Chen Kemin, Wei Yongzhong, Sharp Gordon C, Braley-Mullen Helen
Dept. of Internal Medicine, University of Missouri, M306 Medical Sciences, One Hospital Dr., Columbia, MO 65212, USA.
J Leukoc Biol. 2007 Jan;81(1):306-14. doi: 10.1189/jlb.0606402. Epub 2006 Oct 17.
Granulomatous experimental autoimmune thyroiditis (G-EAT) is induced in DBA/1 mice by adoptive transfer of mouse thyroglobulin (MTg)-primed spleen cells. TNF-alpha is an important proinflammatory cytokine and apoptotic molecule involved in many autoimmune diseases. To study its role in G-EAT, anti-TNF-alpha mAb was given to recipient mice. Disease severity was comparable between mice with or without anti-TNF-alpha treatment at days 19-21, the time of maximal severity of G-EAT, suggesting TNF-alpha is not essential for development of thyroid inflammation. However, thyroid lesions resolved at day 48 in anti-TNF-alpha-treated mice, while thyroids of rat Ig-treated controls had fibrosis. These results suggested that reducing TNF-alpha contributed to resolution of inflammation and inhibited fibrosis. Gene and protein expression of inflammatory molecules was examined by RT-PCR and immunostaining, and apoptosis was detected using TUNEL staining and an apoptosis kit. Thyroids of anti-TNF-alpha-treated controls had reduced proinflammatory and profibrotic molecules, e.g., IFN-gamma, IL-1beta, IL-17, inducible NOS and MCP-1, at day 19 compared with thyroids of rat Ig-treated mice. There were more apoptotic thyrocytes in rat Ig-treated controls than in anti-TNF-alpha-treated mice. The site of expression of the anti-apoptotic molecule FLIP also differed between rat Ig-treated and anti-TNF-alpha-treated mice. FLIP was predominantly expressed by inflammatory cells of rat Ig-treated mice and by thyrocytes of anti-TNF-alpha-treated mice. These results suggest that anti-TNF-alpha may regulate expression of proinflammatory cytokines and apoptosis in thyroids, resulting in less inflammation, earlier resolution, and reduced fibrosis.
通过转输用小鼠甲状腺球蛋白（MTg）致敏的脾细胞，在DBA/1小鼠中诱导出肉芽肿性实验性自身免疫性甲状腺炎（G-EAT）。肿瘤坏死因子-α（TNF-α）是一种重要的促炎细胞因子和凋亡分子，参与多种自身免疫性疾病。为了研究其在G-EAT中的作用，给受体小鼠注射抗TNF-α单克隆抗体（mAb）。在G-EAT严重程度最高的第19至21天，接受或未接受抗TNF-α治疗的小鼠疾病严重程度相当，这表明TNF-α对于甲状腺炎症的发展并非必不可少。然而，在第48天时，抗TNF-α治疗的小鼠甲状腺病变消退，而大鼠Ig治疗的对照小鼠甲状腺出现纤维化。这些结果表明，降低TNF-α有助于炎症消退并抑制纤维化。通过逆转录聚合酶链反应（RT-PCR）和免疫染色检测炎症分子的基因和蛋白表达，并使用末端脱氧核苷酸转移酶介导的缺口末端标记（TUNEL）染色和凋亡试剂盒检测凋亡情况。与大鼠Ig治疗的小鼠甲状腺相比，在第19天时，抗TNF-α治疗的对照小鼠甲状腺中促炎和促纤维化分子，如干扰素-γ（IFN-γ）、白细胞介素-1β（IL-1β）、白细胞介素-17、诱导型一氧化氮合酶（iNOS）和单核细胞趋化蛋白-1（MCP-1）减少。大鼠Ig治疗的对照小鼠中凋亡的甲状腺细胞比抗TNF-α治疗的小鼠更多。抗凋亡分子FLIP的表达位点在大鼠Ig治疗和抗TNF-α治疗的小鼠之间也有所不同。FLIP主要在大鼠Ig治疗的小鼠的炎症细胞中表达，而在抗TNF-α治疗的小鼠的甲状腺细胞中表达。这些结果表明，抗TNF-α可能调节甲状腺中促炎细胞因子的表达和凋亡，从而减少炎症、加速炎症消退并减少纤维化。
