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  • Review Article
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Citrobacter rodentium: infection, inflammation and the microbiota

Key Points

  • The mouse pathogen Citrobacter rodentium is a useful model to investigate important human intestinal diseases, including enteropathogenic Escherichia coli (EPEC) and enterohaemorrhagic E. coli (EHEC) infections, Crohn's disease, ulcerative colitis and colon tumorigenesis.

  • Whole-genome sequencing of multiple pathogenic attaching and effacing (A/E) bacteria has led to the identification of many genes that are involved in pathogenesis, including gene families that encode effector proteins of the type III secretion system (T3SS). The functions of many putative virulence genes have been evaluated in the C. rodentium model, which has improved our understanding of pathogenesis and the corresponding host responses.

  • C. rodentium elicits robust inflammasome-dependent responses in a caspase 1- and caspase 11-dependent manner. Type I interferon signalling is a key factor that regulates inflammasome activation in C. rodentium infection.

  • The intestinal microbiota is crucial for coordinating mucosal immune responses to C. rodentium infection, including the development of IgA+ plasma cells, group 3 innate lymphoid cells (ILC3s; also known as inducible T helper (iTH) cells), TH17 cells and TH22 cells.

  • Defined dietary components, such as vitamin D, vitamin E, selenium, ligands from cruciferous vegetables and polyunsaturated fatty acids (PUFAs), as well as the intestinal microbiota, directly modify mucosal immune responses and epithelial barrier function in response to C. rodentium infection.

  • Future research using the C. rodentium model will focus on quantitative proteomics, metabolomics and four-dimensional (4D) imaging studies to unravel pathogen–host–microbiota interactions in unprecedented detail.

Abstract

Citrobacter rodentium is a mucosal pathogen of mice that shares several pathogenic mechanisms with enteropathogenic Escherichia coli (EPEC) and enterohaemorrhagic E. coli (EHEC), which are two clinically important human gastrointestinal pathogens. Thus, C. rodentium has long been used as a model to understand the molecular basis of EPEC and EHEC infection in vivo. In this Review, we discuss recent studies in which C. rodentium has been used to study mucosal immunology, including the deregulation of intestinal inflammatory responses during bacteria-induced colitis and the role of the intestinal microbiota in mediating resistance to colonization by enteric pathogens. These insights should help to elucidate the roles of mucosal inflammatory responses and the microbiota in the virulence of enteric pathogens.

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Figure 1: The role of Tir signalling pathways in the formation of attaching and effacing lesions.
Figure 2: Mucosal immune responses to Citrobacter rodentium.
Figure 3: The role of the microbiota and nutrition in modulating resistance to Citrobacter rodentium colonization.

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References

  1. Schauer, D. B. & Falkow, S. The eae gene of Citrobacter freundii biotype 4280 is necessary for colonization in transmissible murine colonic hyperplasia. Infect. Immun. 61, 4654–4661 (1993).

    CAS  PubMed  PubMed Central  Google Scholar 

  2. Schauer, D. B. & Falkow, S. Attaching and effacing locus of a Citrobacter freundii biotype that causes transmissible murine colonic hyperplasia. Infect. Immun. 61, 2486–2492 (1993).

    CAS  PubMed  PubMed Central  Google Scholar 

  3. Deng, W., Vallance, B. A., Li, Y., Puente, J. L. & Finlay, B. B. Citrobacter rodentium translocated intimin receptor (Tir) is an essential virulence factor needed for actin condensation, intestinal colonization and colonic hyperplasia in mice. Mol. Microbiol. 48, 95–115 (2003).

    Article  CAS  PubMed  Google Scholar 

  4. Frankel, G. & Phillips, A. D. Attaching effacing Escherichia coli and paradigms of Tir-triggered actin polymerization: getting off the pedestal. Cell. Microbiol. 10, 549–556 (2008).

    Article  CAS  PubMed  Google Scholar 

  5. Frankel, G. et al. Enteropathogenic and enterohaemorrhagic Escherichia coli: more subversive elements. Mol. Microbiol. 30, 911–921 (1998).

    Article  CAS  PubMed  Google Scholar 

  6. Nataro, J. P. & Kaper, J. B. Diarrheagenic Escherichia coli. Clin. Microbiol. Rev. 11, 142–201 (1998).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Petty, N. K. et al. The Citrobacter rodentium genome sequence reveals convergent evolution with human pathogenic Escherichia coli. J. Bacteriol. 192, 525–538 (2010).

    Article  CAS  PubMed  Google Scholar 

  8. Wong, A. R. et al. Enteropathogenic and enterohaemorrhagic Escherichia coli: even more subversive elements. Mol. Microbiol. 80, 1420–1438 (2011).

