Effect of vitamin D deficiency on the hepatitis-B-vaccine immune response in healthy population

To determine the potential associations among vitamin D, metabolic enzymes, vitamin D receptors (VDR) and hepatitis-B vaccine and whether vitamin D processing is involved in human hepatitis-B-vaccine immune response mechanisms in a healthy population, 100 healthy subjects who underwent active hepatitis B immunization were included in this study. These subjects included seroprotection (n=30, titer > 100 U/L), non-responders (n=40, titer 1-9 U/L) and low-responders (n=30, titer 10-100 U/L). The responders contained low-responders and seroprotection (n=60, titer >= 10 U/L). 25-hydroxyvitamin D (25(OH)D) levels were measured by an chemiluminiscent immunoassay. The expression of vitamin D metabolic enzymes (CYP24A1 and CYP27B1) and VDR in peripheral blood mononuclear cells (PBMC) were measured using quantitative RT-PCR. The non-responders showed lower 25(OH)D levels than the responders, but the difference was not significant (P > 0.05). The gene expression of VDR, CYP27B1 and CYP24A1 in PBMCs was not significantly different among the various groups. Our data suggested that vitamin D levels were not significantly different between the responders and the non-responders and vitamin D processing by PBMCs maybe not impaired in non-responders.