Background: Vitamin D has been reported to regulate innate immunity by controlling the expression of antimicrobial peptides (AMPs).
Objective: We investigated the effect of calcipotriol on the expression of AMPs in human cultured keratinocytes.
Methods: Keratinocytes were treated with lipopolysaccharide (LPS), TNF-alpha, Calcipotriol and irradiated with UVB, cultured, and harvested. To assess the expression of human beta defensin-2 and LL-37 in the control group, not exposed to any stimulants, the experimental group was treated with LPS, TNF-alpha, or UVB, and another group was treated again with calcipotriol; reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemical staining were performed.
Results: In the experimental group treated with LPS, UVB irradiation, and TNF-alpha, the expression of beta-defensin and LL-37 was increased more than in the control group and then decreased in the experimental group treated with calcipotriol.
Conclusions: Calcipotriol suppressed HBD-2 and LL-37, which were stimulated by UVB, LPS, and TNF-alpha.