Graves’ disease (GD), an organ-specific autoimmune disease, is the most common cause of hyperthyroidism. Tumour necrosis factor-alpha (TNF-α) exhibits immunological and metabolic activities involved in the induction and maintenance of immune responses. We attempted to evaluate the relationship between GD and serum TNF-α and its soluble receptors (sTNFRs), soluble TNF receptor 1 and 2 (sTNF-R1 and sTNF-R2). A total of 72 GD patients and 72 matched healthy individuals were recruited for this study. Serum TNF-α and sTNFRs were measured by sandwich ELISA. In our study, no significant difference was observed in TNF-α, but sTNFRs were found to be significantly elevated in GD patients compared to healthy individuals. Serum sTNFR levels were positively correlated with free triiodothyronine (FT3) and free thyroxine (FT4), and TNF-α was negatively correlated with thyroid-stimulating hormone (TSH) in the GD group. It was also shown that thyrotropin receptor antibody (TRAb) was positively correlated with TNF-α and sTNFRs. Spearman’s correlation analysis showed that only sTNF-R1 was positively correlated with complement C3. Multiple linear regression analysis suggests that serum levels of sTNF-R1 and FT4 may play an important role in the serum level of FT3. According to the median value of FT3 level, GD patients were further divided into a high FT3 group and a low FT3 group. The serum levels of sTNF-R1 in the high FT3 GD group were significantly higher than those in the low FT3 GD group. In conclusion, sTNFRs may play an important role in anti-inflammatory and immune response in GD.
Qing Zhu, Jianbin Su, Xueqin Wang, Mengjie Tang, Yingying Gao and Dongmei Zhang
Yun Hu, Na Li, Peng Jiang, Liang Cheng, Bo Ding, Xiao-Mei Liu, Ke He, Yun-Qing Zhu, Bing-li Liu, Xin Cao, Hong Zhou and Xiao-Ming Mao
Thyroid nodules are usually accompanied by elevated thyroglobulin (Tg) level and autoimmune thyroid diseases (AITDs). However, the relationship between Tg and AITDs is not fully understood. Dysfunction of regulatory T cells (Tregs) plays an important role in the development of AITDs. We aimed to evaluate the effects of Tg on the function of Tregs in patients with thyroid nodules.
Tg levels and the functions of Tregs in peripheral blood and thyroid tissues of patients with thyroid nodules from Nanjing First Hospital were evaluated. The effects of Tg on the function of Tregs from healthy donors were also assessed in vitro. The function of Tregs was defined as an inhibitory effect of Tregs on the effector T cell (CD4+ CD25− T cell) proliferation rate.
The level of Tg in peripheral blood correlated negatively with the inhibitory function of Tregs (R = 0.398, P = 0.03), and Tregs function declined significantly in the high Tg group (Tg >77 μg/L) compared with the normal Tg group (11.4 ± 3.9% vs 27.5 ± 3.5%, P < 0.05). Compared with peripheral blood, the function of Tregs in thyroid declined significantly (P < 0.01), but the proportion of FOXP3+ Tregs in thyroid increased (P < 0.01). High concentration of Tg (100 μg/mL) inhibited the function of Tregs and downregulated FOXP3, TGF-β and IL-10 mRNA expression in Tregs in vitro.
Elevated Tg level could impair the function of Tregs, which might increase the risk of AITDs in patient with thyroid nodules.