Presented at the Neonatal Society 2016 Spring Meeting.
Sava F1, Treszl A2, Hajdú J1, Rigó Jr J1, Tulassay T2, Vásárhelyi B3, Toldi G1
1 First Department of Obstetrics and Gynecology, Semmelweis University, Budapest, Hungary
2 First Department of Pediatrics, Semmelweis University, Budapest, Hungary
3 Department of Laboratory Medicine, Semmelweis University, Budapest, Hungary
Background: Vitamin D has an important immunomodulatory role. We hypothesized that the anti-inflammatory properties of vitamin D described in adults is also present in the preterm population. We investigated whether vitamin D levels at birth may associate with cellular and soluble indicators of the immune status in preterm infants. Effects of gestational age and plasma cortisol levels were also assessed.
Methods: Cord blood samples were collected from 28 preterm infants born ≤ 30 weeks of gestation. Ethical approval was obtained from the institution (Semmelweis University). Infants were divided into groups below and above median vitamin D level. We measured plasma cortisol and cytokine levels and also assessed the peripheral prevalence of distinct immune cell subsets using flow cytometry. The mixed effect model was used to analyse the effects of vitamin D, plasma cortisol levels and gestational age on cytokine levels and immune phenotype.
Results: Vitamin D level in our cohort was 23.3 (9.9-45.4) ng/ml. As evidenced by plasma IL-6 levels, none of the participants showed an acute inflammatory response at birth and no risk factors for sepsis other than prematurity were present. In infants with vitamin D level below the median, the prevalence of CD4+ CXCR3+ (Th1) and CD8+ CXCR3+ cell subsets was higher (5.86 (3.85-7.32) vs. 4.15 (2.68-5.73) and 9.01 (7.39-10.57) vs. 8.65 (6.80- 9.02), respectively), while the prevalence of CD4+ CCR4+ (Th2) and CD8+ CCR4+ cells (1.07 (0.36-1.94) vs. 1.56 (1.18-2.01), 0.12 (0.10-0.23) vs. 0.23 (0.09-0.75), respectively) as well as plasmacytoid dendritic cell (pDC) subsets was lower than in those with vitamin D level above median. pDCs and Th2 lymphocytes were the only cell subsets which were independently influenced by vitamin D levels, but not by plasma cortisol and gestational age. No association between vitamin D levels and any of the tested plasma cytokine levels was detected.
Conclusion: Vitamin D levels together with cortisol levels and gestational age were associated with the Th1/Th2 balance and the prevalence of plasmocytoid dendritic cells in the preterm infant. Vitamin D supplementation during pregnancy and after birth may influence adverse inflammatory response in this population.
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