique Ducoudray F-21070 Dijon Cedex France
| | - Amandine Ducreux
- UMR 1347, Université de Bourgogne Franche-Comté; 17 Rue Sully, BP 86 510 F-21065 Dijon Cedex France
| | - Catherine Labruère-Chazal
- Université de Bourgogne Franche-Comté; Institut de Mathématiques de Bourgogne, UFR Sciences et Techniques; Dijon France
| | - Michael Laue
- Robert Koch-Institute; Centre for Biological Threats and Special Pathogens, Advanced Light and Electron Microscopy; Nordufer 20 13353 Berlin Germany
| | - Gudrun Holland
- Robert Koch-Institute; Centre for Biological Threats and Special Pathogens, Advanced Light and Electron Microscopy; Nordufer 20 13353 Berlin Germany
| | - Alain Bonnin
- UMR 1347, Université de Bourgogne Franche-Comté; 17 Rue Sully, BP 86 510 F-21065 Dijon Cedex France
- Centre Hospitalier Universitaire; Service de Parasitologie Mycologie; 2 Rue Angélique Ducoudray F-21070 Dijon Cedex France
| | - Frederic Dalle
- UMR 1347, Université de Bourgogne Franche-Comté; 17 Rue Sully, BP 86 510 F-21065 Dijon Cedex France
- Centre Hospitalier Universitaire; Service de Parasitologie Mycologie; 2 Rue Angélique Ducoudray F-21070 Dijon Cedex France
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79
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Araújo F, Pereira C, Costa J, Barrias C, Granja PL, Sarmento B. In vitroM-like cells genesis through a tissue-engineered triple-culture intestinal model. J Biomed Mater Res B Appl Biomater 2015; 104:782-8. [DOI: 10.1002/jbm.b.33508] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Revised: 07/18/2015] [Accepted: 08/14/2015] [Indexed: 01/22/2023]
Affiliation(s)
- Francisca Araújo
- I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto; Portugal
- INEB-Instituto de Engenharia Biomédica, University of Porto; Rua do Campo Alegre, 823 Porto 4150-180 Portugal
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, University of Porto; Rua de Jorge Viterbo Ferreira Porto 4050-313 Portugal
| | - Carla Pereira
- I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto; Portugal
- INEB-Instituto de Engenharia Biomédica, University of Porto; Rua do Campo Alegre, 823 Porto 4150-180 Portugal
- FEUP-Faculdade de Engenharia, University of Porto; Rua Dr. Roberto Frias Porto 4200-465 Portugal
| | - Joana Costa
- I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto; Portugal
- INEB-Instituto de Engenharia Biomédica, University of Porto; Rua do Campo Alegre, 823 Porto 4150-180 Portugal
- FEUP-Faculdade de Engenharia, University of Porto; Rua Dr. Roberto Frias Porto 4200-465 Portugal
| | - Cristina Barrias
- I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto; Portugal
- INEB-Instituto de Engenharia Biomédica, University of Porto; Rua do Campo Alegre, 823 Porto 4150-180 Portugal
| | - Pedro L. Granja
- I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto; Portugal
- INEB-Instituto de Engenharia Biomédica, University of Porto; Rua do Campo Alegre, 823 Porto 4150-180 Portugal
- ICBAS-Instituto de Ciências Biomédicas Abel Salazar, University of Porto; Rua de Jorge Viterbo Ferreira Porto 4050-313 Portugal
- FEUP-Faculdade de Engenharia, University of Porto; Rua Dr. Roberto Frias Porto 4200-465 Portugal
| | - Bruno Sarmento
- I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto; Portugal
- INEB-Instituto de Engenharia Biomédica, University of Porto; Rua do Campo Alegre, 823 Porto 4150-180 Portugal
- CESPU-Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Instituto Universitário de Ciências da Saúde; Rua Central de Grandra, 1317 Gandra 4585-116 Portugal
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80
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Rosenheinrich M, Heine W, Schmühl CM, Pisano F, Dersch P. Natural Killer Cells Mediate Protection against Yersinia pseudotuberculosis in the Mesenteric Lymph Nodes. PLoS One 2015; 10:e0136290. [PMID: 26296209 PMCID: PMC4546584 DOI: 10.1371/journal.pone.0136290] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 08/02/2015] [Indexed: 01/11/2023] Open
Abstract
Natural killer cells play a crucial role in the initial defense against bacterial pathogens. The crosstalk between host cells infected with intracellular pathogens and NK cells has been studied intensively, but not much attention has been given to characterize the role of NK cells in the response to extracellular bacterial pathogens such as yersiniae. In this study we used antibody-mediated NK cell depletion to address the importance of this immune cell type in controlling a Y. pseudotuberculosis infection. Analysis of the bacterial counts was used to follow the infection and flow cytometry was performed to characterize the composition and dynamic of immune cells. Depletion of NK cells led to higher bacterial loads within the mesenteric lymph nodes. We further show that in particular CD11b+ CD27+ NK cells which express higher levels of the activation marker CD69 increase within the mesenteric lymph nodes during a Y. pseudotuberculosis infection. Moreover, in response to the activation NK cells secrete higher levels of IFNy, which in turn triggers the production of the proinflammatory cytokine TNFα. These results suggest, that NK cells aid in the clearance of Y. pseudotuberculosis infections mainly by triggering the expression of proinflammatory cytokines manipulating the host immune response.
