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Papp D, Korcsmaros T, Hautefort I. Revolutionising immune research with organoid-based co-culture and chip systems. Clin Exp Immunol 2024:uxae004. [PMID: 38280212 DOI: 10.1093/cei/uxae004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Indexed: 01/29/2024] Open
Abstract
The intertwined interactions various immune cells have with epithelial cells in our body require sophisticated experimental approaches to be studied. Due to the limitations of immortalised cell lines and animal models, there is an increasing demand for human in vitro model systems to investigate the microenvironment of immune cells in normal and in pathological conditions. Organoids, which are self-renewing, 3D cellular structures that are derived from stem cells, have started to provide gap-filling tissue modelling solutions. In this review, we first demonstrate with some of the available examples how organoid-based immune cell co-culture experiments can advance disease modelling of cancer, inflammatory bowel disease and tissue regeneration. Then, we argue that to achieve both complexity and scale, organ-on-chip models combined with cutting-edge microfluidics-based technologies can provide more precise manipulation and readouts. Finally, we discuss how genome editing techniques and the use of patient-derived organoids and immune cells can improve disease modelling and facilitate precision medicine. To achieve maximum impact and efficiency, these efforts should be supported by novel infrastructures such as organoid biobanks, organoid facilities, as well as drug screening and host-microbe interaction testing platforms. All these together or in combination can allow researchers to shed more detailed, and often patient-specific, light on the crosstalk between immune cells and epithelial cells in health and disease.
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Affiliation(s)
- D Papp
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, United Kingdom
- NIHR Imperial BRC Organoid Facility, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - T Korcsmaros
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, United Kingdom
- NIHR Imperial BRC Organoid Facility, Imperial College London, Du Cane Road, London, W12 0NN, UK
- Quadram Institute, Norwich Research Park, Norwich, NR4 7UQ, United Kingdom
| | - I Hautefort
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Du Cane Road, London, W12 0NN, United Kingdom
- NIHR Imperial BRC Organoid Facility, Imperial College London, Du Cane Road, London, W12 0NN, UK
- Quadram Institute, Norwich Research Park, Norwich, NR4 7UQ, United Kingdom
- Earlham Institute, Norwich Research Park, Norwich, NR4 7UG, United Kingdom
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Demeter A, Jacomin AC, Gul L, Lister A, Lipscombe J, Invernizzi R, Branchu P, Macaulay I, Nezis IP, Kingsley RA, Korcsmaros T, Hautefort I. Computational prediction and experimental validation of Salmonella Typhimurium SopE-mediated fine-tuning of autophagy in intestinal epithelial cells. Front Cell Infect Microbiol 2022; 12:834895. [PMID: 36061866 PMCID: PMC9428466 DOI: 10.3389/fcimb.2022.834895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 07/28/2022] [Indexed: 11/13/2022] Open
Abstract
Macroautophagy is a ubiquitous homeostasis and health-promoting recycling process of eukaryotic cells, targeting misfolded proteins, damaged organelles and intracellular infectious agents. Some intracellular pathogens such as Salmonella enterica serovar Typhimurium hijack this process during pathogenesis. Here we investigate potential protein-protein interactions between host transcription factors and secreted effector proteins of Salmonella and their effect on host gene transcription. A systems-level analysis identified Salmonella effector proteins that had the potential to affect core autophagy gene regulation. The effect of a SPI-1 effector protein, SopE, that was predicted to interact with regulatory proteins of the autophagy process, was investigated to validate our approach. We then confirmed experimentally that SopE can directly bind to SP1, a host transcription factor, which modulates the expression of the autophagy gene MAP1LC3B. We also revealed that SopE might have a double role in the modulation of autophagy: Following initial increase of MAP1LC3B transcription triggered by Salmonella infection, subsequent decrease in MAP1LC3B transcription at 6h post-infection was SopE-dependent. SopE also played a role in modulation of the autophagy flux machinery, in particular MAP1LC3B and p62 autophagy proteins, depending on the level of autophagy already taking place. Upon typical infection of epithelial cells, the autophagic flux is increased. However, when autophagy was chemically induced prior to infection, SopE dampened the autophagic flux. The same was also observed when most of the intracellular Salmonella cells were not associated with the SCV (strain lacking sifA) regardless of the autophagy induction status before infection. We demonstrated how regulatory network analysis can be used to better characterise the impact of pathogenic effector proteins, in this case, Salmonella. This study complements previous work in which we had demonstrated that specific pathogen effectors can affect the autophagy process through direct interaction with autophagy proteins. Here we show that effector proteins can also influence the upstream regulation of the process. Such interdisciplinary studies can increase our understanding of the infection process and point out targets important in intestinal epithelial cell defense.
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Affiliation(s)
- Amanda Demeter
- Earlham Institute, Norwich Research Park, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich Research Park, Norwich, United Kingdom
- Department of Genetics, Eotvos Lorand University, Budapest, Hungary
| | | | - Lejla Gul
- Earlham Institute, Norwich Research Park, Norwich, United Kingdom
| | - Ashleigh Lister
- Earlham Institute, Norwich Research Park, Norwich, United Kingdom
| | - James Lipscombe
- Earlham Institute, Norwich Research Park, Norwich, United Kingdom
| | - Rachele Invernizzi
- Quadram Institute Bioscience, Norwich Research Park, Norwich, United Kingdom
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Priscilla Branchu
- Quadram Institute Bioscience, Norwich Research Park, Norwich, United Kingdom
| | - Iain Macaulay
- Earlham Institute, Norwich Research Park, Norwich, United Kingdom
| | - Ioannis P. Nezis
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Robert A. Kingsley
- Quadram Institute Bioscience, Norwich Research Park, Norwich, United Kingdom
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Tamas Korcsmaros
- Earlham Institute, Norwich Research Park, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich Research Park, Norwich, United Kingdom
- Faculty of Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
- *Correspondence: Tamas Korcsmaros,
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Hautefort I, Poletti M, Papp D, Korcsmaros T. Everything You Always Wanted to Know About Organoid-Based Models (and Never Dared to Ask). Cell Mol Gastroenterol Hepatol 2022; 14:311-331. [PMID: 35643188 PMCID: PMC9233279 DOI: 10.1016/j.jcmgh.2022.04.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 12/12/2022]
Abstract
Homeostatic functions of a living tissue, such as the gastrointestinal tract, rely on highly sophisticated and finely tuned cell-to-cell interactions. These crosstalks evolve and continuously are refined as the tissue develops and give rise to specialized cells performing general and tissue-specific functions. To study these systems, stem cell-based in vitro models, often called organoids, and non-stem cell-based primary cell aggregates (called spheroids) appeared just over a decade ago. These models still are evolving and gaining complexity, making them the state-of-the-art models for studying cellular crosstalk in the gastrointestinal tract, and to investigate digestive pathologies, such as inflammatory bowel disease, colorectal cancer, and liver diseases. However, the use of organoid- or spheroid-based models to recapitulate in vitro the highly complex structure of in vivo tissue remains challenging, and mainly restricted to expert developmental cell biologists. Here, we condense the founding knowledge and key literature information that scientists adopting the organoid technology for the first time need to consider when using these models for novel biological questions. We also include information that current organoid/spheroid users could use to add to increase the complexity to their existing models. We highlight the current and prospective evolution of these models through bridging stem cell biology with biomaterial and scaffold engineering research areas. Linking these complementary fields will increase the in vitro mimicry of in vivo tissue, and potentially lead to more successful translational biomedical applications. Deepening our understanding of the nature and dynamic fine-tuning of intercellular crosstalks will enable identifying novel signaling targets for new or repurposed therapeutics used in many multifactorial diseases.
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Affiliation(s)
- Isabelle Hautefort
- Earlham Institute, Organisms and Ecosystems Programme, Norwich, United Kingdom
| | - Martina Poletti
- Earlham Institute, Organisms and Ecosystems Programme, Norwich, United Kingdom; Quadram Institute Bioscience, Gut Microbes and Health Programme, Norwich, United Kingdom
| | - Diana Papp
- Quadram Institute Bioscience, Gut Microbes and Health Programme, Norwich, United Kingdom
| | - Tamas Korcsmaros
- Earlham Institute, Organisms and Ecosystems Programme, Norwich, United Kingdom; Quadram Institute Bioscience, Gut Microbes and Health Programme, Norwich, United Kingdom; Imperial College London, Department of Metabolism, Digestion and Reproduction, London, United Kingdom.
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Olbei M, Thomas JP, Hautefort I, Treveil A, Bohar B, Madgwick M, Gul L, Csabai L, Modos D, Korcsmaros T. CytokineLink: A Cytokine Communication Map to Analyse Immune Responses-Case Studies in Inflammatory Bowel Disease and COVID-19. Cells 2021; 10:2242. [PMID: 34571891 PMCID: PMC8469673 DOI: 10.3390/cells10092242] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 08/27/2021] [Accepted: 08/27/2021] [Indexed: 11/16/2022] Open
Abstract
Intercellular communication mediated by cytokines is critical to the development of immune responses, particularly in the context of infectious and inflammatory diseases. By releasing these small molecular weight peptides, the source cells can influence numerous intracellular processes in the target cells, including the secretion of other cytokines downstream. However, there are no readily available bioinformatic resources that can model cytokine-cytokine interactions. In this effort, we built a communication map between major tissues and blood cells that reveals how cytokine-mediated intercellular networks form during homeostatic conditions. We collated the most prevalent cytokines from the literature and assigned the proteins and their corresponding receptors to source tissue and blood cell types based on enriched consensus RNA-Seq data from the Human Protein Atlas database. To assign more confidence to the interactions, we integrated the literature information on cell-cytokine interactions from two systems of immunology databases, immuneXpresso and ImmunoGlobe. From the collated information, we defined two metanetworks: a cell-cell communication network connected by cytokines; and a cytokine-cytokine interaction network depicting the potential ways in which cytokines can affect the activity of each other. Using expression data from disease states, we then applied this resource to reveal perturbations in cytokine-mediated intercellular signalling in inflammatory and infectious diseases (ulcerative colitis and COVID-19, respectively). For ulcerative colitis, with CytokineLink, we demonstrated a significant rewiring of cytokine-mediated intercellular communication between non-inflamed and inflamed colonic tissues. For COVID-19, we were able to identify cell types and cytokine interactions following SARS-CoV-2 infection, highlighting important cytokine interactions that might contribute to severe illness in a subgroup of patients. Such findings have the potential to inform the development of novel, cytokine-targeted therapeutic strategies. CytokineLink is freely available for the scientific community through the NDEx platform and the project github repository.
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Affiliation(s)
- Marton Olbei
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Quadram Institute Bioscience, Norwich NR4 7UZ, UK
| | - John P. Thomas
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Quadram Institute Bioscience, Norwich NR4 7UZ, UK
- Department of Gastroenterology, Norfolk and Norwich University Hospital, Norwich NR4 7UZ, UK
| | - Isabelle Hautefort
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
| | - Agatha Treveil
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Quadram Institute Bioscience, Norwich NR4 7UZ, UK
| | - Balazs Bohar
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Department of Genetics, Eotvos Lorand University, 1117 Budapest, Hungary
| | - Matthew Madgwick
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Quadram Institute Bioscience, Norwich NR4 7UZ, UK
| | - Lejla Gul
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
| | - Luca Csabai
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Department of Genetics, Eotvos Lorand University, 1117 Budapest, Hungary
| | - Dezso Modos
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Quadram Institute Bioscience, Norwich NR4 7UZ, UK
| | - Tamas Korcsmaros
- Earlham Institute, Norwich NR4 7UZ, UK; (M.O.); (J.P.T.); (I.H.); (A.T.); (B.B.); (M.M.); (L.G.); (L.C.); (D.M.)
- Quadram Institute Bioscience, Norwich NR4 7UZ, UK
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Olbei M, Hautefort I, Modos D, Treveil A, Poletti M, Gul L, Shannon-Lowe CD, Korcsmaros T. SARS-CoV-2 Causes a Different Cytokine Response Compared to Other Cytokine Storm-Causing Respiratory Viruses in Severely Ill Patients. Front Immunol 2021; 12:629193. [PMID: 33732251 PMCID: PMC7956943 DOI: 10.3389/fimmu.2021.629193] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/29/2021] [Indexed: 12/21/2022] Open
Abstract
Hyper-induction of pro-inflammatory cytokines, also known as a cytokine storm or cytokine release syndrome (CRS), is one of the key aspects of the currently ongoing SARS-CoV-2 pandemic. This process occurs when a large number of innate and adaptive immune cells activate and start producing pro-inflammatory cytokines, establishing an exacerbated feedback loop of inflammation. It is one of the factors contributing to the mortality observed with coronavirus 2019 (COVID-19) for a subgroup of patients. CRS is not unique to the SARS-CoV-2 infection; it was prevalent in most of the major human coronavirus and influenza A subtype outbreaks of the past two decades (H5N1, SARS-CoV, MERS-CoV, and H7N9). With a comprehensive literature search, we collected changing the cytokine levels from patients upon infection with the viral pathogens mentioned above. We analyzed published patient data to highlight the conserved and unique cytokine responses caused by these viruses. Our curation indicates that the cytokine response induced by SARS-CoV-2 is different compared to other CRS-causing respiratory viruses, as SARS-CoV-2 does not always induce specific cytokines like other coronaviruses or influenza do, such as IL-2, IL-10, IL-4, or IL-5. Comparing the collated cytokine responses caused by the analyzed viruses highlights a SARS-CoV-2-specific dysregulation of the type-I interferon (IFN) response and its downstream cytokine signatures. The map of responses gathered in this study could help specialists identify interventions that alleviate CRS in different diseases and evaluate whether they could be used in the COVID-19 cases.
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Affiliation(s)
- Marton Olbei
- Earlham Institute, Norwich, United Kingdom
- Gut Microbes and Health Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | | | - Dezso Modos
- Earlham Institute, Norwich, United Kingdom
- Gut Microbes and Health Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Agatha Treveil
- Earlham Institute, Norwich, United Kingdom
- Gut Microbes and Health Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Martina Poletti
- Earlham Institute, Norwich, United Kingdom
- Gut Microbes and Health Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Lejla Gul
- Earlham Institute, Norwich, United Kingdom
| | - Claire D. Shannon-Lowe
- Institute of Immunology and Immunotherapy, The University of Birmingham, Birmingham, United Kingdom
| | - Tamas Korcsmaros
- Earlham Institute, Norwich, United Kingdom
- Gut Microbes and Health Programme, Quadram Institute Bioscience, Norwich, United Kingdom
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Treveil A, Bohar B, Sudhakar P, Gul L, Csabai L, Olbei M, Poletti M, Madgwick M, Andrighetti T, Hautefort I, Modos D, Korcsmaros T. ViralLink: An integrated workflow to investigate the effect of SARS-CoV-2 on intracellular signalling and regulatory pathways. PLoS Comput Biol 2021; 17:e1008685. [PMID: 33534793 PMCID: PMC7886129 DOI: 10.1371/journal.pcbi.1008685] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 02/16/2021] [Accepted: 01/10/2021] [Indexed: 12/21/2022] Open
Abstract
The SARS-CoV-2 pandemic of 2020 has mobilised scientists around the globe to research all aspects of the coronavirus virus and its infection. For fruitful and rapid investigation of viral pathomechanisms, a collaborative and interdisciplinary approach is required. Therefore, we have developed ViralLink: a systems biology workflow which reconstructs and analyses networks representing the effect of viruses on intracellular signalling. These networks trace the flow of signal from intracellular viral proteins through their human binding proteins and downstream signalling pathways, ending with transcription factors regulating genes differentially expressed upon viral exposure. In this way, the workflow provides a mechanistic insight from previously identified knowledge of virally infected cells. By default, the workflow is set up to analyse the intracellular effects of SARS-CoV-2, requiring only transcriptomics counts data as input from the user: thus, encouraging and enabling rapid multidisciplinary research. However, the wide-ranging applicability and modularity of the workflow facilitates customisation of viral context, a priori interactions and analysis methods. Through a case study of SARS-CoV-2 infected bronchial/tracheal epithelial cells, we evidence the functionality of the workflow and its ability to identify key pathways and proteins in the cellular response to infection. The application of ViralLink to different viral infections in a context specific manner using different available transcriptomics datasets will uncover key mechanisms in viral pathogenesis.
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Affiliation(s)
- Agatha Treveil
- Earlham Institute, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich, United Kingdom
| | - Balazs Bohar
- Earlham Institute, Norwich, United Kingdom
- Department of Genetics, Eotvos Lorand University, Budapest, Hungary
| | - Padhmanand Sudhakar
- Earlham Institute, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich, United Kingdom
- Department of Chronic Diseases, Metabolism and Ageing, Translational Research Center for Gastrointestinal Disorders, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Lejla Gul
- Earlham Institute, Norwich, United Kingdom
| | - Luca Csabai
- Earlham Institute, Norwich, United Kingdom
- Department of Genetics, Eotvos Lorand University, Budapest, Hungary
| | - Marton Olbei
- Earlham Institute, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich, United Kingdom
| | - Martina Poletti
- Earlham Institute, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich, United Kingdom
| | - Matthew Madgwick
- Earlham Institute, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich, United Kingdom
| | - Tahila Andrighetti
- Earlham Institute, Norwich, United Kingdom
- Institute of Biosciences, São Paulo University, Botucatu, Brazil
| | | | - Dezso Modos
- Earlham Institute, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich, United Kingdom
| | - Tamas Korcsmaros
- Earlham Institute, Norwich, United Kingdom
- Quadram Institute Bioscience, Norwich, United Kingdom
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Treveil A, Sudhakar P, Matthews ZJ, Wrzesiński T, Jones EJ, Brooks J, Ölbei M, Hautefort I, Hall LJ, Carding SR, Mayer U, Powell PP, Wileman T, Di Palma F, Haerty W, Korcsmáros T. Regulatory network analysis of Paneth cell and goblet cell enriched gut organoids using transcriptomics approaches. Mol Omics 2021; 16:39-58. [PMID: 31819932 DOI: 10.1039/c9mo00130a] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The epithelial lining of the small intestine consists of multiple cell types, including Paneth cells and goblet cells, that work in cohort to maintain gut health. 3D in vitro cultures of human primary epithelial cells, called organoids, have become a key model to study the functions of Paneth cells and goblet cells in normal and diseased conditions. Advances in these models include the ability to skew differentiation to particular lineages, providing a useful tool to study cell type specific function/dysfunction in the context of the epithelium. Here, we use comprehensive profiling of mRNA, microRNA and long non-coding RNA expression to confirm that Paneth cell and goblet cell enrichment of murine small intestinal organoids (enteroids) establishes a physiologically accurate model. We employ network analysis to infer the regulatory landscape altered by skewing differentiation, and using knowledge of cell type specific markers, we predict key regulators of cell type specific functions: Cebpa, Jun, Nr1d1 and Rxra specific to Paneth cells, Gfi1b and Myc specific for goblet cells and Ets1, Nr3c1 and Vdr shared between them. Links identified between these regulators and cellular phenotypes of inflammatory bowel disease (IBD) suggest that global regulatory rewiring during or after differentiation of Paneth cells and goblet cells could contribute to IBD aetiology. Future application of cell type enriched enteroids combined with the presented computational workflow can be used to disentangle multifactorial mechanisms of these cell types and propose regulators whose pharmacological targeting could be advantageous in treating IBD patients with Crohn's disease or ulcerative colitis.
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Affiliation(s)
- A Treveil
- Earlham Institute, Norwich Research Park, Norwich, Norfolk NR4 7UZ, UK.
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Jones EJ, Booth C, Fonseca S, Parker A, Cross K, Miquel-Clopés A, Hautefort I, Mayer U, Wileman T, Stentz R, Carding SR. The Uptake, Trafficking, and Biodistribution of Bacteroides thetaiotaomicron Generated Outer Membrane Vesicles. Front Microbiol 2020; 11:57. [PMID: 32117106 PMCID: PMC7015872 DOI: 10.3389/fmicb.2020.00057] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 01/13/2020] [Indexed: 12/29/2022] Open
Abstract
Gram-negative bacteria ubiquitously produce and release nano-size, non-replicative outer membrane vesicles (OMVs). In the gastrointestinal (GI-) tract, OMVs generated by members of the intestinal microbiota are believed to contribute to maintaining the intestinal microbial ecosystem and mediating bacteria-host interactions, including the delivery of bacterial effector molecules to host cells to modulate their physiology. Bacterial OMVs have also been found in the bloodstream although their origin and fate are unclear. Here we have investigated the interactions between OMVs produced by the major human gut commensal bacterium, Bacteroides thetaiotaomicron (Bt), with cells of the GI-tract. Using a combination of in vitro culture systems including intestinal epithelial organoids and in vivo imaging we show that intestinal epithelial cells principally acquire Bt OMVs via dynamin-dependent endocytosis followed by intracellular trafficking to LAMP-1 expressing endo-lysosomal vesicles and co-localization with the perinuclear membrane. We observed that Bt OMVs can also transmigrate through epithelial cells via a paracellular route with in vivo imaging demonstrating that within hours of oral administration Bt OMVs can be detected in systemic tissues and in particular, the liver. Our findings raise the intriguing possibility that OMVs may act as a long-distance microbiota-host communication system.
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Affiliation(s)
- Emily J. Jones
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Catherine Booth
- Core Science Resources, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Sonia Fonseca
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Aimee Parker
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Kathryn Cross
- Core Science Resources, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Ariadna Miquel-Clopés
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | | | - Ulrike Mayer
- Biomedical Research Centre, University of East Anglia, Norwich, United Kingdom
| | - Tom Wileman
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, United Kingdom
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
| | - Régis Stentz
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, United Kingdom
| | - Simon R. Carding
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, United Kingdom
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
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Sudhakar P, Jacomin AC, Hautefort I, Samavedam S, Fatemian K, Ari E, Gul L, Demeter A, Jones E, Korcsmaros T, Nezis IP. Targeted interplay between bacterial pathogens and host autophagy. Autophagy 2019; 15:1620-1633. [PMID: 30909843 PMCID: PMC6693458 DOI: 10.1080/15548627.2019.1590519] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 02/21/2019] [Accepted: 03/01/2019] [Indexed: 12/12/2022] Open
Abstract
Due to the critical role played by autophagy in pathogen clearance, pathogens have developed diverse strategies to subvert it. Despite previous key findings of bacteria-autophagy interplay, asystems-level insight into selective targeting by the host and autophagy modulation by the pathogens is lacking. We predicted potential interactions between human autophagy proteins and effector proteins from 56 pathogenic bacterial species by identifying bacterial proteins predicted to have recognition motifs for selective autophagy receptors SQSTM1/p62, CALCOCO2/NDP52 and MAP1LC3/LC3. Using structure-based interaction prediction, we identified bacterial proteins capable to modify core autophagy components. Our analysis revealed that autophagy receptors in general potentially target mostly genus-specific proteins, and not those present in multiple genera. The complementarity between the predicted SQSTM1/p62 and CALCOCO2/NDP52 targets, which has been shown for Salmonella, Listeria and Shigella, could be observed across other pathogens. This complementarity potentially leaves the host more susceptible to chronic infections upon the mutation of autophagy receptors. Proteins derived from enterotoxigenic and non-toxigenic Bacillus outer membrane vesicles indicated that autophagy targets pathogenic proteins rather than non-pathogenic ones. We also observed apathogen-specific pattern as to which autophagy phase could be modulated by specific genera. We found intriguing examples of bacterial proteins that could modulate autophagy, and in turn being targeted by autophagy as ahost defense mechanism. We confirmed experimentally an interplay between a Salmonella protease, YhjJ and autophagy. Our comparative meta-analysis points out key commonalities and differences in how pathogens could affect autophagy and how autophagy potentially recognizes these pathogenic effectors. Abbreviations: ATG5: autophagy related 5; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; GST: glutathione S-transferase; LIR: MAP1LC3/LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3 alpha; OMV: outer membrane vesicles; SQSTM1/p62: sequestosome 1; SCV: Salmonella containing vesicle; TECPR1: tectonin beta-propeller repeat containing 1; YhjJ: hypothetical zinc-protease.
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Affiliation(s)
- Padhmanand Sudhakar
- Earlham Institute, Norwich Research Park, Norwich, UK
- Gut Health and Microbes Programme, Quadram Institute, Norwich Research Park, Norwich, UK
- Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | | | | | - Siva Samavedam
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Koorosh Fatemian
- School of Life Sciences, University of Warwick, Coventry, UK
- Current affiliation:Exaelements LTD, Coventry, UK
| | - Eszter Ari
- Department of Genetics, Eotvos Lorand University, Budapest, Hungary
- Synthetic and System Biology Unit, Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Leila Gul
- Earlham Institute, Norwich Research Park, Norwich, UK
| | - Amanda Demeter
- Earlham Institute, Norwich Research Park, Norwich, UK
- Gut Health and Microbes Programme, Quadram Institute, Norwich Research Park, Norwich, UK
- Department of Genetics, Eotvos Lorand University, Budapest, Hungary
| | - Emily Jones
- Earlham Institute, Norwich Research Park, Norwich, UK
- Gut Health and Microbes Programme, Quadram Institute, Norwich Research Park, Norwich, UK
| | - Tamas Korcsmaros
- Earlham Institute, Norwich Research Park, Norwich, UK
- Gut Health and Microbes Programme, Quadram Institute, Norwich Research Park, Norwich, UK
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10
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Jones EJ, Matthews ZJ, Gul L, Sudhakar P, Treveil A, Divekar D, Buck J, Wrzesinski T, Jefferson M, Armstrong SD, Hall LJ, Watson AJM, Carding SR, Haerty W, Di Palma F, Mayer U, Powell PP, Hautefort I, Wileman T, Korcsmaros T. Integrative analysis of Paneth cell proteomic and transcriptomic data from intestinal organoids reveals functional processes dependent on autophagy. Dis Model Mech 2019; 12:dmm.037069. [PMID: 30814064 PMCID: PMC6451430 DOI: 10.1242/dmm.037069] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 02/01/2019] [Indexed: 12/12/2022] Open
Abstract
Paneth cells are key epithelial cells that provide an antimicrobial barrier and maintain integrity of the small-intestinal stem cell niche. Paneth cell abnormalities are unfortunately detrimental to gut health and are often associated with digestive pathologies such as Crohn's disease or infections. Similar alterations are observed in individuals with impaired autophagy, a process that recycles cellular components. The direct effect of autophagy impairment on Paneth cells has not been analysed. To investigate this, we generated a mouse model lacking Atg16l1 specifically in intestinal epithelial cells, making these cells impaired in autophagy. Using three-dimensional intestinal organoids enriched for Paneth cells, we compared the proteomic profiles of wild-type and autophagy-impaired organoids. We used an integrated computational approach combining protein-protein interaction networks, autophagy-targeted proteins and functional information to identify the mechanistic link between autophagy impairment and disrupted pathways. Of the 284 altered proteins, 198 (70%) were more abundant in autophagy-impaired organoids, suggesting reduced protein degradation. Interestingly, these differentially abundant proteins comprised 116 proteins (41%) that are predicted targets of the selective autophagy proteins p62, LC3 and ATG16L1. Our integrative analysis revealed autophagy-mediated mechanisms that degrade key proteins in Paneth cell functions, such as exocytosis, apoptosis and DNA damage repair. Transcriptomic profiling of additional organoids confirmed that 90% of the observed changes upon autophagy alteration have effects at the protein level, not on gene expression. We performed further validation experiments showing differential lysozyme secretion, confirming our computationally inferred downregulation of exocytosis. Our observations could explain how protein-level alterations affect Paneth cell homeostatic functions upon autophagy impairment. This article has an associated First Person interview with the joint first authors of the paper. Editor's choice: Using an integrative approach encompassing intestinal organoid culture, proteomics, transcriptomics and protein-protein interaction networks, we list Paneth cell functions dependent on autophagy.
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Affiliation(s)
- Emily J Jones
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK.,Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK.,Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Zoe J Matthews
- Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Lejla Gul
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK
| | - Padhmanand Sudhakar
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK.,Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK
| | - Agatha Treveil
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK.,Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK
| | - Devina Divekar
- Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK.,Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Jasmine Buck
- Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | | | - Matthew Jefferson
- Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Stuart D Armstrong
- National Institute of Health Research, University of Liverpool, Liverpool L3 5RF, UK
| | - Lindsay J Hall
- Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK
| | - Alastair J M Watson
- Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK.,Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Simon R Carding
- Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK.,Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Wilfried Haerty
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK
| | | | - Ulrike Mayer
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - Penny P Powell
- Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | | | - Tom Wileman
- Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK.,Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Tamas Korcsmaros
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK .,Quadram Institute, Norwich Research Park, Norwich NR4 7UA, UK
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11
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Fuell C, Kober OI, Hautefort I, Juge N. Mice deficient in intestinal γδ intraepithelial lymphocytes display an altered intestinal O-glycan profile compared with wild-type littermates. Glycobiology 2014; 25:42-54. [PMID: 25187161 DOI: 10.1093/glycob/cwu088] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intestinal γδ T-cell receptor-bearing intraepithelial lymphocytes (γδ IELs) play a multifaceted role in maintaining mucosal homeostasis. In order to investigate the relationship between O-glycosylation and inflammation, we carried out an in-depth mass spectrometric comparison of the intestinal O-glycosylation profile of mice lacking γδ IELs (TCRδ(-/-)) and of their wild-type (WT) littermates. A total of 69 nonsulfated and 59 sulfated compositional types of O-glycans were identified in the small intestine and colon of TCRδ(-/-) and WT mice. Our results demonstrated structural differences in intestinal glycosylation in TCRδ(-/-) mice compared with WT littermates. TCRδ(-/-) colons contained a lower proportion of core-2 structures and an increased proportion of core-1 structures whereas TCRδ(-/-) small intestines had a decreased percentage of core-3 structures. The glycan antennae in TCRδ(-/-) colon and small intestine showed altered structural diversity compared with WT mice. There were significant differences in the sialylated species between the TCRδ(-/-) and WT mice with the sialylated Tn antigen found exclusively in the TCRδ(-/-)small intestine, whereas the sulfation pattern remained mostly unchanged. These findings provide novel molecular insights underpinning the role of γδ IELs in maintaining gut homeostasis.
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Affiliation(s)
- Christine Fuell
- Gut Health and Food Safety Institute Strategic Programme, Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK
| | - Olivia I Kober
- Gut Health and Food Safety Institute Strategic Programme, Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK
| | - Isabelle Hautefort
- Gut Health and Food Safety Institute Strategic Programme, Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK
| | - Nathalie Juge
- Gut Health and Food Safety Institute Strategic Programme, Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK
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12
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Stentz R, Osborne S, Horn N, Li AWH, Hautefort I, Bongaerts R, Rouyer M, Bailey P, Shears SB, Hemmings AM, Brearley CA, Carding SR. A bacterial homolog of a eukaryotic inositol phosphate signaling enzyme mediates cross-kingdom dialog in the mammalian gut. Cell Rep 2014; 6:646-56. [PMID: 24529702 PMCID: PMC3969271 DOI: 10.1016/j.celrep.2014.01.021] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 12/13/2013] [Accepted: 01/15/2014] [Indexed: 11/25/2022] Open
Abstract
Dietary InsP6 can modulate eukaryotic cell proliferation and has complex nutritive consequences, but its metabolism in the mammalian gastrointestinal tract is poorly understood. Therefore, we performed phylogenetic analyses of the gastrointestinal microbiome in order to search for candidate InsP6 phosphatases. We determined that prominent gut bacteria express homologs of the mammalian InsP6 phosphatase (MINPP) and characterized the enzyme from Bacteroides thetaiotaomicron (BtMinpp). We show that BtMinpp has exceptionally high catalytic activity, which we rationalize on the basis of mutagenesis studies and by determining its crystal structure at 1.9 Å resolution. We demonstrate that BtMinpp is packaged inside outer membrane vesicles (OMVs) protecting the enzyme from degradation by gastrointestinal proteases. Moreover, we uncover an example of cross-kingdom cell-to-cell signaling, showing that the BtMinpp-OMVs interact with intestinal epithelial cells to promote intracellular Ca2+ signaling. Our characterization of BtMinpp offers several directions for understanding how the microbiome serves human gastrointestinal physiology. Bacteroides thetaiotaomicron (Bt) secretes a cell-signaling InsP6 phosphatase MINPP BtMinpp is exceptionally active and rationalized from its crystal structure BtMinpp is secreted in outermembrane vesicles BtMinpp/OMVs promote Ca2+ signaling in intestinal epithelial cells
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Affiliation(s)
- Régis Stentz
- Gut Health and Food Safety Programme, Institute of Food Research, Norwich NR4 7UA, UK
| | - Samantha Osborne
- Gut Health and Food Safety Programme, Institute of Food Research, Norwich NR4 7UA, UK
| | - Nikki Horn
- Gut Health and Food Safety Programme, Institute of Food Research, Norwich NR4 7UA, UK
| | - Arthur W H Li
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - Isabelle Hautefort
- Gut Health and Food Safety Programme, Institute of Food Research, Norwich NR4 7UA, UK
| | - Roy Bongaerts
- Gut Health and Food Safety Programme, Institute of Food Research, Norwich NR4 7UA, UK
| | - Marine Rouyer
- Gut Health and Food Safety Programme, Institute of Food Research, Norwich NR4 7UA, UK
| | - Paul Bailey
- Department of Computational and Systems Biology, John Innes Centre, Norwich NR4 7UH, UK
| | - Stephen B Shears
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Andrew M Hemmings
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK; School of Chemistry, University of East Anglia, Norwich NR4 7TJ, UK
| | - Charles A Brearley
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
| | - Simon R Carding
- Gut Health and Food Safety Programme, Institute of Food Research, Norwich NR4 7UA, UK; Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK.