    Article  CAS  PubMed  Google Scholar 

  9. Mundy, R. et al. Identification of a novel Citrobacter rodentium type III secreted protein, EspI, and roles of this and other secreted proteins in infection. Infect. Immun. 72, 2288–2302 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Arbeloa, A. et al. Distribution of espM and espT among enteropathogenic and enterohaemorrhagic Escherichia coli. J. Med. Microbiol. 58, 988–995 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Mundy, R. et al. Identification of a novel type IV pilus gene cluster required for gastrointestinal colonization of Citrobacter rodentium. Mol Microbiol 48, 795–809 (2003).

    Article  CAS  PubMed  Google Scholar 

  12. Mallick, E. M. et al. A novel murine infection model for Shiga toxin-producing Escherichia coli. J. Clin. Invest. 122, 4012–4024 (2012). This article describes the generation of a C. rodentium strain that produces Stx, which can be used as a more realistic model of EHEC infection.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Chandrakesan, P. et al. Utility of a bacterial infection model to study epithelial–mesenchymal transition, mesenchymal–epithelial transition or tumorigenesis. Oncogene 33, 2639–2654 (2013).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  14. Higgins, L. M., Frankel, G., Douce, G., Dougan, G. & MacDonald, T. T. Citrobacter rodentium infection in mice elicits a mucosal TH1 cytokine response and lesions similar to those in murine inflammatory bowel disease. Infection Immun. 67, 3031–3039 (1999).

    CAS  Google Scholar 

  15. Mundy, R., MacDonald, T. T., Dougan, G., Frankel, G. & Wiles, S. Citrobacter rodentium of mice and man. Cell. Microbiol. 7, 1697–1706 (2005).

    Article  CAS  PubMed  Google Scholar 

  16. Lupp, C. et al. Host-mediated inflammation disrupts the intestinal microbiota and promotes the overgrowth of Enterobacteriaceae. Cell Host Microbe 2, 204 (2007).

    Article  CAS  PubMed  Google Scholar 

  17. Hoffmann, C. et al. Community-wide response of the gut microbiota to enteropathogenic Citrobacter rodentium infection revealed by deep sequencing. Infect. Immun. 77, 4668–4678 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Clare, S. et al. Enhanced susceptibility to Citrobacter rodentium infection in microRNA-155-deficient mice. Infect. Immun. 81, 723–732 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Wiles, S. et al. Organ specificity, colonization and clearance dynamics in vivo following oral challenges with the murine pathogen Citrobacter rodentium. Cell. Microbiol. 6, 963–972 (2004). This study uses bioluminescence imaging to characterize the C. rodentium infection cycle in mice.

    Article  CAS  PubMed  Google Scholar 

  20. Papapietro, O. et al. R-spondin 2 signalling mediates susceptibility to fatal infectious diarrhoea. Nature Commun. 4, 1898 (2013). This study was the first to identify the molecular basis of genetic susceptibility to C. rodentium infection.

    Article  CAS  Google Scholar 

  21. Borenshtein, D., McBee, M. E. & Schauer, D. B. Utility of the Citrobacter rodentium infection model in laboratory mice. Curr. Opin. Gastroenterol. 24, 32–37 (2008).

    Article  PubMed  Google Scholar 

  22. Borenshtein, D., Nambiar, P. R., Groff, E. B., Fox, J. G. & Schauer, D. B. Development of fatal colitis in FVB mice infected with Citrobacter rodentium. Infect. Immun. 75, 3271–3281 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Willing, B. P., Vacharaksa, A., Croxen, M., Thanachayanont, T. & Finlay, B. B. Altering host resistance to infections through microbial transplantation. PLoS ONE 6, e26988 (2011). This study shows that increased IL-22 production by the intestinal microbiota is associated with host resistance to C. rodentium infection.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Ivanov, I. I. et al. Induction of intestinal TH17 cells by segmented filamentous bacteria. Cell 139, 485–498 (2009). This study shows that SFB of the microbiota can stimulate CD4+ T helper cells to release IL-17 and IL-22, which results in resistance to C. rodentium infection.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Ghosh, S. et al. Colonic microbiota alters host susceptibility to infectious colitis by modulating inflammation, redox status, and ion transporter gene expression. Am. J. Physiol. Gastrointest. Liver Physiol. 301, G39–G49 (2011).

    Article  CAS  PubMed  Google Scholar 

  26. Borenshtein, D. et al. Decreased expression of colonic Slc26a3 and carbonic anhydrase iv as a cause of fatal infectious diarrhea in mice. Infect. Immun. 77, 3639–3650 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Wiles, S., Pickard, K. M., Peng, K., MacDonald, T. T. & Frankel, G. In vivo bioluminescence imaging of the murine pathogen Citrobacter rodentium. Infect. Immun. 74, 5391–5396 (2006).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Luperchio, S. A. & Schauer, D. B. Molecular pathogenesis of Citrobacter rodentium and transmissible murine colonic hyperplasia. Microbes Infect. 3, 333–340 (2001).

