Recent advances in understanding how the mammalian immune system and intestinal microbiota functionally interact have yielded novel insights for human health and disease. Modern technologies to quantitatively measure specific members and functional characteristics of the microbiota in the gastrointestinal tract, along with fundamental and emerging concepts in the field of immunology, have revealed numerous ways in which host-microbiota interactions proceed beneficially, neutrally, or detrimentally for mammalian hosts. It is clear that the gut microbiota has a strong influence on the shape and quality of the immune system; correspondingly, the immune system guides the composition and localization of the microbiota. In the following review, we examine the evidence that these interactions encompass homeostasis and inflammation in the intestine and, in certain cases, extraintestinal tissues. Lastly, we discuss translational therapies stemming from research on host-microbiota interactions that could be used for the treatment of chronic inflammatory diseases.
This work was supported by National Institutes of Health Grants DP5OD012116, R01AI123368, R21DK110262, and U01AI095608, the National Institute of Allergy and Infectious Diseases Mucosal Immunology Studies Team, the Crohn’s and Colitis Foundation of America, the Searle Scholars Program, and an American Asthma Foundation Scholar Award.
Abbreviations used in this article:
- aryl hydrocarbon receptor
- Crohn’s disease
- experimental autoimmune encephalitis
- fecal microbiota transplant therapy
- inflammatory bowel disease
- intestinal epithelial cell
- innate lymphoid cell
- group 3 ILC
- microbe-associated molecular pattern
- polysaccharide A
- rheumatoid arthritis
- short-chain fatty acid
- segmented filamentous bacteria
- regulatory T cell
- Received September 19, 2016.
- Accepted October 31, 2016.
- Copyright © 2017 by The American Association of Immunologists, Inc.