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Study · Measured the body's own peptide · 2015

2 results

Vitamin D, serum 25(OH)D, LL-37 and polymorphisms in a Canadian First Nation population with endemic tuberculosis.

Larcombe L, Mookherjee N, Slater J, Slivinski C, Dantouze J, Singer M, Whaley C, Denechezhe L, Matyas S, Decter K, Turner-Brannen E, Ramsey C, Nickerson P, Orr P

International journal of circumpolar health19 Aug 2015Cited by 13 (Europe PMC)

PMID26294193 (opens in a new tab)PMCIDPMC4543449 (opens in a new tab)DOI10.3402/ijch.v74.28952 (opens in a new tab)PepBankPUB-26294193
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Summary

BackgroundCanadian First Nation populations have experienced endemic and epidemic tuberculosis (TB) for decades. Vitamin D-mediated induction of the host defence peptide LL-37 is known to enhance control of pathogens such as Mycobacterium tuberculosis.ObjectiveEvaluate associations between serum levels of 25-hydroxy vitamin D (25(OH)D) and LL-37, in adult Dene First Nation participants (N = 34) and assess correlations with single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) and vitamin D binding protein (VDBP).DesignVenous blood was collected from all participants at baseline (winter and summer) and in conjunction with taking vitamin D supplements (1,000 IU/day) (winter and summer). Samples were analysed using ELISA for concentrations of vitamin D and LL-37, and SNPs in the VDR and VDBP regions were genotyped.ResultsCirculating levels of 25(OH)D were not altered by vitamin D supplementation, but LL-37 levels were significantly decreased. VDBP and VDR SNPs did not correlate with serum concentrations of 25(OH)D, but LL-37 levels significantly decreased in individuals with VDBP D432E T/G and T/T, and with VDR SNP Bsm1 T/T genotypes.ConclusionsOur findings suggest that vitamin D supplementation may not be beneficial as an intervention to boost innate immune resistance to M. tuberculosis in the Dene population.
CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study2

No result from this study comes from a test of the peptide.

Natural levels measured2

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

  1. 01HumanEndogenous levelNon-randomized trialOther

    In adult Dene First Nation participants, vitamin D supplementation was followed by a significant decrease in serum LL‑37 levels, while 25(OH)D was not altered.

    In plain wordsIn adults taking vitamin D, the body's own LL‑37 level in blood fell, while vitamin D blood level did not change.

    Peptide
    LL-37
    Outcome
    DecreaseSerum LL-37 with vitamin D supplementation
    Study

    n = 34

    Comparator
    Baseline before supplementation
    Outcome group
    Immune response · Infection

    Source sentences

    Summary
    Circulating levels of 25(OH)D were not altered by vitamin D supplementation, but LL-37 levels were significantly decreased.
    2 context sentences
    Summary · context
    Evaluate associations between serum levels of 25-hydroxy vitamin D (25(OH)D) and LL-37, in adult Dene First Nation participants (N = 34) and assess correlations with single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) and vitamin D binding protein (VDBP).
    Summary · context
    Venous blood was collected from all participants at baseline (winter and summer) and in conjunction with taking vitamin D supplements (1,000 IU/day) (winter and summer).

    This result measures the body's own LL-37. Nobody was given the peptide. It is not evidence about taking it.

  2. 02HumanEndogenous levelNon-randomized trialOther

    Serum LL‑37 levels decreased significantly in individuals with VDBP D432E T/G and T/T genotypes and VDR Bsm1 T/T genotype.

    In plain wordsIn adults with certain vitamin D gene variants, the body's own LL‑37 level fell after vitamin D supplements.

    Peptide
    LL-37
    Outcome
    DecreaseSerum LL-37 by VDBP and VDR genotype
    Study

    n: not reported in source

    Comparator
    Baseline before supplementation
    Outcome group
    Immune response · Infection

    Source sentences

    Summary
    VDBP and VDR SNPs did not correlate with serum concentrations of 25(OH)D, but LL-37 levels significantly decreased in individuals with VDBP D432E T/G and T/T, and with VDR SNP Bsm1 T/T genotypes.
    2 context sentences
    Summary · context
    Evaluate associations between serum levels of 25-hydroxy vitamin D (25(OH)D) and LL-37, in adult Dene First Nation participants (N = 34) and assess correlations with single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) and vitamin D binding protein (VDBP).
    Summary · context
    Venous blood was collected from all participants at baseline (winter and summer) and in conjunction with taking vitamin D supplements (1,000 IU/day) (winter and summer).

    This result measures the body's own LL-37. Nobody was given the peptide. It is not evidence about taking it.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 3Current

    11 Oct 2026, 00:50 UTC

    Study results updated

  2. Version 2

    9 Oct 2026, 03:03 UTC

    Study data updated · source update from Europe PMC

  3. Version 1

    9 Oct 2026, 02:57 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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