Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Enteric defensins are essential regulators of intestinal microbial ecology

Abstract

Antimicrobial peptides are important effectors of innate immunity throughout the plant and animal kingdoms. In the mammalian small intestine, Paneth cell α-defensins are antimicrobial peptides that contribute to host defense against enteric pathogens. To determine if α-defensins also govern intestinal microbial ecology, we analyzed the intestinal microbiota of mice expressing a human α-defensin gene (DEFA5) and in mice lacking an enzyme required for the processing of mouse α-defensins. In these complementary models, we detected significant α-defensin-dependent changes in microbiota composition, but not in total bacterial numbers. Furthermore, DEFA5-expressing mice had striking losses of segmented filamentous bacteria and fewer interleukin 17 (IL-17)-producing lamina propria T cells. Our data ascribe a new homeostatic role to α-defensins in regulating the makeup of the commensal microbiota.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Expression of Paneth cell effector genes in Mmp7−/−, DEFA5-transgenic (+/+) and wild-type mice.
Figure 2: Community comparisons and phylogenetic analysis of bacterial composition of the distal small intestine.
Figure 3: Quantitative analysis of intestinal bacterial groups.
Figure 4: FISH of adherent bacteria in mouse distal small intestine.
Figure 5: Influence of maternal exposure on SFB colonization in mouse distal small intestine.
Figure 6: Quantitative comparison of total bacteria by intestinal segment.
Figure 7: TH17 profile of LPLs from the distal small intestine.

Similar content being viewed by others

References

  1. O'Hara, A.M. & Shanahan, F. The gut flora as a forgotten organ. EMBO Rep. 7, 688–693 (2006).

    Article  CAS  Google Scholar 

  2. Stecher, B. & Hardt, W.D. The role of microbiota in infectious disease. Trends Microbiol. 16, 107–114 (2008).

    Article  CAS  Google Scholar 

  3. Macpherson, A.J. & Harris, N.L. Interactions between commensal intestinal bacteria and the immune system. Nat. Rev. Immunol. 4, 478–485 (2004).

    Article  CAS  Google Scholar 

  4. Round, J.L. & Mazmanian, S.K. The gut microbiota shapes intestinal immune responses during health and disease. Nat. Rev. Immunol. 9, 313–323 (2009).

    Article  CAS  Google Scholar 

  5. Gill, S.R. et al. Metagenomic analysis of the human distal gut microbiome. Science 312, 1355–1359 (2006).

    Article  CAS  Google Scholar 

  6. Eckburg, P.B. et al. Diversity of the human intestinal microbial flora. Science 308, 1635–1638 (2005).

    Article  Google Scholar 

  7. Ley, R.E., Lozupone, C.A., Hamady, M., Knight, R. & Gordon, J.I. Worlds within worlds: evolution of the vertebrate gut microbiota. Nat. Rev. Microbiol. 6, 776–788 (2008).

    Article  CAS  Google Scholar 

  8. Rawls, J.F., Mahowald, M.A., Ley, R.E. & Gordon, J.I. Reciprocal gut microbiota transplants from zebrafish and mice to germ-free recipients reveal host habitat selection. Cell 127, 423–433 (2006).

    Article  CAS  Google Scholar 

  9. Ley, R.E. et al. Obesity alters gut microbial ecology. Proc. Natl. Acad. Sci. USA 102, 11070–11075 (2005).

    Article  CAS  Google Scholar 

  10. Ryu, J.H. et al. Innate immune homeostasis by the homeobox gene caudal and commensal-gut mutualism in Drosophila. Science 319, 777–782 (2008).

    Article  CAS  Google Scholar 

  11. Nieuwenhuis, E.E. et al. Cd1d-dependent regulation of bacterial colonization in the intestine of mice. J. Clin. Invest. 119, 1241–1250 (2009).

    Article  CAS  Google Scholar 

  12. Garrett, W.S. et al. Communicable ulcerative colitis induced by T-bet deficiency in the innate immune system. Cell [see comment] 131, 33–45 (2007).

    Article  CAS  Google Scholar 

  13. Suzuki, K. et al. Aberrant expansion of segmented filamentous bacteria in IgA-deficient gut. Proc. Natl. Acad. Sci. USA 101, 1981–1986 (2004).

    Article  CAS  Google Scholar 

  14. Zasloff, M. Antimicrobial peptides of multicellular organisms. Nature 415, 389–395 (2002).

    Article  CAS  Google Scholar 

  15. Selsted, M.E. & Ouellette, A.J. Mammalian defensins in the antimicrobial immune response. Nat. Immunol. 6, 551–557 (2005).

    Article  CAS  Google Scholar 

  16. Porter, E.M., Bevins, C.L., Ghosh, D. & Ganz, T. The multifaceted Paneth cell. Cell. Mol. Life Sci. 59, 156–170 (2002).

    Article  CAS  Google Scholar 

  17. Wilson, C.L. et al. Regulation of intestinal α-defensin activation by the metalloproteinase matrilysin in innate host defense. Science 286, 113–117 (1999).

