Abstract
Commensal flora plays an important role in the development of the mucosal immune system and in maintaining intestinal homeostasis. However, the mechanisms involved in regulation of host-microbiota interaction are still not completely understood. In this study, we examined how microbiota and intestinal inflammatory conditions regulate host microRNA expression and observed lower microRNA-107 (miR-107) expression in the inflamed intestines of colitic mice, compared with that in normal control mice. miR-107 was predominantly reduced in epithelial cells and CD11c+ myeloid cells including dendritic cells and macrophages in the inflamed intestines. We demonstrate that IL-6, IFN-γ, and TNF-α downregulated, whereas TGF-β promoted, miR-107 expression. In addition, miR-107 expression was higher in the intestines of germ-free mice than in mice housed under specific pathogen-free conditions, and the presence of microbiota downregulated miR-107 expression in DCs and macrophages in a MyD88- and NF-κB-dependent manner. We determined that the ectopic expression of miR-107 specifically repressed the expression of IL-23p19, a key molecule in innate immune responses to commensal bacteria. We concluded that regulation of miR-107 by intestinal microbiota and proinflammatory cytokine serve as an important pathway for maintaining intestinal homeostasis.
Original language | English (US) |
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Pages (from-to) | 673-682 |
Number of pages | 10 |
Journal | European Journal of Immunology |
Volume | 44 |
Issue number | 3 |
DOIs | |
State | Published - Mar 2014 |
Keywords
- IL-23p19
- Inflammatory bowel disease
- MiR-107
- MicroRNAs
- TLR
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology