ABSTRACT
BACKGROUND: Normal human skin is resistant to infection with various kinds of microorganisms by producing anti-microbial chemicals. Human beta defensin-2 (hBD-2) is an anti-microbial peptide that has recently been shown to be expressed in various epithelial cells and inflammatory diseases. However, the expression of hBD-2 in fungus-infected skin is not well-known. OBJECTIVE: This study was performed to investigate the expression pattern of hBD-2 in superficial mycosis. METHODS: Using the immunohistochemical method with formalin-fixed, paraffin-embedded sections, we checked the expression levels and localization of hBD-2 in lesional skin samples of tinea capitis (5 patients), tinea corporis (6 patients), candidiasis (3 patients), Malassezia folliculitis (2 patients), and psoriasis (3 patients) as positive control, and normal skin samples from 6 healthy subjects as negative control. RESULTS: The expression of hBD-2 was not observed in normal skin, but moderate to strong expression of hBD-2 was observed in the epidermis, and the papillary dermal infiltrating cells of psoriasis. In tinea capitis, strong hBD-2 expression was found in the upper spinous layer of epidermis and follicular epidermis, and perifollicular inflammatory cells. In tinea corporis and candidiasis, mild to strong expression of hBD-2 was found in the horny or spinous layer of epidermis and infiltrating inflammatory cells. Strong hBD-2 expression was found in the follicular epidermis and perifollicular inflammatory cells of Malassezia folliculitis. CONCLUSION: These results suggest that hBD-2 plays an important role in cutaneous innate immune defense against fungal infection.