    Article  CAS  PubMed  Google Scholar 

  29. Collins, J. W., Meganck, J., Kuo, C., Francis, K. P. & Frankel, G. 4D multimodality imaging of Citrobacter rodentium infections in mice. J. Vis. Exp. http://dx.doi.org/10.3791/50450 (2013).

  30. Wiles, S., Dougan, G. & Frankel, G. Emergence of a 'hyperinfectious' bacterial state after passage of Citrobacter rodentium through the host gastrointestinal tract. Cell. Microbiol. 7, 1163–1172 (2005).

    Article  CAS  PubMed  Google Scholar 

  31. Wickham, M. E., Brown, N. F., Boyle, E. C., Coombes, B. K. & Finlay, B. B. Virulence is positively selected by transmission success between mammalian hosts. Curr. Biol. 17, 783–788 (2007).

    Article  CAS  PubMed  Google Scholar 

  32. Bishop, A. L., Wiles, S., Dougan, G. & Frankel, G. Cell attachment properties and infectivity of host-adapted and environmentally adapted Citrobacter rodentium. Microbes Infect. 9, 1316–1324 (2007).

    Article  CAS  PubMed  Google Scholar 

  33. Deng, W., Li, Y., Vallance, B. A. & Finlay, B. B. Locus of enterocyte effacement from Citrobacter rodentium: sequence analysis and evidence for horizontal transfer among attaching and effacing pathogens. Infect. Immun. 69, 6323–6335 (2001).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Deng, W. et al. Dissecting virulence: systematic and functional anlyses of a pathogenicity island. Proc. Natl Acad. Sci. USA 101, 3597–3602 (2004).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Lai, Y., Rosenshine, I., Leong, J. M. & Frankel, G. Intimate host attachment: enteropathogenic and enterohaemorrhagic Escherichia coli. Cell Microbiol. 15, 1796–1808 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  36. Crepin, V. F. et al. Dissecting the role of the Tir:Nck and Tir:IRTKS/IRSp53 signalling pathways in vivo. Mol. Microbiol. 75, 308–323 (2010). This study shows that the Tir signalling pathways that are triggered in cultured epithelial cells in vitro by EPEC, EHEC and C. rodentium are not required for A/E lesion formation in vivo.

    Article  CAS  PubMed  Google Scholar 

  37. Kelly, M. et al. Essential role of the type III secretion system effector NleB in colonization of mice by Citrobacter rodentium. Infect. Immun. 74, 2328–2337 (2006).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Guttman, J. A., Samji, F. N., Li, Y., Vogl, A. W. & Finlay, B. B. Evidence that tight junctions are disrupted due to intimate bacterial contact and not inflammation during attaching and effacing pathogen infection in vivo. Infect. Immun. 74, 6075–6084 (2006).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  39. Guttman, J. A. et al. Attaching and effacing pathogen-induced tight junction disruption in vivo. Cell. Microbiol. 8, 634–645 (2006).

    Article  CAS  PubMed  Google Scholar 

  40. Hemrajani, C. et al. NleH effectors interact with Bax inhibitor-1 to block apoptosis during enteropathogenic Escherichia coli infection. Proc. Natl Acad. Sci. USA 107, 3129–3134 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  41. Selyunin, A. S., Reddick, L. E., Weigele, B. A. & Alto, N. M. Selective protection of an ARF1–GTP signaling axis by a bacterial scaffold induces bidirectional trafficking arrest. Cell Rep. 6, 878–891 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Marches, O. et al. EspJ of enteropathogenic and enterohaemorrhagic Escherichia coli inhibits opsono-phagocytosis. Cell. Microbiol. 10, 1104–1115 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Sham, H. P. et al. Attaching and effacing bacterial effector NleC suppresses epithelial inflammatory responses by inhibiting NF-кB and p38 mitogen-activated protein kinase activation. Infect. Immun. 79, 3552–3562 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  44. Kim, M. et al. Bacterial interactions with the host epithelium. Cell Host Microbe 8, 20–35 (2010).

    Article  CAS  PubMed  Google Scholar 

  45. Kamada, N. et al. Regulated virulence controls the ability of a pathogen to compete with the gut microbiota. Science 336, 1325–1329 (2012). This study suggests that temporal expression of the virulence factor Ler controls the ability of C. rodentium to outcompete the gut microbiota.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  46. Gruenheid, S. et al. Identification and characterization of NleA, a non-LEE-encoded type III translocated virulence factor of enterohaemorrhagic Escherichia coli O157:H7. Mol. Microbiol. 51, 1233–1249 (2004).

