Jansen PA, Rodjik-Olthuis D, Hollox EJ et al. PLoS One 2009;4:e4725.
Human β-defensin-2 (HBD-2) is strongly expressed in the lesional epidermis of patients with psoriasis. In the current article, the investigators analyzed the expression of HBD-2 in the serum of patients with psoriasis, and found that high concentrations of HBD-2 are secreted by lesional psoriatic skin, and that systemic levels of HBD-2 correlate well with disease activity in plaque psoriasis.
β-defensins are secreted peptides that are expressed by epithelia and have antimicrobial and chemotactic properties. They are involved in antimicrobial responses against various pathogens. In the current article, Jansen et al. investigated the serum levels, genetic copy numbers, and epithelial expression of β-defensins in healthy individuals and in patients with atopic diseases, rheumatoid arthritis (RA), or plaque psoriasis. The serum levels of β-defensins correlated with the copy number of the encoding gene in healthy individuals, but no correlation between these two parameters could be found in patients with psoriasis. However, the Psoriasis Area and Severity Index (PASI) scores had a significant linear correlation with the serum levels of β-defensins, which were 100-fold higher in severe cases than in healthy individuals and atopic patients. In addition, the levels of β-defensins in atopic individuals and in patients with RA were higher compared with those in healthy controls. The authors also demonstrated that there was a difference in the levels of expression of the three different types of β-defensin by performing biopsies on all major organs.