Regional Control of Regulatory Immune Cells in the Intestine
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Purpose of Review
The intestine contains the largest compartment of immune regulatory cells which include T regulatory cells and IL-10-producing macrophages. These cell populations serve to restrain unnecessary immune responses of the intestine, which may lead to the pathogenesis of Crohn’s disease or food allergy.
This review discusses the recent findings pertaining to the functional regulation of these cells which may provide insight into novel therapies. Both T regulatory cells and macrophages are regulated in microbiota-dependent and microbiota-independent manners, i.e., dietary antigens. Often, this is specific to regional specialization and environment in small intestine vs. colon.
These immune regulatory cells are largely regulated by microbiota in the colon, whereas in the small intestine, the microbiota has less affect, as seen in germ-free mouse studies. Targeting these cells in their specific compartments may direct future treatment modalities for inflammatory bowel disease as ulcerative colitis and Crohn’s are vastly different diseases.
KeywordsGut immune system Regulatory T cells Macrophages Interleukin-10 Gut microbiota Dietary antigen
This work was supported by NIH T32 DK094775 (T.L.M.), DK110146 and DK108901 (N.K.).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
T.L.M, J.Y.K, and N.K. have no financial conflicts of interest. A.H. is employed by Miyarisan Pharmaceutical Co., Ltd.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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