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MESH Headings
- Animals
- Antibodies/pharmacology
- Antigens, CD/genetics
- Antigens, CD/immunology
- B-Lymphocytes/immunology
- B-Lymphocytes/microbiology
- B-Lymphocytes/pathology
- Female
- Gene Expression
- Immunophenotyping
- Interferon-gamma/genetics
- Interferon-gamma/immunology
- Interferon-gamma/metabolism
- Killer Cells, Natural/drug effects
- Killer Cells, Natural/immunology
- Killer Cells, Natural/microbiology
- Killer Cells, Natural/pathology
- Lymph Nodes/immunology
- Lymph Nodes/microbiology
- Lymph Nodes/pathology
- Lymphocyte Count
- Lymphocyte Depletion
- Macrophages/immunology
- Macrophages/microbiology
- Macrophages/pathology
- Mesentery/immunology
- Mesentery/microbiology
- Mesentery/pathology
- Mice
- Mice, Inbred C57BL
- Neutrophils/immunology
- Neutrophils/microbiology
- Neutrophils/pathology
- Spleen/immunology
- Spleen/microbiology
- Spleen/pathology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/microbiology
- T-Lymphocytes, Cytotoxic/pathology
- Tumor Necrosis Factor-alpha/genetics
- Tumor Necrosis Factor-alpha/immunology
- Tumor Necrosis Factor-alpha/metabolism
- Yersinia pseudotuberculosis/immunology
- Yersinia pseudotuberculosis Infections/immunology
- Yersinia pseudotuberculosis Infections/microbiology
- Yersinia pseudotuberculosis Infections/pathology
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Affiliation(s)
- Maik Rosenheinrich
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Wiebke Heine
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Carina M. Schmühl
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Fabio Pisano
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Petra Dersch
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
- * E-mail:
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81
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Nakamura SI, Hayashidani H, Yonezawa A, Suzuki I, Une Y. Yersiniosis due to infection by Yersinia pseudotuberculosis 4b in captive meerkats (Suricata suricatta) in Japan. J Vet Diagn Invest 2015; 27:641-4. [DOI: 10.1177/1040638715596035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Two meerkats ( Suricata suricatta) housed in the same zoological garden in Japan died due to Yersinia pseudotuberculosis serotype 4b infection. Gross and microscopic lesions included necrotizing enteritis and enlargement of the spleen and liver with multifocal necrosis. Inflammatory cells, primarily neutrophils, and nuclear debris were associated with clusters of Gram-negative bacilli. Additionally, there were aberrant organism forms that were larger than bacilli and appeared as basophilic globular bodies. Immunohistochemical examination showed that the bacilli and globular bodies were strongly positive for Y. pseudotuberculosis O4 antigen. The globular bodies were considered a shape-changed form of Y. pseudotuberculosis, and these morphologically abnormal bacteria could present a diagnostic challenge.
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Affiliation(s)
- Shin-ichi Nakamura
- Laboratory of Veterinary Pathology, School of Veterinary Medicine, Azabu University, Chuo-ku, Sagamihara, Kanagawa, Japan (Nakamura, Une)
- Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan (Hayashidani)
- Himeji Central Park, Himeji, Hyogo, Japan (Yonezawa, Suzuki)
| | - Hideki Hayashidani
- Laboratory of Veterinary Pathology, School of Veterinary Medicine, Azabu University, Chuo-ku, Sagamihara, Kanagawa, Japan (Nakamura, Une)
- Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan (Hayashidani)
- Himeji Central Park, Himeji, Hyogo, Japan (Yonezawa, Suzuki)
| | - Aya Yonezawa
- Laboratory of Veterinary Pathology, School of Veterinary Medicine, Azabu University, Chuo-ku, Sagamihara, Kanagawa, Japan (Nakamura, Une)
- Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan (Hayashidani)
- Himeji Central Park, Himeji, Hyogo, Japan (Yonezawa, Suzuki)
| | - Isao Suzuki
- Laboratory of Veterinary Pathology, School of Veterinary Medicine, Azabu University, Chuo-ku, Sagamihara, Kanagawa, Japan (Nakamura, Une)
- Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan (Hayashidani)
- Himeji Central Park, Himeji, Hyogo, Japan (Yonezawa, Suzuki)
| | - Yumi Une
- Laboratory of Veterinary Pathology, School of Veterinary Medicine, Azabu University, Chuo-ku, Sagamihara, Kanagawa, Japan (Nakamura, Une)
- Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan (Hayashidani)
- Himeji Central Park, Himeji, Hyogo, Japan (Yonezawa, Suzuki)
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82
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Suzuki H, Watari A, Hashimoto E, Yonemitsu M, Kiyono H, Yagi K, Kondoh M, Kunisawa J. C-Terminal Clostridium perfringens Enterotoxin-Mediated Antigen Delivery for Nasal Pneumococcal Vaccine. PLoS One 2015; 10:e0126352. [PMID: 26018248 PMCID: PMC4446347 DOI: 10.1371/journal.pone.0126352] [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: 10/29/2014] [Accepted: 04/01/2015] [Indexed: 01/19/2023] Open
Abstract
Efficient vaccine delivery to mucosal tissues including mucosa-associated lymphoid tissues is essential for the development of mucosal vaccine. We previously reported that claudin-4 was highly expressed on the epithelium of nasopharynx-associated lymphoid tissue (NALT) and thus claudin-4-targeting using C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE) effectively delivered fused antigen to NALT and consequently induced antigen-specific immune responses. In this study, we applied the C-CPE-based vaccine delivery system to develop a nasal pneumococcal vaccine. We fused C-CPE with pneumococcal surface protein A (PspA), an important antigen for the induction of protective immunity against Streptococcus pneumoniae infection, (PspA-C-CPE). PspA-C-CPE binds to claudin-4 and thus efficiently attaches to NALT epithelium, including antigen-sampling M cells. Nasal immunization with PspA-C-CPE induced PspA-specific IgG in the serum and bronchoalveolar lavage fluid (BALF) as well as IgA in the nasal wash and BALF. These immune responses were sufficient to protect against pneumococcal infection. These results suggest that C-CPE is an efficient vaccine delivery system for the development of nasal vaccines against pneumococcal infection.
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Affiliation(s)
- Hidehiko Suzuki
- Laboratory of Vaccine Materials, National Institute of Biomedical Innovation, Health and Nutrition, Osaka 567–0085, Japan
- Laboratory of Bio-Functional Molecular Chemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565–0871, Japan
| | - Akihiro Watari
- Laboratory of Bio-Functional Molecular Chemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565–0871, Japan
| | - Eri Hashimoto
- Laboratory of Vaccine Materials, National Institute of Biomedical Innovation, Health and Nutrition, Osaka 567–0085, Japan
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Sciences, The University of Tokyo, Tokyo 108–8639, Japan
| | - Miki Yonemitsu
- Laboratory of Vaccine Materials, National Institute of Biomedical Innovation, Health and Nutrition, Osaka 567–0085, Japan
| | - Hiroshi Kiyono
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Sciences, The University of Tokyo, Tokyo 108–8639, Japan
- International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo 108–8639, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
| | - Kiyohito Yagi
- Laboratory of Bio-Functional Molecular Chemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565–0871, Japan
| | - Masuo Kondoh
- Laboratory of Bio-Functional Molecular Chemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565–0871, Japan
- * E-mail: (JK); (MK)
| | - Jun Kunisawa
- Laboratory of Vaccine Materials, National Institute of Biomedical Innovation, Health and Nutrition, Osaka 567–0085, Japan
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Sciences, The University of Tokyo, Tokyo 108–8639, Japan
- International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo 108–8639, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
- Department of Microbiology and Infectious Diseases, Kobe University Graduate School of Medicine, Kobe 650–0017, Japan
- Graduate School of Medicine, Graduate School of Pharmaceutical Sciences, and Graduate School of Dentistry, Osaka University, Osaka 565–0871, Japan
- * E-mail: (JK); (MK)
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83
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Lee TJ, Wong J, Bae S, Lee AJ, Lopatkin A, Yuan F, You L. A power-law dependence of bacterial invasion on mammalian host receptors. PLoS Comput Biol 2015; 11:e1004203. [PMID: 25879937 PMCID: PMC4399907 DOI: 10.1371/journal.pcbi.1004203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 02/19/2015] [Indexed: 01/04/2023] Open
Abstract
Pathogenic bacteria such as Listeria and Yersinia gain initial entry by binding to host target cells and stimulating their internalization. Bacterial uptake entails successive, increasingly strong associations between receptors on the surface of bacteria and hosts. Even with genetically identical cells grown in the same environment, there are vast differences in the number of bacteria entering any given cell. To gain insight into this variability, we examined uptake dynamics of Escherichia coli engineered to express the invasin surface receptor from Yersinia, which enables uptake via mammalian host β1-integrins. Surprisingly, we found that the uptake probability of a single bacterium follows a simple power-law dependence on the concentration of integrins. Furthermore, the value of a power-law parameter depends on the particular host-bacterium pair but not on bacterial concentration. This power-law captures the complex, variable processes underlying bacterial invasion while also enabling differentiation of cell lines. Uptake of bacteria by mammalian cells is highly variable within a population of host cells and between host cell types. A detailed but unwieldy mechanistic model describing individual host-pathogen receptor binding events is captured by a simple power-law dependence on the concentration of the host receptors. The power-law parameters capture characteristics of the host-bacterium pair interaction and can differentiate host cell lines. This study has important implications for understanding the accuracy and precision of therapeutics employing receptor-mediated transport of materials to mammalian hosts.
