Expression of miRNA 155, FOXP3 and ROR gamma, in children with moderate and severe atopic dermatitis
Massimiliano Bergallo, Martina Accorinti, Ilaria Galliano, Paola Coppo, Paola Montanari, Pietro Quaglino, Francesco Savino
Abstract
BACKGROUND: Atopic dermatitis is a disease characterized by a chronic inflammatory process in the skin, but its link to miRNA 155 is less known. The aim of the study was to evaluate the expression of microRNA155, and T helper type 17 cells and Treg cells in children with atopic dermatitis. METHODS: The study population consisted of: children seen for atopic dermatitis at the outpatient ambulatory of Dermatology at the Children Hospital Regina Margherita, Torino, Italy (N.=23); healthy control subjects (N.=23). Blood samples were taken during routine control analysis and the expression of miRNA 155 and the production of FOXP3 and RORγ was determined using PCR real time. RESULTS: The analysis of miR-155 shows that the over-expression of miR-155 is statistically significant (P=0.0040) in the group of patients with atopic dermatitis compared to the healthy control group. Analysis of mRNAs of FOXP3 and RORγ shows a FOXP3 mRNA expression statistically higher in the group of patients (P=0.0057). The Th17 / Treg ratio is significantly smaller in patients with atopic dermatitis (P=0.0012). Also the ratio miR-155/Th17/Treg is larger in the group of patients with atopic dermatitis (P=0.0002). CONCLUSIONS: Our results suggest that increased miR-155 and FOXP3 and RORγ responses may provide a link to immune dysregulation associated with atopic dermatitis. Although a point-by-point correlation between miR-155 and the ratio Th17/Treg is not demonstrated, our findings shows that these two elements do not appear to be completely unrelated to each other.