    Article  CAS  PubMed  Google Scholar 

  47. Hart, E. et al. RegA, an AraC-like protein, is a global transcriptional regulator that controls virulence gene expression in Citrobacter rodentium. Infect. Immun. 76, 5247–5256 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  48. Gueguen, E. & Cascales, E. Promoter swapping unveils the role of the Citrobacter rodentium CTS1 type VI secretion system in interbacterial competition. Appl. Environ. Microbiol. 79, 32–38 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  49. Yang, J., Tauschek, M., Hart, E., Hartland, E. L. & Robins-Browne, R. M. Virulence regulation in Citrobacter rodentium: the art of timing. Microb. Biotechnol. 3, 259–268 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  50. Rutherford, S. T. & Bassler, B. L. Bacterial quorum sensing: its role in virulence and possibilities for its control. Cold Spring Harb. Perspect. Med. 2, a012427 (2012).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  51. Coulthurst, S. J. et al. Quorum sensing has an unexpected role in virulence in the model pathogen Citrobacter rodentium. EMBO Rep. 8, 698–703 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  52. Lawhon, S. D., Maurer, R., Suyemoto, M. & Altier, C. Intestinal short-chain fatty acids alter Salmonella Typhimurium invasion gene expression and virulence through BarA/SirA. Mol. Microbiol. 46, 1451–1464 (2002).

    Article  CAS  PubMed  Google Scholar 

  53. Kawai, T. & Akira, S. Toll-like receptor and RIG-I-like receptor signaling. Ann. NY Acad. Sci. 1143, 1–20 (2008).

    Article  CAS  PubMed  Google Scholar 

  54. Gibson, D. et al. MyD88 signalling plays a critical role in host defence by controlling pathogen burden and promoting epithelial cell homeostasis during Citrobacter rodentium-induced colitis. Cell. Microbiol. 10, 618–631 (2008).

    Article  CAS  PubMed  Google Scholar 

  55. Lebeis, S. L., Bommarius, B., Parkos, C. A., Sherman, M. A. & Kalman, D. TLR signaling mediated by MyD88 is required for a protective innate immune response by neutrophils to Citrobacter rodentium. J. Immunol. 179, 566–577 (2007).

    Article  CAS  PubMed  Google Scholar 

  56. Bergstrom, K. S., Sham, H. P., Zarepour, M. & Vallance, B. A. Innate host responses to enteric bacterial pathogens: a balancing act between resistance and tolerance. Cell. Microbiol. 14, 475–484 (2012).

    Article  CAS  PubMed  Google Scholar 

  57. Gibson, D. L. et al. Toll-like receptor 2 plays a critical role in maintaining mucosal integrity during Citrobacter rodentium-induced colitis. Cell. Microbiol. 10, 388–403 (2008).

    Article  CAS  PubMed  Google Scholar 

  58. Khan, M. A. et al. Toll-like receptor 4 contributes to colitis development but not to host defense during Citrobacter rodentium infection in mice. Infection Immun. 74, 2522–2536 (2006).

    Article  CAS  Google Scholar 

  59. Geddes, K. et al. Identification of an innate T helper type 17 response to intestinal bacterial pathogens. Nature Med. 17, 837–844 (2011).

    Article  CAS  PubMed  Google Scholar 

  60. Zaki, M. H., Lamkanfi, M. & Kanneganti, T.-D. The Nlrp3 inflammasome: contributions to intestinal homeostasis. Trends Immunol. 32, 171–179 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  61. Franchi, L., Eigenbrod, T., Munoz-Planillo, R. & Nunez, G. The inflammasome: a caspase-1-activation platform that regulates immune responses and disease pathogenesis. Nature Immunol. 10, 241–247 (2009).

    Article  CAS  Google Scholar 

  62. Rathinam, V. A., Vanaja, S. K. & Fitzgerald, K. A. Regulation of inflammasome signaling. Nature Immunol. 13, 333–332 (2012).

    Article  CAS  Google Scholar 

  63. Kayagaki, N. et al. Non-canonical inflammasome activation targets caspase-11. Nature 479, 117–121 (2011). This study describes an essential role for caspase 11 in driving IL-1 responses against C. rodentium.

    Article  CAS  PubMed  Google Scholar 

  64. Gurung, P. et al. Toll or interleukin-1 receptor (TIR) domain-containing adaptor inducing interferon-β (TRIF)-mediated caspase-11 protease production integrates Toll-like receptor 4 (TLR4) protein-and Nlrp3 inflammasome-mediated host defense against enteropathogens. J. Biol. Chem. 287, 34474–34483 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  65. Broz, P. et al. Caspase-11 increases susceptibility to Salmonella infection in the absence of caspase-1. Nature 490, 288–291 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  66. Rathinam, V. A. et al. TRIF licenses caspase-11-dependent NLRP3 inflammasome activation by Gram-negative bacteria. Cell 150, 606–619 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  67. Kayagaki, N. et al. Noncanonical inflammasome activation by intracellular LPS independent of TLR4. Science 341, 1246–1249 (2013).

