Zhao Shu-jun, Sun Fu-jun, Tian En-jiang, Chen Zu-pei
Institute of Endocrinology, Tianjin Medical University, Tianjin 300070, China.
Zhonghua Yu Fang Yi Xue Za Zhi. 2006 Jan;40(1):18-20.
To observe the effects of iodine on the level of CD4/CD8 cells and the production of thyroglobulin autoantibody (TGAb) and thyroid peroxidase autoantibody (TPOAb) in Wistar rats and to investigate the role of iodine in thyroid autoimmunity.
Rat models with different iodine intakes including low iodine (LI,), normal iodine (NI,), 5 times normal iodine (5HI), 10 times normal iodine (10HI), 50 times normal iodine (50HI) and 100 times normal iodine (100HI) were established. The amount of iodine intake per rat per day in every group was about < 1, 6.15, 30.75, 61.50, 307.50, 615.00 microg separately. The levels of CD4 and CD8 immune cells in peripheral blood were measured by using flow cytometry. Radioimmunoassay (RIA) was used to determine the titers of TGAb and TPOAb in the serum.
In peripheral blood, the level of CD4 cells in LI group was (57.9 +/- 4.3)%, being much higher than in NI group (51.2 +/- 4.9)%. When the level of CD8 cells in 100HI group was (18.4 +/- 3.1)% showing significantly lower than in NI group (26.5 +/- 4.1)%, thus making the ratio of CD4/CD8 cells in the above two groups (LI: 2.4 +/- 0.40 and 100 HI: 2.7 +/- 0.4) higher than in NI group (1.9 +/- 0.3). As comparing with NI group (2099 +/- 220) CPM, the level of TGAb in LI group (1510 +/- 221) CPM was significantly decreased; while in 50HI group (3986 +/- 286) and 100HI group (3550 +/- 378) CPM, the levels of TGAb were both increased, and the levels of TPOAb in 10HI group (2066 +/- 184) CPM and in 50HI group (2141 +/- 163) CPM were both distinctly lower than in NI group (2372 +/- 245) CPM.
Iodine might exert influence on the level of CD4/CD8, and thus the production of thyroid antibodies might directly or indirectly take part in the process of thyroid autoimmunity. Both low iodine and 100 times normal iodine intakes might activate the immune state on some degrees. The effects of iodine on immune responses of TG and TPO antigen in thyroid autoimmunity might not be completely the same.
观察碘对Wistar大鼠CD4/CD8细胞水平及甲状腺球蛋白自身抗体（TGAb）和甲状腺过氧化物酶自身抗体（TPOAb）产生的影响，探讨碘在甲状腺自身免疫中的作用。
建立不同碘摄入量的大鼠模型，包括低碘（LI）、正常碘（NI）、5倍正常碘（5HI）、10倍正常碘（10HI）、50倍正常碘（50HI）和100倍正常碘（100HI）。每组大鼠每天的碘摄入量分别约为<1、6.15、30.75、61.50、307.50、615.00微克。采用流式细胞术检测外周血中CD4和CD8免疫细胞水平。用放射免疫分析法（RIA）测定血清中TGAb和TPOAb的滴度。
外周血中，LI组CD4细胞水平为（57.9±4.3）%，显著高于NI组（51.2±4.9）%。100HI组CD8细胞水平为（18.4±3.1）%，显著低于NI组（26.5±4.1）%，使得上述两组的CD4/CD8细胞比值（LI：2.4±0.40和100HI：2.7±0.4）高于NI组（1.9±0.3）。与NI组（2099±220）CPM相比，LI组TGAb水平（1510±221）CPM显著降低；而50HI组（3986±286）CPM和100HI组（3550±378）CPM的TGAb水平均升高，10HI组（2066±184）CPM和50HI组（2141±163）CPM的TPOAb水平均明显低于NI组（2372±245）CPM。
碘可能对CD4/CD8水平产生影响，进而甲状腺抗体的产生可能直接或间接参与甲状腺自身免疫过程。低碘和100倍正常碘摄入量在一定程度上都可能激活免疫状态。碘在甲状腺自身免疫中对TG和TPO抗原免疫反应的影响可能并不完全相同。
