Th17 cell plays a role in the pathogenesis of Hashimoto's thyroiditis in patients

Clin Immunol. 2013 Dec;149(3):411-20. doi: 10.1016/j.clim.2013.10.001. Epub 2013 Oct 11.


Hashimoto's thyroiditis (HT) has long been epidemiologically associated with excess iodine levels. However, the underlying immunological mechanisms still remain largely unexplored. Th17 cells are commonly recognized as playing vital roles in various autoimmune diseases. Here we show that intra-thyroid infiltrating Th17 cells and serum IL-17 levels were significantly increased in HT patients. However, the concentration of serum IL-17 was inversely correlated with patients' residual thyroid function while the heterogeneously expressed thyroid IL-17 was directly correlated with local fibrosis. Administration of moderate high levels of iodine was found to facilitate the polarization of murine splenic naïve T cells into Th17 cells, whereas extreme high levels of iodine favored Th1 polarization and inhibited Treg development. These findings suggest that both Th1 and Th17 cells may be involved in the pathogenesis of HT and high levels of iodine may play a critical role in this process by modulating T cell differentiation.

Keywords: Autoimmune thyroiditis; Hashimoto's thyroiditis; IL-17; Iodine; Regulatory T cell; Th17 cell.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Animals
  • Case-Control Studies
  • Cell Differentiation / drug effects
  • Cell Movement / drug effects
  • Female
  • Fibrosis
  • Hashimoto Disease / blood
  • Hashimoto Disease / immunology
  • Hashimoto Disease / pathology*
  • Humans
  • Interleukin-17 / biosynthesis
  • Interleukin-17 / blood
  • Interleukin-17 / immunology*
  • Iodine / pharmacology
  • Male
  • Mice
  • Middle Aged
  • Organ Specificity
  • Spleen / immunology
  • Spleen / metabolism
  • Spleen / pathology
  • Th1 Cells / immunology
  • Th1 Cells / metabolism
  • Th1 Cells / pathology*
  • Th17 Cells / immunology
  • Th17 Cells / metabolism
  • Th17 Cells / pathology*
  • Thyroid Gland / immunology
  • Thyroid Gland / metabolism
  • Thyroid Gland / pathology*


  • Interleukin-17
  • Iodine