    Article  CAS  Google Scholar 

  18. Salzman, N.H., Ghosh, D., Huttner, K.M., Paterson, Y. & Bevins, C.L. Protection against enteric salmonellosis in transgenic mice expressing a human intestinal defensin. Nature 422, 522–526 (2003).

    Article  CAS  Google Scholar 

  19. Kobayashi, K.S. et al. Nod2-dependent regulation of innate and adaptive immunity in the intestinal tract. Science 307, 731–734 (2005).

    Article  CAS  Google Scholar 

  20. Parks, W.C., Wilson, C.L. & Lopez-Boado, Y.S. Matrix metalloproteinases as modulators of inflammation and innate immunity. Nat. Rev. Immunol. 4, 617–629 (2004).

    Article  CAS  Google Scholar 

  21. Cadwell, K. et al. A key role for autophagy and the autophagy gene Atg16L1 in mouse and human intestinal Paneth cells. Nature 456, 259–263 (2008).

    Article  CAS  Google Scholar 

  22. Kaser, A. et al. XBP1 links ER stress to intestinal inflammation and confers genetic risk for human inflammatory bowel disease. Cell 134, 743–756 (2008).

    Article  CAS  Google Scholar 

  23. Wehkamp, J. et al. Reduced Paneth cell α-defensins in ileal Crohn's disease. Proc. Natl. Acad. Sci. USA 102, 18129–18134 (2005).

    Article  CAS  Google Scholar 

  24. Salzman, N.H. et al. Analysis of 16S libraries of mouse gastrointestinal microflora reveals a large new group of mouse intestinal bacteria. Microbiology 148, 3651–3660 (2002).

    Article  CAS  Google Scholar 

  25. Schloss, P.D. & Handelsman, J. Introducing DOTUR, a computer program for defining operational taxonomic units and estimating species richness. Appl. Environ. Microbiol. 71, 1501–1506 (2005).

    Article  CAS  Google Scholar 

  26. Turnbaugh, P.J. et al. An obesity-associated gut microbiome with increased capacity for energy harvest. Nature 444, 1027–1031 (2006).

    Article  Google Scholar 

  27. Ley, R.E., Turnbaugh, P.J., Klein, S. & Gordon, J.I. Microbial ecology: human gut microbes associated with obesity. Nature 444, 1022–1023 (2006).

    Article  CAS  Google Scholar 

  28. Turnbaugh, P.J., Backhed, F., Fulton, L. & Gordon, J.I. Diet-induced obesity is linked to marked but reversible alterations in the mouse distal gut microbiome. Cell Host Microbe 3, 213–223 (2008).

    Article  CAS  Google Scholar 

  29. Snel, J. et al. Comparison of 16S rRNA sequences of segmented filamentous bacteria Isolated from mice, rats, and chickens and proposal of “Candidatus Arthromitus”. Int. J. Syst. Bacteriol. 45, 780–782 (1995).

    Article  CAS  Google Scholar 

  30. Barman, M. et al. Enteric salmonellosis disrupts the microbial ecology of the murine gastrointestinal tract. Infect. Immun. 76, 907–915 (2008).

    Article  CAS  Google Scholar 

  31. Gill, S.E. & Parks, W.C. Metalloproteinases and their inhibitors: regulators of wound healing. Int. J. Biochem. Cell Biol. 40, 1334–1347 (2008).

    Article  CAS  Google Scholar 

  32. Swee, M., Wilson, C.L., Wang, Y., McGuire, J.K. & Parks, W.C. Matrix metalloproteinase-7 (matrilysin) controls neutrophil egress by generating chemokine gradients. J. Leukoc. Biol. 83, 1404–1412 (2008).

    Article  CAS  Google Scholar 

  33. Heczko, U., Abe, A. & Finlay, B.B. Segmented filamentous bacteria prevent colonization of enteropathogenic Escherichia coli 0103 in rabbits. J. Infect. Dis. 181, 1027–1033 (2000).

    Article  CAS  Google Scholar 

  34. Klaasen, H. et al. Intestinal segmented filamentous bacteria in a wide range of vertebrate species. Lab. Anim. 27, 141–150 (1993).

    Article  CAS  Google Scholar 

  35. Jiang, H.Q., Bos, N.A. & Cebra, J.J. Timing, localization, and persistence of colonization by segmented filamentous bacteria in the neonatal mouse gut depend on immune status of mothers and pups. Infect. Immun. 69, 3611–3617 (2001).

    Article  CAS  Google Scholar 

  36. Canny, G., Swidsinski, A. & McCormick, B.A. Interactions of intestinal epithelial cells with bacteria and immune cells: methods to characterize microflora and functional consequences. Methods Mol. Biol. 341, 17–35 (2006).

    CAS  PubMed  Google Scholar 

  37. Vaishnava, S., Behrendt, C.L., Ismail, A.S., Eckmann, L. & Hooper, L.V. Paneth cells directly sense gut commensals and maintain homeostasis at the intestinal host-microbial interface. Proc. Natl. Acad. Sci. USA 105, 20858–20863 (2008).

