The Effect of Calcipotriol on the Expression of Human β Defensin-2 and LL-37 in Cultured Human Keratinocytes

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.