Increased Levels of Serum Interleukin-17 in Patients with Hashimoto's Thyroiditis

BACKGROUND: CD4+ T-cells play important roles in the pathogenesis of Hashimoto's thyroiditis (HT). However, there is limited data about characteristics and function of the newly interleukin (IL)-17–producing T-helper cells in this common autoimmune thyroid disorder. AIM: The purpose of this study was to assess the levels of T-helper 17-related cytokines in sera of patients with HT. MATERIALS AND METHODS: Cytokine concentrations were measured in 48 patients with overt (n = 23) and subclinical hypothyroidism (25) and 35 healthy controls using enzyme-linked immunosorbent assay. RESULTS: The serum levels of IL-17 were significantly higher in patients than controls (P = 0.001) while no differences were observed with regard to levels of IL-22 and IL-23 between patients and normal controls. CONCLUSION: These results suggest that IL-17 could play some role in the pathogenesis of HT.