Vitamin D, Autoimmune Disease and Rheumatoid Arthritis

Vitamin D has been reported to influence physiological systems that extend far beyond its established functions in calcium and bone homeostasis. Prominent amongst these are the potent immunomodulatory effects of the active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). The nuclear vitamin D receptor (VDR) for 1,25-(OH)2D3 is expressed by many cells within the immune system and resulting effects include modulation of T cell phenotype...