Human β-defensin-2 and psoriasin are overexpressed in lesions of acne inversa

Background: Acne inversa is a chronic inflammatory disorder of apocrine gland-bearing skin. The role of the innate immune system in the pathogenesis of the disease is controversial. Objectives: We investigated the expression of antimicrobial peptide/proteins in acne inversa. Methods: Tissue samples were obtained from patients with acne inversa and compared with normal-appearing skin. The expression of psoriasin and human beta-defensin (hBD)-2 on messenger RNA and protein level was analyzed. Results: Both messenger RNA and protein levels of psoriasin and hBD-2 were significantly increased in acne inversa. Macrophages expressing hBD-2 were found in the dermis. Limitations: Small sample size is a limitation. Conclusions: Antimicrobial peptide/proteins are overexpressed in acne inversa lesions as compared with normal-appearing skin. The site of the major expression depends on the particular antimicrobial peptide/protein. Psoriasin is overexpressed in epidermal keratinocytes whereas hBD-2 is produced mainly by dermal macrophages, leaving a relative deficiency of hBD-2 in the epidermis of acne inversa lesions. (J Am Acad Dermatol 2009;16:58-65.)