Impact of vitamin D administration on immunogenicity of trivalent inactivated influenza vaccine in previously unvaccinated children

Vitamin D, leptin and impact on immune response to seasonal influenza A/H1N1 vaccine in older persons

“…We did not find a significant correlation for baseline 25-(OH) D levels with humoral immune outcomes such as HAI (which is in agreement with other studies), 9,12,26 VNA or B-cell ELISPOT. Previous studies have not evaluated CMI outcomes.…”

“…Previous studies have not evaluated CMI outcomes. 9,12,26 We found a weak positive correlation between baseline 25-(OH) D levels and change in influenza-specific granzyme B cellular response at Day 75 compared to Day 0 (Spearman's rank correlation coefficient 0.16, p D 0.04). Granzyme B is a serine protease produced by NK cells, dendritic cells and cytotoxic T cells.…”

“…51,52 Finally, the strategy of vitamin D supplementation or use as a vaccine adjuvant needs to be explored further, instead of merely optimizing "homeostatic" 25-(OH) D status. [10][11][12][13]26,53,54 Several studies involving mature adult mice that were immunized subcutaneously or intramuscularly with inactivated vaccine (inactivated polio vaccine, 53 Haemophilus influenzae type b oligosaccharide conjugated to diphtheria toxoid vaccine, 54 and hepatitis B surface antigen (HBsAg) 55 ), co-administered with 1,25-(OH) 2 D3 demonstrated production of antigen-specific mucosal immunity (IgA and IgG antibodies), as well as enhanced systemic immune responses. It is likely that vitamin D is not an independent predictor of a binary outcome, but may be influential through its complex immune physiological interactions.…”

“…9,10,12 The immune responses studied were for the influenza A/H1N1 strain (majority of subjects had baseline H1N1 HAI titer 1:40); it will be important to evaluate responses to A/H3N2 and B strains as well. This is the first study, to our knowledge, to assess the effect of 25-(OH) D levels on CMI outcome to influenza vaccination.…”

“…Few studies have included subjects already on vitamin D supplementation. [9][10][11][12][13] Epidemiological studies have demonstrated a higher incidence of vitamin D deficiency in elderly and obese populations. 14,15 Recent findings from a longitudinal study of older adults suggest leptin may mediate obesity-related vitamin D deficiency.…”