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The gut flora as a forgotten organ
Open accessAbstract
The intestinal microflora is a positive health asset that crucially influences the normal structural and functional development of the mucosal immune system. Mucosal immune responses to resident intestinal microflora require precise control and an immunosensory capacity for distinguishing commensal from pathogenic bacteria. In genetically susceptible individuals, some components of the flora can become a liability and contribute to the pathogenesis of various intestinal disorders, including inflammatory bowel diseases. It follows that manipulation of the flora to enhance the beneficial components represents a promising therapeutic strategy. The flora has a collective metabolic activity equal to a virtual organ within an organ, and the mechanisms underlying the conditioning influence of the bacteria on mucosal homeostasis and immune responses are beginning to be unravelled. An improved understanding of this hidden organ will reveal secrets that are relevant to human health and to several infectious, inflammatory and neoplastic disease processes.
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“In the absence of the resident microbiota, members of the TLR family have low or absent expression profiles in the gut, thus compromising appropriate neuroendocrine responses to pathogenic threats (O'Hara and Shanahan, 2006).”
From The Microbiota-Gut-Brain Axis (2019) · cites this paper as O'Hara and Shanahan, 2006
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“Microbial abundance and community structure in the proximal intestine is affected by gastric acid, pancreaticobiliary secretions, and fast transit45.”
From The gut Microbiome in adult and pediatric functional gastrointestinal disorders (2019) · cites this paper as [45]
In the citing paper
“Studies have since shown that gut bacteria play a vital role in regulating important aspects of brain development and function, along with other host physiology [5, 7].”
From Effect of fecal microbiota transplant on symptoms of psychiatric disorders: a systematic review (2020) · cites this paper as [5]
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- Rook GA, Brunet LR (2005) Microbes, immunoregulation and the gut. Gut 54: 317–320
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Cryan, J. F., O'Riordan, K. J., Cowan, C. S. M., Sandhu, K. V., Bastiaanssen, T. F. S., Boehme, M., Codagnone, M. G., Cussotto, S., Fulling, C., Golubeva, A. V., et al. (2019) · Physiological Reviews · doi:10.1152/physrev.00018.2018 · Cited by 5,286
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Metadata
- Authors
- O'Hara, A. M., & Shanahan, F.
- Affiliations
- National University of Ireland (IE)
- Corresponding author
- Shanahan, Fergus
- ORCID
- Shanahan, Fergus
- Venue
- The EMBO Reports
- Published
- 2006-07-01
- Volume
- 7
- Issue
- 7
- Pages
- 688-693
- ISSN
- 1469-221X (ISSN-L)
- 1469-3178
- PMC
- PMC1500832
- OpenAlex
- W2117727476
- Cited by
- 2,791
- References
- 54
- Citations by year
- 2026: 67 · 2025: 127 · 2024: 186 · 2023: 174 · 2022: 230 · 2021: 217 · 2020: 243 · 2019: 198 · 2018: 179 · 2017: 184 · 2016: 168 · 2015: 147 · 2014: 123 · 2013: 134 · 2012: 121
- FWCI
- 3.21
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- EMBO Reports (publishedVersion)
- Europe PMC (PubMed Central) (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Science Foundation Ireland
- Alimentary Health
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
- Life Sciences › Agricultural and Biological Sciences › Food Science › Probiotics and Fermented Foods
- Health Sciences › Medicine › Gastroenterology › Inflammatory Bowel Disease
- Keywords
- gut microbiota, mucosal immunity, inflammatory bowel disease, mucosal homeostasis, bacterial metabolic activity, microbiome manipulation, intestinal disorders, pathogenesis
- MeSH terms
- Animals, Bacteria, Digestive System, Digestive System Diseases, Germ-Free Life, Homeostasis, Humans, Intestinal Mucosa, Models, Biological, Immunity, Mucosal
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