Mechanisms underlying the effect of vitamin D on the immune system.
Vitamin D and the vitamin D receptor (VDR) have been shown to be important regulators of the immune system. In particular, vitamin D and VDR deficiency exacerbates experimental autoimmune diseases such as inflammatory bowel disease (IBD). IBD develops due to an immune-mediated attack by pathogenic T-cells that overproduce IL-17 and IFN-gamma and a few regulatory cells. VDR knockout mice have twice as many T-cells making IL-17 and IFN-gamma than wild-type mice. In addition, vitamin D and the VDR are required for normal numbers of regulatory T-cells (iNKT and CD8alphaalpha) that have been shown to suppress experimental IBD. In the absence of vitamin D and the VDR, autoimmunity occurs in the gastrointestinal tract due to increased numbers of IL-17 and IFN-gamma secreting T-cells and a concomitant reduction in regulatory T-cells.
Center for Molecular Immunology and Infectious Disease, Department of Veterinary and Biomedical Science, The Pennsylvania State University, 115 Henning Bldg, University Park, PA 16802, USA. mxc69@psu.edu
Margherita T
MT
Cantorna
D000818:Animals; D001327:Autoimmune Diseases / Q000378:metabolism*; D004195:Disease Models, Animal; D015212:Inflammatory Bowel Diseases / Q000276:immunology* / Q000378:metabolism; D020381:Interleukin-17 / Q000378:metabolism; D007420:Intestine, Large / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D018167:Receptors, Calcitriol / Q000378:metabolism*; D013601:T-Lymphocytes / Q000378:metabolism*; D014807:Vitamin D / Q000378:metabolism*; D014808:Vitamin D Deficiency / Q000150:complications / Q000276:immunology*
D020381:Interleukin-17; D018167:Receptors, Calcitriol; D014807:Vitamin D