REVIEW - Vitamin D and host resistance to infection? Putting the cart in front of the horse

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Exp. Biol. Med. 2010;235:921-927

doi:10.1258/ebm.2010.010061

© 2010 Society for Experimental Biology and Medicine

Vitamin D and host resistance to infection? Putting the cart in front

of the horse

Danny Bruce, Jot Hui Ooi, Sanhong Yu and Margherita T Cantorna

Department of Veterinary and Biomedical Science, Center for Molecular

Immunology and Infectious Disease, The Pennsylvania State University,

115 Henning Bldg, University Park, PA 16802, USA

Abstract

Vitamin D is being touted as an anti-infective agent and it has even

been suggested that vitamin D supplementation could be effective

against the H1N1 influenza virus. The claims are largely based on the

ability of vitamin D to induce antibacterial peptides and evidence

that the immune system produces active vitamin D (1,25(OH)2D3) in

situ. While there are many examples of immune production of

1,25(OH)2D3 in vitro, there is little in vivo evidence.

In addition, it is not clear what role immune production of

1,25(OH)2D3 has on the course of disease. Vitamin D and 1,25(OH)2D3

inhibit T helper type 1 (Th1)/Th17-mediated immune responses and

autoimmune diseases by acting on the innate and acquired immune system

to inhibit the function of Th1 and Th17 cells. Th1 and Th17 cells are

important in host resistance to many infections including tuberculosis

(TB) caused by Mycobacterium tuberculosis.

Paradoxically the innate immune system is induced to produce

antibacterial peptides that are effective against TB in vitro. Data

from several models of infection have so far not supported a role for

vitamin D in affecting the course of disease. There is also very

little evidence that vitamin D affects the course of human TB

infection. Experiments have not been done in cells, mice or humans to

evaluate the effect of vitamin D on influenza virus.

At this time it would be premature to claim that vitamin D has an

effect on TB, influenza or any other infection.

Read the full article here:

http://ebm.rsmjournals.com/cgi/content/full/235/8/921

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