Role of Active Vitamin D3 in Immunity

Abstract

ABSTRACT Introduction The active vitamin D3—1,25 dihydroxy cholecalciferol—is the key player in calcium and phosphorus metabolism and skeletal growth and functions. However, recent new developments have revealed its role in other tissues as well, referred to as the nonclassical actions of vitamin D. Not only the endocrinal effects, evidence indicates that vitamin D3 also has autocrine and paracrine functions due to its extrarenal synthesis by many cells, including the immune cells. All cells of the immune system have vitamin D receptors and show wide-ranging effects to it. It impacts both the innate and adaptive immune systems and the overall influence points to anti-infective, anti-inflammatory, immunosuppressive, and regulatory roles. It shows a significant role in chronic inflammatory and autoimmune diseases as well in susceptibility to infections. In this review, newer developments on the role of vitamin D in immunity and the underlying mechanism are discussed with possible future reflections. How to cite this article Verma R, Singh S, Singh B, Goswami B, Gupta SK. Role of Active Vitamin D3 in Immunity. Indian J Med Biochem 2017;21(2):166-175.