Prenatal vitamin D₃ supplementation suppresses LL-37 peptide expression in ex vivo activated neonatal macrophages but not their killing capacity.
Raqib. Rubhana R; Ly. Anna A; Akhtar. Evana E; Mily. Akhirunnesa A; Perumal. Nandita N; Al-Mahmud. Abdullah A; Rekha. Rokeya Sultana RS; Hel Baqui. Abdullah A; Roth. Daniel E DE
Key Findings
- Prenatal vitamin D (0.875 mg weekly) reduced intracellular LL‑37 levels in activated cord‑blood macrophages.
- Vitamin D did not increase LL‑37 levels in plasma or in the fluid outside the cells.
Practical Outcomes
- For biohackers, the study suggests that prenatal vitamin D can modulate a specific immune peptide without harming basic bacterial killing, but it offers no clear protocol change for non‑pregnant adults. The finding mainly confirms that vitamin D influences innate immunity markers, so it’s more of a safety/knowledge point than a direct actionable strategy.
Summary
Giving pregnant women a weekly dose of vitamin D lowered the amount of the antimicrobial peptide LL‑37 inside newborn immune cells when those cells were activated, but it didn’t change the cells' ability to kill bacteria in lab tests.
Abstract
Vitamin D has regulatory effects on innate immunity. In the present study, we aimed to assess the effect of prenatal vitamin D₃ (vitD₃) supplementation on neonatal innate immunity in a randomised, placebo-controlled trial by evaluating cathelicidin (LL-37) expression and the killing capacity of macrophages. Healthy pregnant women (n 129) attending a clinic in Dhaka were randomised to receive either a weekly oral dose of 0·875 mg vitD₃ or placebo starting from 26 weeks of gestation up to delivery. Serum, plasma and monocyte-derived macrophages (MDM) were obtained from the cord blood. 25-Hydroxyvitamin D (25(OH)D) concentration was measured in serum. MDM were stimulated with or without Toll-like-receptor 4 ligand (TLR4L). Innate immune function was assessed by measuring LL-37 peptide levels in the culture supernatant of MDM by ELISA, LL-37 transcript levels by quantitative PCR, and ex vivo bactericidal capacity of MDM. VitD₃ supplementation did not increase LL-37 peptide levels in plasma or in the extracellular fluid of macrophages with or without TLR4L induction. However, stimulated intracellular LL-37 expression (ratio of stimulated:unstimulated MDM) was significantly reduced in the vitamin D group v. placebo (P=0·02). Multivariate-adjusted analyses showed that intracellular LL-37 peptide concentration from stimulated MDM was inversely associated with 25(OH)D concentration in serum (P=0·03). TLR4L stimulation increased the bactericidal capacity of MDM compared with the unstimulated ones (P=0·01); however, there was no difference in killing capacity between the two groups. A weekly dose of 0·875 mg vitD₃ to healthy pregnant women suppressed the intracellular LL-37 peptide stores of activated macrophages, but did not significantly affect the ex vivo bactericidal capacity of cord blood MDM.
Study Information
pubmed
2014
2014-08-04T00:00:00.000Z
10.1017/s0007114514001512