CC chemokines as potential immunologic markers correlated with clinical improvement of atopic dermatitis patients by immunotherapy

Although immunotherapy is not accepted as a curative treatment for atopic dermatitis (AD), most studies have shown positive effects of immunotherapy on AD patients. The serum levels of CC chemokine ligand 17 (CCL17), CCL22 and CCL18 have been reported to be highly correlated with disease severity, which suggests important roles for CC chemokines in the pathogenesis of AD. Objective: The purpose of this study was to investigate the changes in clinical and immunologic markers before and after immunotherapy and to find which CC chemokines correlate with clinical improvement after immunotherapy with house dust mite (HDM) allergens in AD patients. Methods and Results: A total of 20 AD patients who were sensitized to HDM allergens through a skin-prick test and Pharmacia CAP system were treated with subcutaneous immunotherapy using HDM allergens (treatment duration 12-60 months). Eczema area and severity index scores in 20 patients with AD decreased significantly after immunotherapy (P < 0.001). Serum total immunoglobulin E (IgE) and Dermatophagoides pteronyssinus-specific IgE levels tended to decrease after treatment although this was not statistically significant, and the D. farinae-specific IgE level showed no change. Serum CCL17, CCL22 and CCL18 levels decreased significantly from baseline after treatment (P = 0.043, 0.017 and <0.001, respectively). The percentage reductions in serum CCL17 and CCL22 level were significantly correlated with reductions in disease severity (P = 0.007, R² = 0.301 and P = 0.037, R² = 0.177, respectively). Conclusion: We suggest that CCL17 and CCL22 are good immunological marker candidates that can be used to assess clinical improvement after immunotherapy in AD patients.