Abstract
The mammalian intestinal tract harbors a diverse community of trillions of microorganisms, which have co-evolved with the host immune system for millions of years. Many of these microorganisms perform functions critical for host physiology, but the host must remain vigilant to control the microbial community so that the symbiotic nature of the relationship is maintained. To facilitate homeostasis, the immune system ensures that the diverse microbial load is tolerated and anatomically contained, while remaining responsive to microbial breaches and invasion. Although the microbiota is required for intestinal immune development, immune responses also regulate the structure and composition of the intestinal microbiota. Here we discuss recent advances in our understanding of these complex interactions and their implications for human health and disease.
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Change history
20 September 2013
In the version of this article initially published, a label was missing from Figure 2. The lymphoid structure in the large intestine should be labeled 'Isolated lymphoid follicle'. The error has been corrected in the HTML and PDF versions of the article.
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Acknowledgements
We thank M. Wlodarska, L. Reynolds and N. Gill for the critical revision of this manuscript and thoughtful insights. The Finlay laboratory is supported by operating grants from Canadian Institutes of Health Research.
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Brown, E., Sadarangani, M. & Finlay, B. The role of the immune system in governing host-microbe interactions in the intestine. Nat Immunol 14, 660–667 (2013). https://doi.org/10.1038/ni.2611
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DOI: https://doi.org/10.1038/ni.2611
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