    Article  CAS  Google Scholar 

  38. Ivanov, I.I. et al. Specific microbiota direct the differentiation of IL-17-producing T-helper cells in the mucosa of the small intestine. Cell Host Microbe 4, 337–349 (2008).

    Article  CAS  Google Scholar 

  39. Hooper, L.V., Stappenbeck, T.S., Hong, C.V. & Gordon, J.I. Angiogenins: an new class of microbicidal proteins involved in innate immunity. Nat. Immunol. 4, 269–273 (2003).

    Article  CAS  Google Scholar 

  40. Hooper, L.V. et al. Molecular analysis of commensal host-microbial relationships in the intestine. Science 291, 881–884 (2001).

    Article  CAS  Google Scholar 

  41. Macpherson, A.J. & Uhr, T. Induction of protective IgA by intestinal dendritic cells carrying commensal bacteria. Science 303, 1662–1665 (2004).

    Article  CAS  Google Scholar 

  42. Peterson, D.A., McNulty, N.P., Guruge, J.L. & Gordon, J.I. IgA response to symbiotic bacteria as a mediator of gut homeostasis. Cell Host Microbe 2, 328–339 (2007).

    Article  CAS  Google Scholar 

  43. Salzman, N.H., Underwood, M.A. & Bevins, C.L. Paneth cells, defensins, and the commensal microbiota: a hypothesis on intimate interplay at the intestinal mucosa. Semin. Immunol. 19, 70–83 (2007).

    Article  CAS  Google Scholar 

  44. Ouellette, A.J. et al. Mouse Paneth cell defensins: primary structures and antibacterial activities of numerous cryptdin isoforms. Infect. Immun. 62, 5040–5047 (1994).

    CAS  PubMed  PubMed Central  Google Scholar 

  45. Porter, E.M., van Dam, E., Valore, E.V. & Ganz, T. Broad-spectrum antimicrobial activity of human intestinal defensin 5. Infect. Immun. 65, 2396–2401 (1997).

    CAS  PubMed  PubMed Central  Google Scholar 

  46. Sartor, R.B. Microbial influences in inflammatory bowel diseases. Gastroenterology 134, 577–594 (2008).

    Article  CAS  Google Scholar 

  47. Croswell, A., Amir, E., Teggatz, P., Barman, M. & Salzman, N.H. Prolonged impact of antibiotics on intestinal microbial ecology and susceptibility to enteric Salmonella infection. Infect. Immun. 77, 2741–2753 (2009).

    Article  CAS  Google Scholar 

  48. Wehkamp, J. et al. Paneth cell antimicrobial peptides: topographical distribution and quantification in human gastrointestinal tissues. FEBS Lett. 580, 5344–5350 (2006).

    Article  CAS  Google Scholar 

  49. Weigmann, B. et al. Isolation and subsequent analysis of murine lamina propria mononuclear cells from colonic tissue. Nat. Protoc. 2, 2307–2311 (2007).

    Article  CAS  Google Scholar 

  50. Haribhai, D., Edwards, B., Williams, M.L. & Williams, C.B. Functional reprogramming of the primary immune response by T cell receptor antagonism. J. Exp. Med. 200, 1371–1382 (2004).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank Y. Paterson (Department of Microbiology, University of Pennsylvania School of Medicine) for mentorship at the initiation of these studies (N.H.S.); D. Fish, P. Homolka and A. Croswell for technical assistance; the production staff at The Genome Center for sequencing the 16S rRNA genes; and J.A. Eisen and A.L. Hartman for discussions. Supported by the National Institutes of Health (AI057757 to N.H.S., and AI/DK50843 and AI32738 to C.L.B.), the Crohn's and Colitis Foundation of America (N.H.S.) and the Diabetes Foundation Netherlands (N.A.B).

Author information

Authors and Affiliations

Authors

Contributions

A collaboration between N.H.S. and C.L.B. resulted in the development of the DEFA5 transgenic mouse model and formulation of the underlying hypothesis; K.H. and N.H.S. developed the quantitative real-time PCR assays in collaboration with N.A.B.; M.S., K.H., P.T., M.H. and E.A. did bacterial genomic isolation and quantitative real-time PCR microbiota assays; D.E. did the statistical analysis of the data; M.B., N.A.B., Y.Z., E.S. and G.M.W. did subcloning, sequencing and clone analysis; D.H. and C.B.W. did LPL isolation and analysis by flow cytometry; H.C. J.K.-S. and C.L.B. contributed Paneth cell gene expression experiments; N.H.S. did the FISH studies and wrote the manuscript; N.H.S., K.H., E.A., C.L.B. and N.A.B. were responsible for interpretation of data; and all authors discussed the results and commented on the manuscript.

Corresponding author

Correspondence to Nita H Salzman.

Supplementary information

Supplementary Text and Figures

Supplementary Figures 1–2, Supplementary Tables 1–3 and Supplementary Methods (PDF 669 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Salzman, N., Hung, K., Haribhai, D. et al. Enteric defensins are essential regulators of intestinal microbial ecology. Nat Immunol 11, 76–82 (2010). https://doi.org/10.1038/ni.1825

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ni.1825

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing