The Role of age on induction and continuity of autoimmune thyroiditis

以小鼠实验性自身免疫性甲状腺炎(EAT)为模型，对小鼠甲状腺炎症的严重程度和抗小鼠甲状腺球蛋白(MTG)抗体的形成进行了18个月的长期观察。在EAT敏感株(CBA、C3H)中，甲炎的严重性和MTG抗体的产生都持续了很长时间。在耐受性小鼠(BALB/c)中，甲状腺炎症仍然很轻微，对MTG的低抗体反应变得可以忽略不计。血清中针对绵羊红细胞(SRBC)的抗体也持续了很长时间，这取决于小鼠的品系。另一方面，衰老对易感小鼠的EAT诱导作用有显著影响，MTG抗体反应和甲状腺浸润率均显著降低。这些数据与针对SRBC的抗体形成减少有很好的相关性。在刀豆蛋白A刺激细胞的过继转移中，进一步比较了幼鼠和老年鼠作为供体或受体的情况。来自年轻或老年MTG免疫小鼠的淋巴结细胞将明显的甲状腺炎转移到正常的年轻和老年受体小鼠。然而，同样处理的MTG免疫老年小鼠的脾细胞对有丝分裂原或MTG的体外刺激反应较差，并将甲状腺炎转移给极少数正常的年轻或老年小鼠。在下一次实验中，应进行针对甲状腺上皮细胞的效应性T细胞的克隆。此外，应研究体内免疫系统在注射克隆效应性T细胞后的反应。

After induction of experimental autoimmune thyroiditis (EAT) in mice, long-term observation on both the severity of thyroiditis and antibody formation against mouse thyroglobulin (MTg) was carried out over a period of 18 months. Both the severity of thyroiditis and MTg antibody production continued for a long term in EAT-susceptible strains (CBA, C3H). In EAT-resistant mice (BALB/c), thyroiditis remained minimal, if present, and the low antibody response to MTg became negligible. Antibody against sheep red blood cells (SRBC) in serum, also continued for a long term, depending on mouse strains. On the other hand, aging had a prominent effect on the EAT induction in susceptible mice; both MTg antibody response and thyroid infiltration were markedly reduced. These data were well correlated with reduced antibody formation against SRBC. Young and old mice were further compared as donors or recipients in adoptive transfer of concanavalin A-stimulated cells. Lymph node cells from either young or old MTg-immunized mice transferred appreciable thyroiditis to normal young and old recipient mice. However, similarly treated spleen cells from MTg-immunized old mice responded more poorly to in vitro stimulation with mitogens or MTg and transferred thyroiditis to very few normal young or old mice.In next experiment, cloning of effector T cells against thyroid epithelial cells should be performed. Further, the response of in vivo immune system should be studied after injection of cloned effector T cells.