IL4 and hypothyroidism: Guclu et al. [47] observed a significant decrease in serum IL-12 (one of the most important cytokines responsible for Th1-type cytokine responses), a statistically non-significant decrease in IFN-γ and no change in serum IL-2 or IL-4 in patients with hypothyroidism due to Hashimoto’s thyroiditis who underwent 12 weeks of LRT.