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Affiliation(s)
- Tae J. Lee
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
- Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, United States of America
| | - Jeffrey Wong
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
- Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, United States of America
| | - Sena Bae
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
- Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, United States of America
| | - Anna Jisu Lee
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - Allison Lopatkin
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - Fan Yuan
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - Lingchong You
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
- Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, United States of America
- Center for Systems Biology, Duke University, Durham, North Carolina, United States of America
- * E-mail:
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84
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Bergsbaken T, Bevan MJ. Proinflammatory microenvironments within the intestine regulate the differentiation of tissue-resident CD8⁺ T cells responding to infection. Nat Immunol 2015; 16:406-14. [PMID: 25706747 PMCID: PMC4368475 DOI: 10.1038/ni.3108] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 01/22/2015] [Indexed: 12/12/2022]
Abstract
We report that oral infection with Yersinia pseudotuberculosis (Yptb) results in development of two distinct populations of pathogen-specific CD8 tissue-resident memory T (TRM) cells in the lamina propria (LP). CD103– T cells did not require transforming-growth factor-β (TGF-β) signaling, but were true resident memory cells. Unlike CD103+ CD8 T cells, which were TGF-β-dependent and scattered in the tissue, CD103– T cells clustered with CD4 T cells and CX3CR1+ macrophages and/or dendritic cells around areas of bacterial infection. CXCR3-dependent recruitment to inflamed areas was critical for development of the CD103– population and pathogen clearance. These studies have identified the preferential development of CD103– LP TRM cells in inflammatory microenvironments within the LP and suggest that this subset plays a critical role in controlling infection.
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Affiliation(s)
- Tessa Bergsbaken
- Department of Immunology and Howard Hughes Medical Institute, University of Washington, Seattle, Washington, USA
| | - Michael J Bevan
- Department of Immunology and Howard Hughes Medical Institute, University of Washington, Seattle, Washington, USA
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85
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86
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Suzuki H, Kondoh M, Yagi K, Kiyono H, Kunisawa J. [The development of mucosal vaccine using bacterial function for targeting mucosal tissues]. YAKUGAKU ZASSHI 2014; 134:629-34. [PMID: 24790045 DOI: 10.1248/yakushi.14-00006-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Most pathogens invade body through the mucosal epithelium, which is a primary target to prevent the infectious diseases. Mucosal vaccine has been considered to be an effective strategy to establish immunosurveillance against pathogens by the induction of antigen-specific immune responses at both mucosal and systemic immune compartments. The development of antigen delivery system and mucosal adjuvants are required for the sufficient induction of protective immunity in the development of mucosal vaccine. In this review, we shed light on the recent advances in the development of antigen delivery system using microbial functions for mucosal vaccines.
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Affiliation(s)
- Hidehiko Suzuki
- Laboratory of Vaccine Materials, National Institute of Biomedical Innovation
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87
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Heroven AK, Böhme K, Dersch P. The Csr/Rsm system of Yersinia and related pathogens. RNA Biol 2014; 9:379-91. [DOI: 10.4161/rna.19333] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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88
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Malt LM, Perrett CA, Humphrey S, Jepson MA. Applications of microscopy in Salmonella research. Methods Mol Biol 2014; 1225:165-98. [PMID: 25253256 DOI: 10.1007/978-1-4939-1625-2_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Salmonella enterica is a Gram-negative enteropathogen that can cause localized infections, typically resulting in gastroenteritis, or systemic infection, e.g., typhoid fever, in humans and many other animals. Understanding the mechanisms by which Salmonella induces disease has been the focus of intensive research. This has revealed that Salmonella invasion requires dynamic cross-talk between the microbe and host cells, in which bacterial adherence rapidly leads to a complex sequence of cellular responses initiated by proteins translocated into the host cell by a type 3 secretion system. Once these Salmonella-induced responses have resulted in bacterial invasion, proteins translocated by a second type 3 secretion system initiate further modulation of cellular activities to enable survival and replication of the invading pathogen. Elucidation of the complex and highly dynamic pathogen-host interactions ultimately requires analysis at the level of single cells and single infection events. To achieve this goal, researchers have applied a diverse range of microscopy techniques to analyze Salmonella infection in models ranging from whole animal to isolated cells and simple eukaryotic organisms. For example, electron microscopy and high-resolution light microscopy techniques such as confocal microscopy can reveal the precise location of Salmonella and its relationship to cellular components. Widefield light microscopy is a simpler approach with which to study the interaction of bacteria with host cells and often has advantages for live cell imaging, enabling detailed analysis of the dynamics of infection and cellular responses. Here we review the use of imaging techniques in Salmonella research and compare the capabilities of different classes of microscope to address specific types of research question. We also provide protocols and notes on some microscopy techniques used routinely in our own research.
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Affiliation(s)
- Layla M Malt
- Department of Biochemistry, School of Medical Sciences, University of Bristol, Tyndall Avenue, Bristol, BS8 1TD, UK
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89
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Zhang K, Dupont A, Torow N, Gohde F, Leschner S, Lienenklaus S, Weiss S, Brinkmann MM, Kühnel M, Hensel M, Fulde M, Hornef MW. Age-dependent enterocyte invasion and microcolony formation by Salmonella. PLoS Pathog 2014; 10:e1004385. [PMID: 25210785 PMCID: PMC4161480 DOI: 10.1371/journal.ppat.1004385] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 08/05/2014] [Indexed: 12/13/2022] Open
Abstract
The coordinated action of a variety of virulence factors allows Salmonella enterica to invade epithelial cells and penetrate the mucosal barrier. The influence of the age-dependent maturation of the mucosal barrier for microbial pathogenesis has not been investigated. Here, we analyzed Salmonella infection of neonate mice after oral administration. In contrast to the situation in adult animals, we observed spontaneous colonization, massive invasion of enteroabsorptive cells, intraepithelial proliferation and the formation of large intraepithelial microcolonies. Mucosal translocation was dependent on enterocyte invasion in neonates in the absence of microfold (M) cells. It further resulted in potent innate immune stimulation in the absence of pronounced neutrophil-dominated pathology. Our results identify factors of age-dependent host susceptibility and provide important insight in the early steps of Salmonella infection in vivo. We also present a new small animal model amenable to genetic manipulation of the host for the analysis of the Salmonella enterocyte interaction in vivo. Non-typhoidal Salmonella are among of the most prevalent causative agents of infectious diarrheal disease worldwide but also very significantly contribute to infant sepsis and meningitis particularly in developing countries. The underlying mechanisms of the elevated susceptibility of the infant host to systemic Salmonella infection have not been investigated. Here we analyzed age-dependent differences in the colonization, mucosal translocation and systemic spread in a murine oral infection model. We observed efficient entry of Salmonella in intestinal epithelial cells of newborn mice. Enterocyte invasion was followed by massive bacterial proliferation and the formation of large intraepithelial bacterial colonies. Intraepithelial, but not non-invasive, extracellular Salmonella induced a potent immune stimulation. Also, enterocyte invasion was required for translocation through the mucosal barrier and spread of Salmonella to systemic organs. This requirement was due to the absence of M cells, specialized epithelial cells that forward luminal antigen to the underlying immune cells, in the neonate host. Our results identify age-dependent factors of host susceptibility and illustrate the initial phase of Salmonella infection. They further present a new small animal model amenable to genetic manipulation to investigate the interaction of this pathogen with epithelial cells and characterize the early steps in Salmonella pathogenesis.
