Vitamin D Deficiency in a Multiethnic Healthy Control Cohort and Altered Immune Response in Vitamin D Deficient European-American Healthy Controls

Abstract

ObjectiveIn recent years, vitamin D has been shown to possess a wide range of immunomodulatory effects. Although there is extensive amount of research on vitamin D, we lack a comprehensive understanding of the prevalence of vitamin D deficiency or the mechanism by which vitamin D regulates the human immune system. This study examined the prevalence and correlates of vitamin D deficiency and the relationship between vitamin D and the immune system in healthy individuals.MethodsHealthy individuals (n = 774) comprised of European-Americans (EA, n = 470), African–Americans (AA, n = 125), and Native Americans (NA, n = 179) were screened for 25-hydroxyvitamin D [25(OH)D] levels by ELISA. To identify the most noticeable effects of vitamin D on the immune system, 20 EA individuals with severely deficient (<11.3 ng/mL) and sufficient (>24.8 ng/mL) vitamin D levels were matched and selected for further analysis. Serum cytokine level measurement, immune cell phenotyping, and phosphoflow cytometry were performed.ResultsVitamin D sufficiency was observed in 37.5% of the study cohort. By multivariate analysis, AA, NA, and females with a high body mass index (BMI, >30) demonstrate higher rates of vitamin D deficiency (p<0.05). Individuals with vitamin D deficiency had significantly higher levels of serum GM-CSF (p = 0.04), decreased circulating activated CD4+ (p = 0.04) and CD8+ T (p = 0.04) cell frequencies than individuals with sufficient vitamin D levels.ConclusionA large portion of healthy individuals have vitamin D deficiency. These individuals have altered T and B cell responses, indicating that the absence of sufficient vitamin D levels could result in undesirable cellular and molecular alterations ultimately contributing to immune dysregulation.

The Hidden Function of Vitamin D

“…In our study vitamin D was in positive correlation with CD4 -that represent helper cells - which has found to contain the significant amount of VDR [40]. Our study was in agreement with (Ritterhouse et al) [41] vitamin D regulates T-helper 1 (Th1) and dendritic cell function [42], which suggest that vitamin D support the innate and the adaptive immune system.…”

Environmental Influences on Systemic Lupus Erythematosus Expression

“…Ritterhouse et al demonstrated among healthy controls that vitamin D deficiency was associated with autoimmunity (ANA positivity) 48 and with altered T and B cell responses, 51 consistent with low levels of 25(OH)D being a potential risk factor in the pathogenesis of SLE. Although causality remains to be determined, studies to date suggest a possible role for vitamin D in the pathogenesis of SLE.…”

Antigen nature and complexity influence human antibody light chain usage and specificity

“…The first cohort (Cohort 1) consisted of plasma samples from healthy donors from the Oklahoma Immune Cohort [19]. This cohort is well characterized for autoantibodies and all donors chosen for this study were autoantibody negative.…”