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Immune responses to commensal and environmental microbes

An Erratum to this article was published on 01 December 2007

This article has been updated

Abstract

The mammalian immune system discriminates among microbes, inactivating pathogens while tolerating colonization by commensal organisms. Calibrating immune responses to microbes on this basis, however, is complex, as microbial virulence is often context dependent, being influenced by the host's immune status and the microbial milieu. Many microbial pathogens infecting immunocompromised hosts, for example, are innocuous in immune-competent individuals, and other microbes cause disease only when the commensal flora is compromised by antibiotic therapy. Recent studies have begun to reveal how the immune system tips the balance in favor of some microbes, allowing commensals to persist on mucosal surfaces while eliminating disease-causing pathogens.

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Figure 1: Intestinal pathogens and commensal microbes interact with the intestinal mucosa in a number of different ways.
Figure 2: Microbial interactions with the intestinal mucosa are complex and involve epithelial cells (blue) and bone marrow–derived dendritic cells (green).
Figure 3: Aspergillus fumigatus produces spores that are commonly inhaled.

Change history

  • 19 October 2007

    In the version of this article initially published, the citations for Figure 1 and Figure 2 are incorrect. The citations for Figure 2a, 2b and 2c should be 1a, 1b and 1c; the citations for Figure 1 should be Figure 2.The error has been corrected in the HTML and PDF versions of the article.

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Supported by the US National Institutes of Health and the Sandler Program for Asthma research.

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Pamer, E. Immune responses to commensal and environmental microbes. Nat Immunol 8, 1173–1178 (2007). https://doi.org/10.1038/ni1526

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