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Affiliation(s)
- Kaiyi Zhang
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Aline Dupont
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Natalia Torow
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Fredrik Gohde
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Sara Leschner
- Department of Molecular Immunology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Stefan Lienenklaus
- Department of Molecular Immunology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Siegfried Weiss
- Department of Molecular Immunology, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Melanie M. Brinkmann
- Department of Viral Immune Modulation, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
| | - Mark Kühnel
- Centre for Anatomy, Hannover Medical School, Hannover, Germany
| | - Michael Hensel
- Division of Microbiology, University of Osnabrück, Osnabrück, Germany
| | - Marcus Fulde
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
- * E-mail: (MF); (MWH)
| | - Mathias W. Hornef
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
- * E-mail: (MF); (MWH)
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90
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Thinwa J, Segovia JA, Bose S, Dube PH. Integrin-mediated first signal for inflammasome activation in intestinal epithelial cells. THE JOURNAL OF IMMUNOLOGY 2014; 193:1373-82. [PMID: 24965773 DOI: 10.4049/jimmunol.1400145] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
How intestinal epithelial cells (IECs) recognize pathogens and activate inflammasomes at intestinal surfaces is poorly understood. We hypothesized that IECs use integrin receptors to recognize pathogens and initiate inflammation within the intestinal tract. We find that IECs infected with Yersinia enterocolitica, an enteric pathogen, use β1 integrins as pathogen recognition receptors detecting the bacterial adhesin invasin (Inv). The Inv-integrin interaction provides the first signal for NLRP3 inflammasome activation with the type three secretion system translocon providing the second signal for inflammasome activation, resulting in release of IL-18. During infection, Yersinia employs two virulence factors, YopE and YopH, to counteract Inv-mediated integrin-dependent inflammasome activation. Furthermore, NLRP3 inflammasome activation in epithelial cells requires components of the focal adhesion complex signaling pathway, focal adhesion kinase, and rac1. The binding of Inv to β1 integrins rapidly induces IL-18 mRNA expression, suggesting integrins provide a first signal for NLRP3 inflammasome activation. These data suggest integrins function as pathogen recognition receptors on IECs to rapidly induce inflammasome-derived IL-18-mediated responses.
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Affiliation(s)
- Josephine Thinwa
- Department of Microbiology and Immunology, University of Texas Health Science Center, San Antonio, TX 78229; and
| | - Jesus A Segovia
- Department of Microbiology and Immunology, University of Texas Health Science Center, San Antonio, TX 78229; and Center for Airway Inflammation Research, University of Texas Health Science Center, San Antonio, TX 78229
| | - Santanu Bose
- Department of Microbiology and Immunology, University of Texas Health Science Center, San Antonio, TX 78229; and Center for Airway Inflammation Research, University of Texas Health Science Center, San Antonio, TX 78229
| | - Peter H Dube
- Department of Microbiology and Immunology, University of Texas Health Science Center, San Antonio, TX 78229; and Center for Airway Inflammation Research, University of Texas Health Science Center, San Antonio, TX 78229
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91
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Colonization of cecum is important for development of persistent infection by Yersinia pseudotuberculosis. Infect Immun 2014; 82:3471-82. [PMID: 24891107 DOI: 10.1128/iai.01793-14] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Yersiniosis is a human disease caused by the bacterium Yersinia pseudotuberculosis or Yersinia enterocolitica. The infection is usually resolved but can lead to postinfectious sequelae, including reactive arthritis and erythema nodosum. The commonly used Yersinia mouse infection model mimics acute infection in humans to some extent but leads to systemic infection and eventual death. Here, we analyzed sublethal infection doses of Y. pseudotuberculosis in mice in real time using bioluminescent imaging and found that infections using these lower doses result in extended periods of asymptomatic infections in a fraction of mice. In a search for the site for bacterial persistence, we found that the cecum was the primary colonization site and was the site where the organism resided during a 115-day infection period. Persistent infection was accompanied by sustained fecal shedding of cultivable bacteria. Cecal patches were identified as the primary site for cecal colonization during persistence. Y. pseudotuberculosis bacteria were present in inflammatory lesions, in localized foci, or as single cells and also in neutrophil exudates in the cecal lumen. The chronically colonized cecum may serve as a reservoir for dissemination of infection to extraintestinal sites, and a chronic inflammatory state may trigger the onset of postinfectious sequelae. This novel mouse model for bacterial persistence in cecum has potential as an investigative tool to unveil a deeper understanding of bacterial adaptation and host immune defense mechanisms during persistent infection.
