Kasuga Y, Matsubayashi S, Sakatsume Y, Akasu F, Jamieson C, Volpé R
Department of Medicine, Wellesley Hospital, University of Toronto, Ontario.
Clin Invest Med. 1991 Aug;14(4):277-81.
We have attempted to determine whether xenotransplanted human thyroid tissue into nude mice would act as a physiological substitute for the mouse thyroid gland after the mice had been rendered hypothyroid, using radioactive iodine (131I). The dosage of 0.2 millicuries of 131I was given to each mouse. The xenotransplantations of human thyroid tissue, i.e., normal, Graves' and nontoxic multinodular goitre, were carried out three weeks after radioactive ablation. The values of TSH in all mice rose to high levels (71 +/- 15.6 ng/ml, +/- SD) by three weeks after 131I administration. The TSH values in the mice declined rapidly and reached normal levels by 3-5 weeks after xenotransplantation. In addition, the serum T4 values were generally in the euthyroid range by 3-6 weeks after xenotransplantation. There were no marked differences in the changes of serum T4 and TSH when the three groups were compared. These results indicated that the xenografted human thyroid tissue permitted a return to a normal feedback system as reflected by normal serum TSH and T4 values in the animals. The Graves' thyroid tissue reverted to normal physiological function when removed from its human (abnormal) immune environment, signifying that Graves' thyrocytes are mere passive captives to immune events. This model should prove to be useful in the study of human thyroid physiology and pathophysiology.
我们试图确定，在使用放射性碘（131I）使裸鼠甲状腺功能减退后，将人甲状腺组织异种移植到裸鼠体内是否能起到替代小鼠甲状腺的生理作用。给每只小鼠注射0.2毫居里的131I。在放射性消融三周后，进行人甲状腺组织的异种移植，即正常甲状腺组织、格雷夫斯病甲状腺组织和非毒性多结节性甲状腺肿组织。在给予131I后三周，所有小鼠的促甲状腺激素（TSH）值均升至高水平（71±15.6纳克/毫升，±标准差）。在异种移植后3至5周，小鼠的TSH值迅速下降并达到正常水平。此外，在异种移植后3至6周，血清甲状腺素（T4）值一般处于甲状腺功能正常范围内。比较这三组时，血清T4和TSH的变化没有明显差异。这些结果表明，异种移植后的人甲状腺组织能使动物恢复正常的反馈系统，这可从动物正常的血清TSH和T4值反映出来。当格雷夫斯病甲状腺组织脱离其人体（异常）免疫环境时，会恢复正常生理功能，这表明格雷夫斯病甲状腺细胞仅仅是免疫事件的被动受害者。该模型在人类甲状腺生理学和病理生理学研究中应会被证明是有用的。
