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[Michaelangelica]

Vitamin D seems crucial for the Immune Response to bacteria.

Originally published in Science Express on 23 February 2006
Science 24 March 2006:
Vol. 311. no. 5768, pp. 1770 - 1773
DOI: 10.1126/science.1123933


Toll-Like Receptor Triggering of a Vitamin D-Mediated Human Antimicrobial Response

In innate immune responses, activation of Toll-like receptors (TLRs) triggers direct antimicrobial activity against intracellular bacteria, which in murine, but not human, monocytes and macrophages is mediated principally by nitric oxide. We report here that TLR activation of human macrophages up-regulated expression of the vitamin D receptor and the vitamin D-1–hydroxylase genes, leading to induction of the antimicrobial peptide cathelicidin and killing of intracellular Mycobacterium tuberculosis. We also observed that sera from African-American individuals, known to have increased susceptibility to tuberculosis, had low 25-hydroxyvitamin D and were inefficient in supporting cathelicidin messenger RNA induction. These data support a link between TLRs and vitamin D–mediated innate immunity and suggest that differences in ability of human populations to produce vitamin D may contribute to susceptibility to microbial infection.

Toll-Like Receptor Triggering of a Vitamin D-Mediated Human Antimicrobial Response -- Liu et al. 311 (5768): 1770 -- Science
The right racial/genetic background helps:-

Vitamin D receptor gene polymorphism: association with Crohn's disease susceptibility J D Simmonsa, C Mullighanb, K I Welshb, D P Jewella

a Gastroenterology Unit, University of Oxford, Radcliffe Infirmary, Woodstock Rd, Oxford, OX2 6HE, UK, b Transplant Immunology, Transplant Centre, Churchill Hospital, Oxford, UK

Correspondence to: J D Simmons, Gastroenterology Unit, John Radcliffe Hospital, Oxford,

Accepted for publication 8 February 2000

BACKGROUND---The vitamin D receptor (VDR) gene represents a strong positional candidate susceptibility gene for inflammatory bowel disease (IBD).
The VDR gene maps to a region on chromosome 12 that has been shown to be linked to IBD by genome screening techniques.
It is the cellular receptor for 1,25(OH)2 vitamin D3 (calcitriol) which has a wide range of different regulatory effects on the immune system. IBD is characterised by activation of the mucosal immune system.
AIM---To determine if polymorphisms in the VDR gene are associated with susceptibility to IBD
SUBJECTS---European Caucasoids: 158 patients with ulcerative colitis, 245 with Crohn's disease, and 164 cadaveric renal allograft donor controls.
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CONCLUSION---This study provides preliminary evidence for a genetic association between Crohn's disease susceptibility and a gene that lies within one of the candidate regions determined by linkage analysis.

http://gut.bmj.com/cgi/content/abstract/47/2/211

I got so much Vit D today that my back has a warm red glow.