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92
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93
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Antigen targeting to M cells for enhancing the efficacy of mucosal vaccines. Exp Mol Med 2014; 46:e85. [PMID: 24626171 PMCID: PMC3972786 DOI: 10.1038/emm.2013.165] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 12/06/2013] [Indexed: 01/01/2023] Open
Abstract
Vaccination is one of the most successful applications of immunology and for a long time has depended on parenteral administration protocols. However, recent studies have pointed to the promise of mucosal vaccination because of its ease, economy and efficiency in inducing an immune response not only systemically, but also in the mucosal compartment where many pathogenic infections are initiated. However, successful mucosal vaccination requires the help of an adjuvant for the efficient delivery of vaccine material into the mucosa and the breaking of the tolerogenic environment, especially in oral mucosal immunization. Given that M cells are the main gateway to take up luminal antigens and initiate antigen-specific immune responses, understanding the role and characteristics of M cells is crucial for the development of successful mucosal vaccines. Especially, particular interest has been focused on the regulation of the tolerogenic mucosal microenvironment and the introduction of the luminal antigen into the lymphoid organ by exploiting the molecules of M cells. Here, we review the characteristics of M cells and the immune regulatory factors in mucosa that can be exploited for mucosal vaccine delivery and mucosal immune regulation.
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94
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Gut adhesive Bacillus subtilis spores as a platform for mucosal delivery of antigens. Infect Immun 2014; 82:1414-23. [PMID: 24421038 DOI: 10.1128/iai.01255-13] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus subtilis spores have been used as safe and heat-resistant antigen delivery vectors. Nonetheless, the oral administration of spores typically induces weak immune responses to the passenger antigens, which may be attributed to the fast transit through the gastrointestinal tract. To overcome this limitation, we have developed B. subtilis spores capable of binding to the gut epithelium by means of expressing bacterial adhesins on the spore surface. The resulting spores bound to in vitro intestinal cells, showed a longer transit through the mouse intestinal tract, and interacted with Peyer's patch cells. The adhesive spores increased the systemic and secreted antibody responses to the Streptococcus mutans P1 protein, used as a model antigen, following oral, intranasal, and sublingual administration. Additionally, P1-specific antibodies efficiently inhibited the adhesion of the oral pathogen Streptococcus mutans to abiotic surfaces. These results support the use of gut-colonizing B. subtilis spores as a new platform for the mucosal delivery of vaccine antigens.
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95
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Panthani MG, Khan TA, Reid DK, Hellebusch DJ, Rasch MR, Maynard JA, Korgel BA. In vivo whole animal fluorescence imaging of a microparticle-based oral vaccine containing (CuInSe(x)S(2-x))/ZnS core/shell quantum dots. NANO LETTERS 2013; 13:4294-8. [PMID: 23915166 PMCID: PMC3796198 DOI: 10.1021/nl402054w] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Zinc sulfide-coated copper indium sulfur selenide (CuInSexS2-x/ZnS core/shell) nanocrystals were synthesized with size-tunable red to near-infrared (NIR) fluorescence with high quantum yield (40%) in water. These nanocrystals were tested as an imaging agent to track a microparticle-based oral vaccine administered to mice. Poly(lactic-co-glycolic acid) (PLGA) microparticle-encapsulated CuInSexSe2-x/ZnS quantum dots were orally administered to mice and were found to provide a distinct visible fluorescent marker in the gastrointestinal tract of living mice.
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Affiliation(s)
| | | | | | | | | | - Jennifer A. Maynard
- Corresponding authors: (T) +1-512-471-9188, (F): +1-512-471-7060, ; (T) +1-512-471-5633, (F) +1-512-471-7060k
| | - Brian A. Korgel
- Corresponding authors: (T) +1-512-471-9188, (F): +1-512-471-7060, ; (T) +1-512-471-5633, (F) +1-512-471-7060k
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96
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Abstract
The transcriptional regulator RovA positively regulates transcription of the Yersinia enterocolitica virulence gene inv. Invasin, encoded by inv, is important for establishment of Y. enterocolitica infection. However, a rovA mutant is more attenuated for virulence than an inv mutant, implying that RovA regulates additional virulence genes. When the Y. enterocolitica RovA regulon was defined by microarray analysis, YE1984 and YE1985 were among the genes identified as being upregulated by RovA. Since these genes are homologous to Xenorhabdus nematophila cytotoxin genes xaxA and xaxB, we named them yaxA and yaxB, respectively. In this work, we demonstrate the effects of YaxAB on the course of infection in the murine model. While a yaxAB mutant (ΔyaxAB) is capable of colonizing mice at the same level as the wild type, it slightly delays the course of infection and results in differing pathology in the spleen. Further, we found that yaxAB encode a probable cytotoxin capable of lysing mammalian cells, that both YaxA and YaxB are required for cytotoxic activity, and that the two proteins associate. YaxAB-mediated cell death occurs via osmotic lysis through the formation of distinct membrane pores. In silico tertiary structural analysis identified predicted structural homology between YaxA and proteins in pore-forming toxin complexes from Bacillus cereus (HBL-B) and Escherichia coli (HlyE). Thus, it appears that YaxAB function as virulence factors by inducing cell lysis through the formation of pores in the host cell membrane. This characterization of YaxAB supports the hypothesis that RovA regulates expression of multiple virulence factors in Y. enterocolitica.
