Analysis of changes in expression of IL-4/IL-13/STAT6 pathway and correlation with the selected clinical parameters in patients with atopic asthma

Abstract

Introduction: Asthma is associated with activation of interleukin-4 (IL-4)/interleukin-13 (IL-13)/signal transducer and activator of transcription factor-6(STAT6) inflammatory response via overexpression of all pathway components: IL-4, IL-13, and STAT6. Objectives: To evaluate the association of IL-4, IL-13, and STAT6 expression and immunoexpression with atopic asthma development. Patients and methods: Fifty patients with atopic asthma and 20 healthy controls were enrolled into the study. Relative gene expression was analyzed by qPCR method. Immunoexpression was assessed by ELISA method. Results: The expression levels of IL-4, IL-13, and STAT6 were higher in patients compared to the controls, but a statistically significant difference was observed only for IL-13 ( P = 0.03). In immunoexpression analysis, a statistically significant difference between patients and controls was found for IgE ( P = 0.03). Significant positive correlations in the patient group were found between IL-13 gene expression and total level of serum IgE (rho = 0.230, P = 0.033), STAT6 gene/STAT6 protein and total level of serum IgE ( STAT6: rho = 0.077, P = 0.038; STAT6: rho = 0.049, P = 0.042), IL-4, and STAT6 expression (rho = 0.098, P = 0.048). Any significant correlations were found between expression/immunoexpression levels of the studied genes and clinical classification, clinical features, or lung function parameters. Conclusions: Our data support the role of Th2 cytokines (IL-4, IL-13) and STAT6 in Th1/Th2 imbalance and highlight the etiological relationship between IL-4/IL-13/STAT6 signaling and atopy and asthma.