The follicles are the minimal functional unit of the thyroid; the morphology and the function of each follicle can vary significantly. However, the reasons for the apparent follicular heterogeneity are poorly understood. Some tissue-resident regulatory T cells (Tregs) have a special phenotype that expresses unique molecules related to local tissue and regulates the tissue functions. The aim of this study was to identify the phenotype of thyroid Tregs and the roles of thyroid Tregs in thyroid physiological regulation. Thyroid tissue and peripheral blood samples were obtained from patients with benign thyroid nodules. Microarray-based gene expression, flow cytometry, immunofluorescence microscopy, and functional analysis of thyroid Tregs were performed. Here, we demonstrated that human thyroid Tregs expressed high level of thyroglobulin (Tg), both gene and protein. The immunofluorescence microscopy of thyroid section showed that the FOXP3+Tg+ cells concentrated in some of the thyroid follicles, at the side of the thyroid follicle. The peripheral blood Tregs expressed minimal levels of Tg, and low levels of Tg could effectively induce peripheral blood Tregs to express Tg, which was independent of thyrotropin simulation. Furthermore, the Tg secreted freely from thyroid Tregs that negatively regulated some thyroid-related genes expression. Our results revealed that the thyroid Tregs was a distinct population of Tregs, which expressed high level of Tg. The thyroid Tregs regulate thyroid function by Tg that is paracrine from the cells.
Yun-Qing Zhu, Yun Hu, Ke He, Na Li, Peng Jiang, Yu-Qin Pan, Hong Zhou and Xiao-Ming Mao
Kamran Ullah, Tanzil Ur Rahman, Hai-Tao Pan, Meng-Xi Guo, Xin-Yan Dong, Juan Liu, Lu-Yang Jin, Yi Cheng, Zhang-Hong Ke, Jun Ren, Xian-Hua Lin, Xiao-Xiao Qiu, Ting-Ting Wang, He-Feng Huang and Jian-Zhong Sheng
Previous studies have shown that increasing estradiol concentrations had a toxic effect on the embryo and were deleterious to embryo adhesion. In this study, we evaluated the physiological impact of estradiol concentrations on endometrial cells to reveal that serum estradiol levels probably targeted the endometrium in controlled ovarian hyperstimulation (COH) protocols. An attachment model of human choriocarcinoma (JAr) cell spheroids to receptive-phase endometrial epithelial cells and Ishikawa cells treated with different estradiol (10−9 M or 10−7 M) concentrations was developed. Differentially expressed protein profiling of the Ishikawa cells was performed by proteomic analysis. Estradiol at 10−7 M demonstrated a high attachment rate of JAr spheroids to the endometrial cell monolayers. Using iTRAQ coupled with LC–MS/MS, we identified 45 differentially expressed proteins containing 43 significantly upregulated and 2 downregulated proteins in Ishikawa cells treated with 10−7 M estradiol. Differential expression of C3, plasminogen and kininogen-1 by Western blot confirmed the proteomic results. C3, plasminogen and kininogen-1 localization in human receptive endometrial luminal epithelium highlighted the key proteins as possible targets for endometrial receptivity and interception. Ingenuity pathway analysis of differentially expressed proteins exhibited a variety of signaling pathways, including LXR/RXR activation pathway and acute-phase response signaling and upstream regulators (TNF, IL6, Hmgn3 and miR-140-3p) associated with endometrial receptivity. The observed estrogenic effect on differential proteome dynamics in Ishikawa cells indicates that the human endometrium is the probable target for serum estradiol levels in COH cycles. The findings are also important for future functional studies with the identified proteins that may influence embryo implantation.