    Article  CAS  PubMed  Google Scholar 

  68. Liu, Z. et al. Role of inflammasomes in host defense against Citrobacter rodentium infection. J. Biol. Chem. 287, 16955–16964 (2012). References 66, 67 and 68 show that the TRIF–type I IFN axis is essential for inflammasome-mediated responses to C. rodentium.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  69. Khan, M. A. et al. Flagellin-dependent and -independent inflammatory responses following infection by enteropathogenic Escherichia coli and Citrobacter rodentium. Infect. Immun. 76, 1410–1422 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  70. Simmons, C. P. et al. Central role for B lymphocytes and CD4+ T cells in immunity to infection by the attaching and effacing pathogen Citrobacter rodentium. Infection Immun. 71, 5077–5086 (2003).

    Article  CAS  Google Scholar 

  71. Vallance, B. A., Deng, W., Knodler, L. A. & Finlay, B. B. Mice lacking T and B lymphocytes develop transient colitis and crypt hyperplasia yet suffer impaired bacterial clearance during Citrobacter rodentium infection. Infection Immun. 70, 2070–2081 (2002).

    Article  CAS  Google Scholar 

  72. Simmons, C. P. et al. Impaired resistance and enhanced pathology during infection with a noninvasive, attaching-effacing enteric bacterial pathogen, Citrobacter rodentium, in mice lacking IL-12 or IFN-γ. J. Immunol. 168, 1804–1812 (2002).

    Article  CAS  PubMed  Google Scholar 

  73. Shiomi, H. et al. Gamma interferon produced by antigen-specific CD4+ T cells regulates the mucosal immune responses to Citrobacter rodentium infection. Infection Immun. 78, 2653–2666 (2010).

    Article  CAS  Google Scholar 

  74. O'Quinn, D. B., Palmer, M. T., Lee, Y. K. & Weaver, C. T. Emergence of the TH17 pathway and its role in host defense. Adv. Immunol. 99, 115–163 (2008).

    Article  CAS  PubMed  Google Scholar 

  75. Spits, H. et al. Innate lymphoid cells — a proposal for uniform nomenclature. Nature Rev. Immunol. 13, 145–149 (2013).

    Article  CAS  Google Scholar 

  76. Mangan, P. R. et al. Transforming growth factor-β induces development of the TH17 lineage. Nature 441, 231–234 (2006).

    Article  CAS  PubMed  Google Scholar 

  77. Torchinsky, M. B., Garaude, J., Martin, A. P. & Blander, J. M. Innate immune recognition of infected apoptotic cells directs TH17 cell differentiation. Nature 458, 78–82 (2009).

    Article  CAS  PubMed  Google Scholar 

  78. Lawley, T. D. et al. Targeted restoration of the intestinal microbiota with a simple, defined bacteriotherapy resolves relapsing Clostridium difficile disease in mice. PLoS Pathog. 8, e1002995 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  79. Fritz, J. H. et al. Acquisition of a multifunctional IgA+ plasma cell phenotype in the gut. Nature 481, 199–203 (2012).

    Article  CAS  Google Scholar 

  80. Rodrigues, D. M., Sousa, A. J., Johnson-Henry, K. C., Sherman, P. M. & Gareau, M. G. Probiotics are effective for the prevention and treatment of Citrobacter rodentium-induced colitis in mice. J. Infect. Dis. 206, 99–109 (2012).

    Article  CAS  PubMed  Google Scholar 

  81. Fanning, S. et al. Bifidobacterial surface-exopolysaccharide facilitates commensal–host interaction through immune modulation and pathogen protection. Proc. Natl Acad. Sci. USA 109, 2108–2113 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  82. Collins, J. W. et al. Fermented dairy products modulate C. rodentium induced colonic hyperplasia. J. Infect. Dis. http://dx.doi.org/10.1093/infdis/jiu205 (2014).

  83. Zenewicz, L. A. et al. IL-22 deficiency alters colonic microbiota to be transmissible and colitogenic. J. Immunol. 190, 5306–5312 (2013).

    Article  CAS  PubMed  Google Scholar 

  84. Kiss, E. A. et al. Natural aryl hydrocarbon receptor ligands control organogenesis of intestinal lymphoid follicles. Science 334, 1561–1565 (2011).

