Polymorphisms in Th17-related genes and the pathogenesis of autoimmune thyroid disease.

The prognosis of autoimmune thyroid disease (AITD) including Graves' disease (GD) and Hashimoto's disease (HD) is difficult to predict. We previously suggested that Th17 cells may be associated with the pathogenesis of AITD. However, the association between gene polymorphisms in Th17-related genes and the prognosis of AITD was not clarified.

Increases of the Th1/Th2 cell ratio in severe Hashimoto's disease and in the proportion of Th17 cells in intractable Graves' disease.

Background: T helper type 1 (Th1), Th2, and Th17 cells produce interferon (IFN)-gamma, interleukin (IL)-4, and IL-17A, respectively. We reported that IFN-gamma and IL-4 gene polymorphisms, which are related to higher IFN-gamma and lower IL-4 production, respectively, are more frequent in patients with severe Hashimoto's disease (HD) than in those mild HD. We now aim to investigate the proportion of peripheral Th1, Th2, and Th17 cells in patients with autoimmune thyroid disease (AITD).