Vitamin D and immune system.

Abstract

The active metabolite of vitamin D 1,25(OH)₂D is well known for its role in regulating calcium-phosphate homeostasis of the human body. However, the immunomodulating activity of 1,25(OH)₂D has been known for many years. There are numerous reports correlating low vitamin D levels in blood serum with the onset of autoimmune diseases and with the severe course of acute infections. In this chapter, we address the role of 1,25(OH)₂D in these diseases, and we discuss the possible mechanisms of action of 1,25(OH)₂D in immune cells.