[Update on recent progress in vitamin D research. The effects of vitamin D in autoinflammatory diseases.]

Various kinds of immune cells -including dendritic cells, macrophages, T cells and B cells- express the vitamin D receptor and 1α-hydroxylase(CYP27B1). In vitro studies have shown the anti-inflammatory effect of 1,25-dihydroxyvitamin D:the active form of vitamin D. As vitamin D deficiency spread in our society, epidemiological studies have established the association between vitamin D deficiency and incidence or progression of several inflammatory diseases, including rheumatoid arthritis(RA), systemic lupus erythematosus(SLE), and multiple sclerosis(MS). In addition, recently the property of vitamin D for treatment or prevention is debated. Here, we review the recent epidemiological evidence associated with vitamin D and inflammatory diseases, and describe the immunomodulatory effect of vitamin D underlying it.