Eosinophilia triggers changes in IL-5, eotaxin and IL-17, and acts as a prognostic biomarker for atopic dermatitis

Purpose: To investigate the implication of eosinophilia in atopic dermatitis (AD).
Methods: A total of 139 AD patients from The First Affiliated Hospital of Guangxi University of Chinese Medicine between February 2013 and May 2015, were involved in this study. Scoring atopic dermatitis (SCORAD) index was used to evaluate the skin lesions. The levels of IL-4, IL-5, IL-13, IL-17, INF-gamma, IP-10, eotaxin and Regulated on Activation, Normal T-cell Expressed and Secreted (RANTES), were determined with commercial enzyme-linked immunosorbent assay (ELISA) kits. Eosinophil counts were carried out by granulocyte count method. Correlation between SCORAD scores and levels of cytokines was analyzed using the Spearman correlation method.
Results: SCORAD scores significantly increased in the eosinophil-positive group when compared to eosinophil-negative group (p < 0.05). Eosinophil counts correlated with SCORAD scores in the eosinophil-positive group (p < 0.05). INF-γ, IP-10 and RANTES levels were significantly higher in the eosinophil-positive group than in eosinophil- negative group, while IL-5, eotaxin and IL-17 levels significantly decreased in eosinophil-positive group (p < 0.05). In the eosinophil-positive group, IL-5, eotaxin and IL-17 levels positively correlated with SCORAD scores.
Conclusion: Eosinophilia triggers lL-5, eotaxin and IL-17 changes and acts as a prognostic biomarker for atopic dermatitis. These findings may give further insights into the pathogenesis of AD.