Chen Xia, Chen Hui
Department of Endocrinology and Metabolism, The Second Hospital and Clinical Medical School, Lanzhou University, Lanzhou, Gansu 730000, P.R. China.
Mol Med Rep. 2025 Oct;32(4). doi: 10.3892/mmr.2025.13639. Epub 2025 Aug 1.
Thyroid function is regulated in a substantial manner by thyroid‑stimulating hormone receptor (TSHR), and aberrant alterations in thyroid function are triggered by the interaction of TSHR with its antibodies, thyroid‑stimulating hormone receptor antibodies (TRAb). The expression, immunogenicity and clinical significance of fusion proteins comprising different structural domains of TSHR were investigated. Fusion proteins containing several human TSHR (hTSHR) structural domains were created. experiments utilized these fusion proteins as antigens to specifically bind and analyze patient sera using an ELISA. To investigate the immunogenicity and clinical significance of various structural domains of TSHR, experiments included immunizing BALB/c mice with various fusion proteins of hTSHR, measuring serum autoantibodies, assessing thyroid function, performing histological examination and using flow cytometry to identify changes in T cell subsets. Three distinct hTSHR fusion protein fragments (hTSHR289, hTSHR290 and hTSHR410) were synthesized. The hTSHR290 fusion protein demonstrated the highest binding reaction with TRAb sera from patients with hypothyroidism, and the hTSHR289 fusion protein demonstrated considerable specific binding reactivity with stimulating antibodies, as observed in sera from patients with hyperthyroidism. Pathological alterations associated with hyperthyroidism were observed in mice in the hTSHR289 fusion protein group, while pathological changes associated with hypothyroidism were observed in mice in the hTSHR290 fusion protein group. Immunized BALB/c mice exhibited increased levels of CD4 T cell subsets, and decreased levels of CD8CD122 and CD4CD25 T cell subsets. Fusion proteins of different structural domains of TSHR exhibited varying immunogenicity. The hTSHR289 fusion protein and hTSHR290 fusion protein prepared in the present study could serve as a basis for the development of ELISA kits for the detection of thyroid‑stimulating immunoglobulins and TSHR‑blocking antibodies. Fusion proteins of different structural domains of TSHR induced clinical symptoms of hyperthyroidism and hypothyroidism in mice. The present study provides a scientific basis for future studies on the etiology and mechanisms of autoimmune thyroid diseases, as well as the invention of novel methods for TRAb detection.
甲状腺功能在很大程度上受促甲状腺激素受体（TSHR）调节，甲状腺功能的异常改变是由TSHR与其抗体促甲状腺激素受体抗体（TRAb）相互作用引发的。研究了包含TSHR不同结构域的融合蛋白的表达、免疫原性及临床意义。构建了含几个人类TSHR（hTSHR）结构域的融合蛋白。实验利用这些融合蛋白作为抗原，通过酶联免疫吸附测定（ELISA）特异性结合并分析患者血清。为研究TSHR不同结构域的免疫原性及临床意义，实验包括用hTSHR的各种融合蛋白免疫BALB/c小鼠、检测血清自身抗体、评估甲状腺功能、进行组织学检查以及用流式细胞术鉴定T细胞亚群的变化。合成了三种不同的hTSHR融合蛋白片段（hTSHR289、hTSHR290和hTSHR410）。hTSHR290融合蛋白与甲状腺功能减退患者血清中的TRAb显示出最高的结合反应，hTSHR289融合蛋白与刺激抗体显示出相当的特异性结合反应，如在甲状腺功能亢进患者血清中观察到的那样。hTSHR289融合蛋白组小鼠出现了与甲状腺功能亢进相关的病理改变，而hTSHR290融合蛋白组小鼠出现了与甲状腺功能减退相关的病理变化。免疫后的BALB/c小鼠CD4 T细胞亚群水平升高，CD8CD122和CD4CD25 T细胞亚群水平降低。TSHR不同结构域的融合蛋白表现出不同的免疫原性。本研究制备的hTSHR289融合蛋白和hTSHR290融合蛋白可为开发检测促甲状腺免疫球蛋白和TSHR阻断抗体的ELISA试剂盒奠定基础。TSHR不同结构域的融合蛋白在小鼠中诱发了甲状腺功能亢进和甲状腺功能减退的临床症状。本研究为未来自身免疫性甲状腺疾病的病因和机制研究以及TRAb检测新方法的发明提供了科学依据。