    Article  CAS  PubMed  Google Scholar 

  85. Ryz, N. R. et al. Active vitamin D (1,25-dihydroxyvitamin D3) increases host susceptibility to Citrobacter rodentium by suppressing mucosal TH17 responses. Am. J. Physiol. Gastrointest. Liver Physiol. 303, G1299–G1311 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  86. Smith, A. D., Botero, S., Shea-Donohue, T. & Urban, J. F. Jr. The pathogenicity of an enteric Citrobacter rodentium infection is enhanced by deficiencies in the antioxidants selenium and vitamin E. Infect. Immun. 79, 1471–1478 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  87. Ghosh, S. et al. Fish oil attenuates omega-6 polyunsaturated fatty acid-induced dysbiosis and infectious colitis but impairs LPS dephosphorylation activity causing sepsis. PLoS ONE 8, e55468 (2013). This study shows that polyunsaturated fatty acids (omega-3 PUFA and omega-6 PUFA) modulate C. rodentium translocation and mortality in mice.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  88. Duck, L. W. et al. Isolation of flagellated bacteria implicated in Crohn's disease. Inflamm. Bowel Dis. 13, 1191–1201 (2007).

    Article  PubMed  Google Scholar 

  89. Mondot, S. et al. Highlighting new phylogenetic specificities of Crohn's disease microbiota. Inflamm. Bowel Dis. 17, 185–192 (2011).

    Article  CAS  PubMed  Google Scholar 

  90. Monteleone, I., Pallone, F. & Monteleone, G. TH17-related cytokines: new players in the control of chronic intestinal inflammation. BMC Med. 9, 122 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  91. Sekirov, I. et al. Antibiotic-induced perturbations of the intestinal microbiota alter host susceptibility to enteric infection. Infect. Immun. 76, 4726–4736 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  92. Bergstrom, K. S. et al. Muc2 protects against lethal infectious colitis by disassociating pathogenic and commensal bacteria from the colonic mucosa. PLoS Pathog. 6, e1000902 (2010).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  93. Wlodarska, M. et al. Antibiotic treatment alters the colonic mucus layer and predisposes the host to exacerbated Citrobacter rodentium-induced colitis. Infect. Immun. 79, 1536–1545 (2011). This study shows that metronidazole treatment alters the microbiota and supresses goblet cell function, thereby enhancing C. rodentium colonization.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  94. Burger-van Paassen, N. et al. The regulation of intestinal mucin MUC2 expression by short-chain fatty acids: implications for epithelial protection. Biochem. J. 420, 211–219 (2009).

    Article  CAS  PubMed  Google Scholar 

  95. Wlodarska, M. et al. NLRP6 inflammasome orchestrates the colonic host–microbial interface by regulating goblet cell mucus secretion. Cell 156, 1045–1059 (2014). This study is the first to demonstrate that innate immune signalling pathways modulate goblet cell function and defence against C. rodentium infection.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  96. Croxen, M. A. & Finlay, B. B. Molecular mechanisms of Escherichia coli pathogenicity. Nature Rev. Microbiol. 8, 26–38 (2010).

    Article  CAS  Google Scholar 

  97. Raymond, B. et al. Subversion of trafficking, apoptosis, and innate immunity by type III secretion system effectors. Trends Microbiol. 21, 430–441 (2013).

    Article  CAS  PubMed  Google Scholar 

  98. Law, R. J., Gur-Arie, L., Rosenshine, I. & Finlay, B. B. In vitro and in vivo model systems for studying enteropathogenic Escherichia coli infections. Cold Spring Harb. Perspect. Med. 3, a009977 (2013).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  99. Basu, R. et al. TH22 cells are an important source of IL-22 for host protection against enteropathogenic bacteria. Immunity 37, 1061–1075 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  100. Gibson, D. L. et al. Interleukin-11 reduces TLR4-induced colitis in TLR2-deficient mice and restores intestinal STAT3 signaling. Gastroenterology 139, 1277–1288 (2010).

    Article  CAS  PubMed  Google Scholar 

  101. Ota, N. et al. IL-22 bridges the lymphotoxin pathway with the maintenance of colonic lymphoid structures during infection with Citrobacter rodentium. Nature Immunol. 12, 941–948 (2011).

    Article  CAS  Google Scholar 

  102. Tumanov, A. V. et al. Lymphotoxin controls the IL-22 protection pathway in gut innate lymphoid cells during mucosal pathogen challenge. Cell Host Microbe 10, 44–53 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  103. Kim, M. H., Kang, S. G., Park, J. H., Yanagisawa, M. & Kim, C. H. Short-chain fatty acids activate GPR41 and GPR43 on intestinal epithelial cells to promote inflammatory responses in mice. Gastroenterology 145, 396–406 (2013).

