Vitamin D receptor (VDR) gene variants are shown to regulate immune response in tuberculosis. We studied the influence of
VDR promoter (Cdx-2 and A1012G), 3′ untranslated region (
Apa I,
Bsm I, and
Taq I) and start codon (
Fok I) polymorphisms on 1,25(OH)
2D
3-modulated IL-12p40, IFN-γ, IL-10, and IL-5 response to live
Mycobacterium tuberculosis and its culture filtrate antigen (CFA) in 60 normal healthy subjects and 51 pulmonary tuberculosis patients. In peripheral
blood mononuclear cell cultures with CFA and 1,25(OH)
2D
3, IL-12p40, and IFN-γ levels were significantly decreased (
p < 0.05) and IL-10 levels were significantly increased (
p < 0.05) in patients with GG genotype. The extended genotype bbaaTT (baT haplotype) was associated with decreased IL-12p40
and IFN-γ levels and significantly increased IL-10 levels (
p < 0.05). The Cdx-2 GG genotype and baT haplotype are associated with a suppressed Th1 and increased IL-10 response, which
suggests that 1,25(OH)
2D
3 probably through the VDR polymorphic variants augments the anti-inflammatory response at the site of
M. tuberculosis infection.
Keywords Vitamin D receptor - cytokines - gene polymorphism - tuberculosis