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13
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Walker CR, Hautefort I, Dalton JE, Overweg K, Egan CE, Bongaerts RJ, Newton DJ, Cruickshank SM, Andrew EM, Carding SR. Intestinal intraepithelial lymphocyte-enterocyte crosstalk regulates production of bactericidal angiogenin 4 by Paneth cells upon microbial challenge. PLoS One 2013; 8:e84553. [PMID: 24358364 PMCID: PMC3866140 DOI: 10.1371/journal.pone.0084553] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 11/15/2013] [Indexed: 02/07/2023] Open
Abstract
Antimicrobial proteins influence intestinal microbial ecology and limit proliferation of pathogens, yet the regulation of their expression has only been partially elucidated. Here, we have identified a putative pathway involving epithelial cells and intestinal intraepithelial lymphocytes (iIELs) that leads to antimicrobial protein (AMP) production by Paneth cells. Mice lacking γδ iIELs (TCRδ(-/-)) express significantly reduced levels of the AMP angiogenin 4 (Ang4). These mice were also unable to up-regulate Ang4 production following oral challenge by Salmonella, leading to higher levels of mucosal invasion compared to their wild type counterparts during the first 2 hours post-challenge. The transfer of γδ iIELs from wild type (WT) mice to TCRδ(-/-) mice restored Ang4 production and Salmonella invasion levels were reduced to those obtained in WT mice. The ability to restore Ang4 production in TCRδ(-/-) mice was shown to be restricted to γδ iIELs expressing Vγ7-encoded TCRs. Using a novel intestinal crypt co-culture system we identified a putative pathway of Ang4 production initiated by exposure to Salmonella, intestinal commensals or microbial antigens that induced intestinal epithelial cells to produce cytokines including IL‑23 in a TLR-mediated manner. Exposure of TCR-Vγ7(+) γδ iIELs to IL-23 promoted IL‑22 production, which triggered Paneth cells to secrete Ang4. These findings identify a novel role for γδ iIELs in mucosal defence through sensing immediate epithelial cell cytokine responses and influencing AMP production. This in turn can contribute to the maintenance of intestinal microbial homeostasis and epithelial barrier function, and limit pathogen invasion.
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Affiliation(s)
- Catherine R. Walker
- Gut Health and Food Safety, Institute of Food Research, Norwich, United Kingdom
- Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Isabelle Hautefort
- Gut Health and Food Safety, Institute of Food Research, Norwich, United Kingdom
| | - Jane E. Dalton
- Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Centre for Immunology and Infection, University of York, York, United Kingdom
| | - Karin Overweg
- Gut Health and Food Safety, Institute of Food Research, Norwich, United Kingdom
| | - Charlotte E. Egan
- Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Pediatric Surgery, Children’s Hospital of Pittsburgh, UPMC, Pittsburgh, Pennsylvania, United States of America
| | - Roy J. Bongaerts
- Gut Health and Food Safety, Institute of Food Research, Norwich, United Kingdom
| | - Darren J. Newton
- Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Leeds Institute of Cancer & Pathology, Wellcome Trust Brenner Building, St James’s University Hospital, Leeds, United Kingdom
| | - Sheena M. Cruickshank
- Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Elizabeth M. Andrew
- Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Simon R. Carding
- Gut Health and Food Safety, Institute of Food Research, Norwich, United Kingdom
- Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
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14
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Wright JA, Tötemeyer SS, Hautefort I, Appia-Ayme C, Alston M, Danino V, Paterson GK, Mastroeni P, Ménager N, Rolfe M, Thompson A, Ugrinovic S, Sait L, Humphrey T, Northen H, Peters SE, Maskell DJ, Hinton JCD, Bryant CE. Multiple redundant stress resistance mechanisms are induced in Salmonella enterica serovar Typhimurium in response to alteration of the intracellular environment via TLR4 signalling. Microbiology (Reading) 2009; 155:2919-2929. [PMID: 19542004 DOI: 10.1099/mic.0.030429-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Toll-like receptor 4 (TLR4) senses bacterial LPS and is required for the control of systemic Salmonella enterica serovar Typhimurium infection in mice. The mechanisms of TLR4 activation and its downstream signalling cascades are well described, yet the direct effects on the pathogen of signalling via this receptor remain unknown. To investigate this we used microarray-based transcriptome profiling of intracellular S. Typhimurium during infection of primary bone marrow-derived macrophages from wild-type and TLR4-deficient mice. We identified 17 S. Typhimurium genes that were upregulated in the presence of functional TLR4. Nine of these genes have putative functions in oxidative stress resistance. We therefore examined S. Typhimurium gene expression during infection of NADPH oxidase-deficient macrophages, which lack normal oxidative killing mechanisms. We identified significant overlap between the 'TLR4-responsive' and 'NADPH oxidase-responsive' genes. This is new evidence for a link between TLR4 signalling and NADPH oxidase activity. Interestingly, with the exception of a dps mutant, S. Typhimurium strains lacking individual TLR4- and/or oxidative stress-responsive genes were not attenuated during intravenous murine infections. Our study shows that TLR4 activity, either directly or indirectly, induces the expression of multiple stress resistance genes during the intracellular life of S. Typhimurium.
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Affiliation(s)
- John A Wright
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Sabine S Tötemeyer
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Isabelle Hautefort
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK
| | - Corinne Appia-Ayme
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK
| | - Mark Alston
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK
| | - Vittoria Danino
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK
| | - Gavin K Paterson
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Pietro Mastroeni
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Nathalie Ménager
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Matthew Rolfe
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK
| | - Arthur Thompson
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK
| | - Sanja Ugrinovic
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Leanne Sait
- School of Clinical Veterinary Sciences, University of Bristol, Langford House, Langford, Bristol BS40 5DU, UK
| | - Tom Humphrey
- School of Clinical Veterinary Sciences, University of Bristol, Langford House, Langford, Bristol BS40 5DU, UK
| | - Helen Northen
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Sarah E Peters
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Duncan J Maskell
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Jay C D Hinton
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK
| | - Clare E Bryant
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
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15
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Arques JL, Hautefort I, Ivory K, Bertelli E, Regoli M, Clare S, Hinton JCD, Nicoletti C. Salmonella induces flagellin- and MyD88-dependent migration of bacteria-capturing dendritic cells into the gut lumen. Gastroenterology 2009; 137:579-87, 587.e1-2. [PMID: 19375423 DOI: 10.1053/j.gastro.2009.04.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 02/15/2009] [Accepted: 04/09/2009] [Indexed: 12/24/2022]
Abstract
BACKGROUND & AIMS Intestinal dendritic cells (DCs) sample bacteria, such as Salmonella, by extending cellular processes into the lumen to capture bacteria and shuttle them across the epithelium; however, direct evidence of bacteria-loaded DCs travelling back into the tissue is lacking. We hypothesized that sampling is paralleled by migration of DCs into the lumen prior to or following the internalization of Salmonella. METHODS The small intestine and the colon of BALB/c and C57BL/6 mice were challenged with noninvasive Salmonella enterica serovar Typhimurium SL1344-DeltaSalmonella pathogenicity island (SPI) 1 or Escherichia coli DH5alpha by using isolated loops or oral administration by gavage. Transepithelial migration of DCs was documented by immunohistochemistry, microscopy, and flow cytometry. The role of flagellin was determined by using flagellin (DeltafliC DeltafljB)- and SPI1-SPI2 (DeltaSPI1 DeltassrA)-deficient Salmonella, flagellated E coli K12, and MyD88 mice. RESULTS Salmonella DeltaSPI1 induced migration of CD11c(+)CX(3)CR1(+)MHCII(+)CD11b(-)CD8alpha(-) DCs into the small intestine, whereas flagellin- and SPI1-SPI2-deficient Salmonella, soluble flagellin, and E coli DH5alpha or flagellated K12, failed to do so. DC migration did not occur in the colon; it was not observed in MyD88 mice, and intraluminal DCs internalized Salmonella but did not cross the epithelium to return into tissues. Finally, DC migration was not linked to Salmonella-induced damage of the epithelium. CONCLUSIONS DC-mediated sampling of Salmonella is accompanied by flagellin- and MyD88-dependent migration of Salmonella-capturing DCs into the intestinal lumen. We suggest that the rapid intraluminal migration of Salmonella-capturing DCs may play a role in the protection of the intestinal mucosa against bacterial infection.
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Affiliation(s)
- Juan L Arques
- Programme of GI Tract Biology, Institute of Food Research, Norwich, United Kingdom
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16
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Hautefort I. Adhesion to the digestive mucosa is not sufficient for durable persistence of differentLactobacillus fermentumstrains in the digestive tract of mice. Microbial Ecology in Health and Disease 2009. [DOI: 10.1080/089106000435590] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- I. Hautefort
- U.E.P.S.D. Bât. 440, I.N.R.A.-C.R.J. Domaine de Vilvert, 78352 Jouy-en-Josas, France
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17
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Bertelli E, Regoli M, Clare S, Hautefort I, Hinton J, Ivory K, Nicoletti C, Arques J. Salmonella enterica serovar Typhimurium Induces Rapid Migration of Dendritic Cells into the Gut Lumen. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.852.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Marì Regoli
- Dept of PharmacologyUniversity of SienaSienaItaly
| | - Simon Clare
- Wellcome Trust Sanger InstituteCambridgeUnited Kingdom
| | | | - Jay Hinton
- Institute for Food ResearchNorwichUnited Kingdom
| | - Kamal Ivory
- Institute for Food ResearchNorwichUnited Kingdom
| | | | - Juan Arques
- Institute for Food ResearchNorwichUnited Kingdom
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18
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Hautefort I, Thompson A, Eriksson-Ygberg S, Parker ML, Lucchini S, Danino V, Bongaerts RJM, Ahmad N, Rhen M, Hinton JCD. During infection of epithelial cells Salmonella enterica serovar Typhimurium undergoes a time-dependent transcriptional adaptation that results in simultaneous expression of three type 3 secretion systems. Cell Microbiol 2007; 10:958-84. [PMID: 18031307 PMCID: PMC2343689 DOI: 10.1111/j.1462-5822.2007.01099.x] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The biogenesis of the Salmonella-containing vacuole within mammalian cells has been intensively studied over recent years. However, the ability of Salmonella to sense and adapt to the intracellular environment of different types of host cells has received much less attention. To address this issue, we report the transcriptome of Salmonella enterica serovar Typhimurium SL1344 within epithelial cells and show comparisons with Salmonella gene expression inside macrophages. We report that S. Typhimurium expresses a characteristic intracellular transcriptomic signature in response to the environments it encounters within different cell types. The signature involves the upregulation of the mgtBC, pstACS and iro genes for magnesium, phosphate and iron uptake, and Salmonella pathogenicity island 2 (SPI2). Surprisingly, in addition to SPI2, the invasion-associated SPI1 pathogenicity island and the genes involved in flagellar biosynthesis were expressed inside epithelial cells at later stages of the infection, while they were constantly downregulated in macrophage-like cells. To our knowledge, this is the first report of the simultaneous transcription of all three Type Three Secretion Systems (T3SS) within an intracellular Salmonella population. We discovered that S. Typhimurium strain SL1344 was strongly cytotoxic to epithelial cells after 6 h of infection and hypothesize that the time-dependent changes in Salmonella gene expression within epithelial cells reflects the bacterial response to host cells that have been injured by the infection process.
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Affiliation(s)
- I Hautefort
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, UK.
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Månsson LE, Melican K, Boekel J, Sandoval RM, Hautefort I, Tanner GA, Molitoris BA, Richter-Dahlfors A. Real-time studies of the progression of bacterial infections and immediate tissue responses in live animals. Cell Microbiol 2006; 9:413-24. [PMID: 16953802 DOI: 10.1111/j.1462-5822.2006.00799.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
By combining intravital multiphoton microscopy and bacterial genetics we have developed a technique enabling real-time imaging of bacterial proliferation and tissue responses in a live animal. Spatial and temporal control of the infection process was achieved by microinjecting GFP(+)-expressing uropathogenic Escherichia coli (UPEC) into tubules of exteriorized kidneys in live rats. GFP(+) was introduced in the clinical UPEC strain CFT073 as a single-copy chromosomal gene fusion. Within hours, bacterial colonization was accompanied by marked ischaemic effects, perivascular leakage, loss of tubular integrity and localized recruitment of immune cells. The pathophysiology was altered in response to an isogenic bacterial strain lacking the exotoxin haemolysin, revealing the subtle and temporal roles of bacterial virulence factors in vivo. Microdissection and RNA extraction of the injected nephron allowed molecular analysis of prokaryotic and eukaryotic gene expression. The techniques described here can be applied to study the integrated cell communication evoked by a variety of bacterial pathogens, assisting in the design of strategies to combat bacterial infections.
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Affiliation(s)
- Lisa E Månsson
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, S-171 77 Stockholm, Sweden
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Gantois I, Ducatelle R, Pasmans F, Haesebrouck F, Hautefort I, Thompson A, Hinton JC, Van Immerseel F. Butyrate specifically down-regulates salmonella pathogenicity island 1 gene expression. Appl Environ Microbiol 2006; 72:946-9. [PMID: 16391141 PMCID: PMC1352287 DOI: 10.1128/aem.72.1.946-949.2006] [Citation(s) in RCA: 236] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2005] [Accepted: 10/05/2005] [Indexed: 11/20/2022] Open
Abstract
Invasion of intestinal epithelial cells by Salmonella enterica is decreased after exposure to butyric acid. To understand the molecular mechanisms of this phenomenon, a comparative transcriptomic analysis of Salmonella enterica serovar Enteritidis and Salmonella enterica serovar Typhimurium grown in medium supplemented with butyrate was performed. We found that butyrate down-regulated the expression of 19 genes common to both serovars by a factor of twofold or more, and 17 of these genes localized to the Salmonella pathogenicity island 1 (SPI1). These included the SPI1 regulatory genes hilD and invF. Of the remaining two genes, ampH has 91% homology to an Escherichia coli penicillin-binding protein and sopE2 encodes a type III-secreted effector protein associated with invasion but located at a separate site on the chromosome from SPI1.
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Affiliation(s)
- I Gantois
- Department of Pathology, Bacteriology and Avian Diseases, Research Group Veterinary Public Health and Zoonoses, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium.
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Hinton JCD, Hautefort I, Eriksson S, Thompson A, Rhen M. Benefits and pitfalls of using microarrays to monitor bacterial gene expression during infection. Curr Opin Microbiol 2004; 7:277-82. [PMID: 15196496 DOI: 10.1016/j.mib.2004.04.009] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The understanding of bacterial pathogenesis is dependent on techniques that elucidate the underlying genetic and biochemical mechanisms. To study the mechanism of bacterial survival and proliferation within host cells we need accurate tools that tell us what is occurring within the infecting organism. It has now become possible to determine the transcriptional status of in vivo-derived bacteria at the level of the whole genome. Such expression profiles serve as a monitor of the host cell environment as well as an indicator of the bacterial adaptation to its intracellular niche. Here, we review the methods used to produce microarray data for defining the bacterial intracellular transcriptome, and examine the pitfalls in extracting bacterial RNA from the infected host compartment.
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Affiliation(s)
- Jay C D Hinton
- Molecular Microbiology Group, Institute of Food Research, Norwich Research Park, Norwich, NR4 7UA, United Kingdom.
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Hautefort I, Proença MJ, Hinton JCD. Single-copy green fluorescent protein gene fusions allow accurate measurement of Salmonella gene expression in vitro and during infection of mammalian cells. Appl Environ Microbiol 2004; 69:7480-91. [PMID: 14660401 PMCID: PMC310007 DOI: 10.1128/aem.69.12.7480-7491.2003] [Citation(s) in RCA: 194] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
We developed a reliable and flexible green fluorescent protein (GFP)-based system for measuring gene expression in individual bacterial cells. Until now, most systems have relied upon plasmid-borne gfp gene fusions, risking problems associated with plasmid instability. We show that a recently developed GFP variant, GFP+, is suitable for assessing bacterial gene expression. Various gfp+ transcriptional fusions were constructed and integrated as single copies into the chromosome of Salmonella enterica serovar Typhimurium. A comparison of the expression levels of proU-lacZ and proU-gfp+ fusions showed that GFP+ reported proU activity in individual Salmonella cells as accurately as beta-galactosidase reported activity for entire populations. The single-copy gfp+ fusions were ideal for monitoring up- and downregulation of Salmonella virulence genes. We discovered that in vitro induction of the SPI1gene prgH occurs only in a portion of the population and that the proportion varies with the growth phase. We determined the level of expression of the SPI2 gene ssaG in bacteria released from murine macrophages. Our results demonstrate for the first time that single-copy GFP+ fusions reliably report gene expression in simple and complex environments. This approach promises to allow accurate measurement of gene expression in individual bacteria during animal infection.
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Affiliation(s)
- Isabelle Hautefort
- Molecular Microbiology Group, Institute of Food Research, Norwich NR4 7UA, United Kingdom
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Abstract
To date, the majority of studies of bacterial gene expression have been carried out on large communities, as techniques for analysis of expression in individual cells have not been available. Recent developments now allow us to use reporter genes to monitor gene expression in individual bacterial cells. Conventional reporters are not suitable for studies of living single cells. However, variants of GFP have proved to be ideal for the study of development, cell biology, and pathogenesis and are now the reporters of choice for microbial studies. In combination with techniques such as DFI and IVET and the use of flow cytometry and advanced fluorescence microscopy, the latest generation of GFP reporters allows the investigation of gene expression in individual bacterial cells within particular environments. These studies promise to bring a new level of understanding to the fields of bacterial pathogenesis and environmental microbiology.
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Affiliation(s)
- Roy J M Bongaerts
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, United Kingdom
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Abstract
The complexities of bacterial gene expression during mammalian infection cannot be addressed by in vitro experiments. We know that the infected host represents a complex and dynamic environment, which is modified during the infection process, presenting a variety of stimuli to which the pathogen must respond if it is to be successful. This response involves hundreds of ivi (in vivo-induced) genes which have recently been identified in animal and cell culture models using a variety of technologies including in vivo expression technology, differential fluorescence induction, subtractive hybridization and differential display. Proteomic analysis is beginning to be used to identify IVI proteins, and has benefited from the availability of genome sequences for increasing numbers of bacterial pathogens. The patterns of bacterial gene expression during infection remain to be investigated. Are ivi genes expressed in an organ-specific or cell-type-specific fashion? New approaches are required to answer these questions. The uses of the immunologically based in vivo antigen technology system, in situ PCR and DNA microarray analysis are considered. This review considers existing methods for examining bacterial gene expression in vivo, and describes emerging approaches that should further our understanding in the future.
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Affiliation(s)
- I Hautefort
- Institute of Food Research, Norwich Research Park, UK.
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Hautefort I, Flechon B, Degrouard J, Fons M. Adhesion to the digestive mucosa is not sufficient for durable persistence of different Lactobacillus fermentumstrains in the digestive tract of mice. Microbial Ecology in Health & Disease 2000. [DOI: 10.3402/mehd.v12i1.8055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Hautefort I, Roels A, Tailliez P, Ladiré M, Raibaud P, Ducluzeau R, Fons M. Selection of Lactobacillus fermentum strains able to durably colonize the digestive tract of mice harboring a complex human flora. FEMS Microbiol Ecol 1999. [DOI: 10.1111/j.1574-6941.1999.tb00595.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Piard JC, Hautefort I, Fischetti VA, Ehrlich SD, Fons M, Gruss A. Cell wall anchoring of the Streptococcus pyogenes M6 protein in various lactic acid bacteria. J Bacteriol 1997; 179:3068-72. [PMID: 9139932 PMCID: PMC179078 DOI: 10.1128/jb.179.9.3068-3072.1997] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The M6 protein from Streptococcus pyogenes is the best-characterized member of a family of cell envelope-associated proteins. Based on the observation that the C-terminal sorting signals of these proteins can drive cell wall anchoring of heterologous unanchored proteins, we have cloned and expressed the emm6 structural gene for the M6 protein in various lactic acid bacteria (LAB). The emm6 gene was successfully expressed from lactococcal promoters in several Lactococcus lactis strains, an animal-colonizing Lactobacillus fermentum strain, Lactobacillus sake, and Streptococcus salivarius subsp. thermophilus. The M6 protein was efficiently anchored to the cell wall in all strains tested. In lactobacilli, essentially all detectable M6 protein was cell wall associated. These results suggest the feasibility of using the C-terminal anchor moiety of M6 for protein surface display in LAB.
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Affiliation(s)
- J C Piard
- Laboratoire de Génétique Microbienne, Institut de Biotechnologie, INRA, Jouy-en-Josas, France.
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Ramare F, Hautefort I, Verhe F, Raibaud P, Iovanna J. Inactivation of tryptic activity by a human-derived strain of Bacteroides distasonis in the large intestines of gnotobiotic rats and mice. Appl Environ Microbiol 1996; 62:1434-6. [PMID: 8919807 PMCID: PMC167912 DOI: 10.1128/aem.62.4.1434-1436.1996] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Tryptic activity disappeared and trypsin was no longer detected with an antitrypsin antiserum in the large intestines of gnotobiotic rats and mice monoassociated with a human-derived strain of Bacteroides distasonis, whereas tryptic activity was not modified in the small intestines. This function was shown to be strain specific.
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Affiliation(s)
- F Ramare
- Unité d'Ecologie et Physiologie du Système Digestif, Centre de Recherches de Jouy en Josas, France
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