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97
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No holes barred: invasion of the intestinal mucosa by Mycobacterium avium subsp. paratuberculosis. Infect Immun 2013; 81:3960-5. [PMID: 23940208 DOI: 10.1128/iai.00575-13] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The infection biology of Mycobacterium avium subsp. paratuberculosis has recently crystallized, with added details surrounding intestinal invasion. The involvement of pathogen-derived effector proteins such as the major membrane protein, oxidoreductase, and fibronectin attachment proteins have been uncovered. Mutations constructed in this pathogen have also shed light on genes needed for invasion. The host cell types that are susceptible to invasion have been defined, along with their transcriptional response. Recent details have given a new appreciation for the dynamic interplay between the host and bacterium that occurs at the outset of infection. An initial look at the global expression pathways of the host has shown a circumvention of the cell communication pathway by M. avium subsp. paratuberculosis, which loosens the integrity of the tight junctions. We now know that M. avium subsp. paratuberculosis activates the epithelial layer and also actively recruits macrophages to the site of infection. These notable findings are summarized along with added mechanistic details of the early infection model. We conclude by proposing critical next steps to further elucidate the process of M. avium subsp. paratuberculosis invasion.
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Casteleyn C, Van den Broeck W, Gebert A, Tambuyzer BR, Van Cruchten S, Van Ginneken C. M cell specific markers in man and domestic animals: Valuable tools in vaccine development. Comp Immunol Microbiol Infect Dis 2013; 36:353-64. [DOI: 10.1016/j.cimid.2013.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 03/01/2013] [Accepted: 03/21/2013] [Indexed: 12/13/2022]
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A phenotype at last: essential role for the Yersinia enterocolitica Ysa type III secretion system in a Drosophila melanogaster S2 cell model. Infect Immun 2013; 81:2478-87. [PMID: 23630961 DOI: 10.1128/iai.01454-12] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The highly pathogenic Yersinia enterocolitica strains have a chromosomally encoded type III secretion system (T3SS) that is expressed and functional in vitro only when the bacteria are cultured at 26 °C. Mutations that render this system nonfunctional are slightly attenuated in the mouse model of infection only following an oral inoculation and only at early time points postinfection. The discrepancy between the temperature required for the Ysa gene expression and the physiological temperature required for mammalian model systems has made defining the role of this T3SS challenging. Therefore, we explored the use of Drosophila S2 cells as a model system for studying Ysa function. We show here that Y. enterocolitica is capable of infecting S2 cells and replicating intracellularly to high levels, an unusual feature of this pathogen. Importantly, we show that the Ysa T3SS is required for robust intracellular replication. A secretion-deficient mutant lacking the secretin gene, ysaC, is defective in replication within S2 cells, marking the first demonstration of a pronounced Ysa-dependent virulence phenotype. Establishment of S2 cells as a model for Y. enterocolitica infection provides a versatile tool to elucidate the role of the Ysa T3SS in the life cycle of this gastrointestinal pathogen.
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100
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Grijpstra J, Arenas J, Rutten L, Tommassen J. Autotransporter secretion: varying on a theme. Res Microbiol 2013; 164:562-82. [PMID: 23567321 DOI: 10.1016/j.resmic.2013.03.010] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 02/28/2013] [Indexed: 10/27/2022]
Abstract
Autotransporters are widely distributed among Gram-negative bacteria. They can have a large variety of functions and many of them have a role in virulence. They are synthesized as large precursors with an N-terminal signal sequence that mediates transport across the inner membrane via the Sec machinery and a translocator domain that mediates the transport of the connected passenger domain across the outer membrane to the bacterial cell surface. Like integral outer membrane proteins, the translocator domain folds in a β-barrel structure and requires the Bam machinery for its insertion into the outer membrane. After transport across the outer membrane, the passenger may stay connected via the translocator domain to the bacterial cell surface or it is proteolytically released into the extracellular milieu. Based on the size of the translocator domain and its position relative to the passenger in the precursor, autotransporters are divided into four sub-categories. We review here the current knowledge of the biogenesis, structure and function of various autotransporters.
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Affiliation(s)
- Jan Grijpstra
- Section Molecular Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
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