The role of heterodimer IL 17A/F in atopic dermatitis

Introduction
The importance of multifactorial dysregulation in immune response is well recognised in atopic dermatitis (AD). Th17 family cytokine IL-17 (IL-17A-F) is of significance in both acute and chronic phase of AD.

Aim
We analysed the differences between serum levels of IL-17A/F and IL-17A, IL-17-F, IL-13, IL-4, association of rs2275913 IL-17A and rs763780 IL-17F gene polymorphisms in paediatric AD patients and control subjects.

Material and methods
We assessed 30 children with AD and 30 healthy patients aged 2–12 years. Eczema Area and Severity Index, Investigator Global Assessment and Scoring Atopic Dermatitis scales were used to analyse the severity of skin lesions in AD patients. Genotyping was performed using PCR and the serum concentrations of IL-17A/F, IL-17A, IL-17F, while IL-13 and IL-4 interleukins were determined by enzyme-linked immuno-sorbent assays (ELISA).

Results
The revised median assessment scoring in disease severity showed that the studied AD population had a moderate course of the disease. The obtained results indicated elevated plasma levels of IL-17A/F and IL-17-13 in AD patients with no statistically significance of IL-17A, IL-17F and IL-4 compared to controls. AD duration was positively correlated with IL-13 levels and negatively with IL-17A/F (p < 0.05). Moreover, there was no significant difference between case and control groups in the frequency of genotypes and alleles at rs2275913 IL-17A and rs763780 IL-17F polymorphisms (p > 0.05).

Conclusions
This study demonstrates increased levels of IL-17A/F in atopic patients, which is positively correlated with severity of the disease and the early phase of the disease. These results highlight a functional role of this cytokine in the pathogenesis of AD in paediatric patients.