Increased vitamin D is associated with decline of naïve, but accumulation of effector, CD8 T cells during early aging

Abstract

Given the protective roles of 25-hydroxyvitamin D (25[OH]D or vitamin D) in musculoskeletal health and the potential beneficial effects of vitamin D supplementation in reducing the risk of various chronic diseases, intensive repletion of vitamin D has been widely advocated. Of note, CD8 T cells have the highest levels of the vitamin D receptor compared with other major immune cells. The effects of vitamin D on CD8 T cells during aging, however, remain unclear. This study determined the relationship between vitamin D levels and CD8 T-cell status in 34 healthy female subjects (all >60 years old). The CD8 T cell phenotype was defined by the surface expression of CD28 and CD95. The low-25(OH)D serum groups (≤30 ng/ml) had higher percentages of CD28+CD95−CD8+ (naïve) T cells and lower percentages of CD28+CD95+CD8+ (effector) T cells. By contrast, subjects with high levels of 25(OH)D had very low percentages of naïve CD8 T cells but very high percentages of effector CD8 T cells. There was a significant inverse correlation between 25(OH)D levels and the frequency of naïve CD8 T cells. The results show that higher levels of vitamin D are correlated with decreased frequencies of naïve CD8 T cells during early aging, suggesting that higher levels of 25(OH)D accelerate CD8 T-cell senescence. These results warrant the further evaluation of the effects of vitamin D supplementation in immune aging.

The role of vitamin D on circulating memory T cells in children: The Generation R study

“…In line with our observations, previous studies reported positive associations between 25(OH)D and T lymphocyte differentiation into Tem cells, and between 25(OH)D and activated T cells . However, these studies were limited by their study population (small sample size, adult or mouse populations) or lack of adjustment for possible confounders as season of blood draw, herpes seropositivity, and lifestyle determinants.…”

“…This is in line with observations from adult studies . The effects of vitamin D on T‐cell activation are likely to affect the formation of immunological memory …”

“…Tem cells, and between 25(OH)D and activated T cells. [8][9][10] However, these studies were limited by their study population (small sample size, adult or mouse populations) or lack of adjustment for possible confounders as season of blood draw, herpes seropositivity, and lifestyle determinants. Our results therefore extend observations from previous studies.…”

“…8 This is in line with observations from adult studies. 9,10 The effects of vitamin D on T-cell activation are likely to affect the formation of immunological memory. 9,10 No studies on 25-hydroxyvitamin D (25(OH)D) and the maturation of T memory cells in children have been performed.…”

“…9,10 The effects of vitamin D on T-cell activation are likely to affect the formation of immunological memory. 9,10 No studies on 25-hydroxyvitamin D (25(OH)D) and the maturation of T memory cells in children have been performed. Because Tcell numbers are highly dynamic in the first 5 years of life after which these stabilize, we examined the association between 25(OH)D and circulatory naive, central memory, and effector memory T lymphocyte numbers in 3189 6-year-old children.…”