    Article  CAS  PubMed  Google Scholar 

  104. Weinstock, G. M. Genomic approaches to studying the human microbiota. Nature 489, 250–256 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  105. Pham, T. A. & Lawley, T. D. Emerging insights on intestinal dysbiosis during bacterial infections. Curr. Opin. Microbiol. 17, 67–74 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  106. Winter, S. E. et al. Gut inflammation provides a respiratory electron acceptor for Salmonella. Nature 467, 426–429 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  107. Spees, A. M. et al. Streptomycin-induced inflammation enhances Escherichia coli gut colonization through nitrate respiration. mBio 4, e00430–13 (2013).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  108. Barker, N., van de Wetering, M. & Clevers, H. The intestinal stem cell. Genes Dev. 22, 1856–1864 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  109. Diez, E. et al. Identification and characterization of Cri1, a locus controlling mortality during Citrobacter rodentium infection in mice. Genes Immun. 12, 280–290 (2011).

    Article  CAS  PubMed  Google Scholar 

  110. Chandrakesan, P. et al. Novel changes in NF-кB activity during progression and regression phases of hyperplasia: role of MEK, ERK, and p38. J. Biol. Chem. 285, 33485–33498 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  111. Higgins, L. M. et al. Role of bacterial intimin in colonic hyperplasia and inflammation. Science 285, 588–591 (1999).

    Article  CAS  PubMed  Google Scholar 

  112. Brown, J. B. et al. Epithelial phosphatidylinositol-3-kinase signaling is required for β-catenin activation and host defense against Citrobacter rodentium infection. Infect. Immun. 79, 1863–1872 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  113. Zheng, Y. et al. Interleukin-22 mediates early host defense against attaching and effacing bacterial pathogens. Nature Med. 14, 282–289 (2008).

    Article  CAS  PubMed  Google Scholar 

  114. Deng, W. et al. A comprehensive proteomic analysis of the type III secretome of Citrobacter rodentium. J. Biol. Chem. 285, 6790–6800 (2010).

    Article  CAS  PubMed  Google Scholar 

  115. Hardwidge, P. R. et al. Proteomic analysis of the intestinal epithelial cell response to enteropathogenic Escherichia coli. J. Biol. Chem. 279, 20127–20136 (2004).

    Article  CAS  PubMed  Google Scholar 

  116. Hartland, E. L. et al. Binding of intimin from enteropathogenic Escherichia coli to Tir and to host cells. Mol. Microbiol. 32, 151–158 (1999).

    Article  CAS  PubMed  Google Scholar 

  117. Kenny, B. Phosphorylation of tyrosine 474 of the enteropathogenic Escherichia coli (EPEC) Tir receptor molecule is essential for actin nucleating activity and is preceded by additional host modifications. Mol. Microbiol. 31, 1229–1241 (1999).

    Article  CAS  PubMed  Google Scholar 

  118. Gruenheid, S. et al. Enteropathogenic E. coli Tir binds Nck to initiate actin pedestal formation in host cells. Nature Cell Biol. 3, 856–859 (2001).

    Article  CAS  PubMed  Google Scholar 

  119. Wong, A. R., Raymond, B., Collins, J. W., Crepin, V. F. & Frankel, G. The enteropathogenic E. coli effector EspH promotes actin pedestal formation and elongation via WASP-interacting protein (WIP). Cell. Microbiol. 14, 1051–1070 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  120. Campellone, K. G. & Leong, J. M. Nck-independent actin assembly is mediated by two phosphorylated tyrosines within enteropathogenic Escherichia coli Tir. Mol. Microbiol. 56, 416–432 (2005).

    Article  CAS  PubMed  Google Scholar 

  121. Brady, M. J., Campellone, K. G., Ghildiyal, M. & Leong, J. M. Enterohaemorrhagic and enteropathogenic Escherichia coli Tir proteins trigger a common Nck-independent actin assembly pathway. Cell. Microbiol. 9, 2242–2253 (2007).

    Article  CAS  PubMed  Google Scholar 

  122. Vingadassalom, D. et al. Insulin receptor tyrosine kinase substrate links the E. coli O157:H7 actin assembly effectors Tir and EspF(U) during pedestal formation. Proc. Natl Acad. Sci. USA 106, 6754–6759 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  123. Weiss, S. M. et al. IRSp53 links the enterohemorrhagic E. coli effectors Tir and EspFU for actin pedestal formation. Cell Host Microbe 5, 244–258 (2009).

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

The authors are supported by the Canadian Institutes for Health (CIHR) operating grants (to K.M.K. and B.B.F.), US National Institutes of Health (NIH) grant AI083713 (to K.A.F.), NIH grant AI085761 (to K.M.K.), the Wellcome Trust and the UK Medical Research Council (MRC) (to G.F.).

