Positive correlation between circulating cathelicidin antimicrobial peptide (hCAP18/LL-37) and 25-hydroxyvitamin D levels in healthy adults

Abstract

BackgroundTranscription of the cathelicidin antimicrobial peptide (CAMP) gene is induced by binding of the bioactive form of vitamin D, 1,25-dihydroxyvitamin D, to the vitamin D receptor. Significant levels of the protein hCAP18/LL-37 are found in the blood and may protect against infection and/or sepsis. We hypothesized that serum vitamin D levels may modulate the circulating levels of hCAP18. Only three studies have shown a positive correlation between circulating 25-hydroxyvitamin D and hCAP18 levels. Here we provide additional evidence for such a correlation in healthy, middle-aged adults.FindingsSerum levels of 25-hydroxyvitamin D [25(OH)D] and plasma levels of hCAP18 were determined in 19 healthy middle-aged (mean of 50.1 years) adult men and women. Plasma hCAP18 concentrations correlated with serum 25(OH)D concentrations in subjects with 25(OH)D levels ≤ 32 ng/ml (r = 0.81, p < 0.005) but not in subjects with concentrations > 32 ng/ml (r = 0.19, p = 0.63).ConclusionsWe conclude that plasma hCAP18 levels correlate with serum 25(OH)D levels in subjects with concentrations of 25(OH)D ≤ 32 ng/ml as opposed to those with concentrations > 32 ng/ml and that vitamin D status may regulate systemic levels of hCAP18/LL-37.

Association Between Preoperative 25-Hydroxyvitamin D Level and Hospital-Acquired Infections Following Roux-en-Y Gastric Bypass Surgery

“…As such, LL-37 may provide important first-line defense mechanisms for the innate immune system. 46 Prospective studies by members of our research group and others have shown maximal LL-37 expression to occur at 25(OH)D levels between 30 and 35 ng/mL, 47,48 thereby strengthening the biological basis for the association between higher 25(OH)D levels and optimal immune function.…”

Human Cathelicidin Production by the Cervix

“…A study conducted by Dixon et al in healthy adults identified a positive correlation between circulating plasma hCAP18/LL-37 and serum 25(OH) vitamin D in subjects with 25(OH) vitamin D levels ≤80 nmol/L as opposed to those with concentrations >80 nmol/L [28]. Bhan et al also found a positive correlation between serum 25(OH) vitamin D levels <80 nmol/l and baseline hCAP18/LL-37 levels, and changes in hCAP18/LL-37 levels after high-dose vitamin D 2 , ergocalciferol treatment [29].…”

Local Sustained Delivery of 25-Hydroxyvitamin D3 for Production of Antimicrobial Peptides

“…Direct peptide application and over expression following gene therapy approaches have been precluded because of a number of significant toxicity issues (15-19). Additionally, direct administration of 1,25-hydroxyvitamin D 3 does induce hCAP 18 expression but low concentrations (10 −7 M 1,25-hydroxyvitamin D 3 ) generate cytotoxicity and led to the inhibition of cell growth (41-43). Other strategies are therefore needed to improve hCAP 18 expressions and LL-37 productions.…”