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Crohn's disease

A chronic inflammatory disease of the gastrointestinal tract; it primarily affects the ileum and colon and causes recurrent abdominal pain, fatigue, weight loss, blood and mucus in the faeces, and diarrhoea.

Ulcerative colitis

A chronic inflammatory disease of the colon and rectum that is characterized by recurrent abdominal pain, chills, fever, colitis and diarrhoea.

Sterilizing immunity

An immune response that completely prevents an infection.

Coprophagy

The consumption of faeces.

H-NS family

(Histone-like nucleoid-structuring family). A family of DNA-binding proteins that bind to AT-rich double-stranded DNA and are involved in transcriptional silencing and bacterial chromosome organization.

Integration host factor

(IHF). A histone-like DNA-binding protein that binds to consensus sites and bends the DNA to form a nucleoprotein complex that promotes transcription.

AHL-type quorum sensing system

(N-Acyl-homoserine lactone quorum sensing system). A dedicated communication system that is present in Gram-negative bacteria and is used to regulate specific genes in response to population density via the production of autoinducer 1.

LuxS quorum sensing system

A communication system that is found in both Gram-positive and Gram-negative bacteria; it controls the expression of virulence genes in a cell density-dependent manner via the production of the signalling molecule autoinducer 2 by luxS.

C3H/HeJ mice

A substrain of the widely used laboratory mouse strain C3H; they carry a mutation in Tlr4 and are resistant to endotoxin exposure.

BarA–SirA two-component regulatory system

A two-component system that is present in Salmonella enterica subsp. enterica serovar Typhimurium. BarA encodes a histidine kinase and SirA encodes the response regulator. Following activation, the system triggers a signalling cascade that results in increased expression of virulence genes and decreased expression of motility genes.

iNOS

(Inducible nitric oxide synthase). A cytosolic enzyme that is found in multiple cell types and that produces nitrous oxide (NO) from L-arginine, following induction by lipopolysaccharide and pro-inflammatory cytokines. It is presumed that the production of NO, in conjunction with superoxide radicals, leads to the formation of antimicrobial reactive nitrogen intermediates, such as peroxynitrite and nitrosothiols, which restrict the growth of invading pathogens.

Inflammasomes

Macromolecular complexes that are found in the cytosol of haematopoietic cells and are assembled in response to a range of microbial and endogenous danger signals, which leads to the proteolytic activation of the effector protein caspase 1. Inflammasomes typically consist of a receptor, an adaptor molecule (apoptosis-associated speck-like protein containing caspase activation and recruitment domain), and the effector caspase 1.

Specific pathogen-free mice

Mice that are provided by laboratory animal vendors or are generated in a home laboratory, that have a guaranteed health status and are free of particular pathogens.

Faecal microbiota transplantation

(FMT). A transplantation process in which the faecal material (including the faecal microbiota) from a healthy donor is transferred into a recipient. Patients are often treated by enema infusion or the consumption of capsules containing donor faeces.

Intestinal lymphoid follicles

A type of lymphoid tissue that consists of aggregates of B cells, CD4+ T cells and IgA-producing plasma cells, which are found directly underneath the associated epithelium. These follicles are induced following environmental cues from the intestinal microbiota and dietary components.

RegIII antimicrobial peptides

Secreted antimicrobial peptides that are produced in the gastrointestinal tract and pancreas and consist of a signal peptide and a single C-type lectin domain; they bind to peptidoglycan and are bactericidal for Gram-positive bacteria.

Trefoil factor

A secretory protein that contains a trefoil motif and is produced by goblet cells in the gastrointestinal mucosa; it is thought to protect against mucosal damage by stabilizing the mucus layer.

Resistin-like molecule B

A protein that is produced by intestinal goblet cells and is induced by microorganisms; it is thought to regulate innate mucosal immune responses, such as macrophage activation and antimicrobial lectin expression.

Altered Schaedler flora

(ASF). A cocktail of eight culturable bacterial strains that is used to colonize the gastrointestinal tract of germ-free mice, thereby generating a defined low-complexity microbiota. Notably, different variations of ASF are commercially available.

Monocolonized mice

Former germ-free mice that have been colonized with a single bacterial strain.

Humanized microbiota

A term used to describe human microbiota colonizing the mouse gastrointestinal tract.

Metabolome

The complete profile of small-molecule metabolites, such as amino acids, nucleotides, antioxidants, organic acids, vitamins, hormones, drugs and food components that are found within a cell, tissue, organ or entire organism.

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Collins, J., Keeney, K., Crepin, V. et al. Citrobacter rodentium: infection, inflammation and the microbiota. Nat Rev Microbiol 12, 612–623 (2014). https://doi.org/10.1038/nrmicro3315

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