初发未治的Graves病患者血清IgG对鼠甲状腺细胞内钙离子的作用

THE EFFECT OF IGGS FROM UNTREATED GRAVES′DISEASE PATIENT ON CYTOSOLIC Ca^(2+) OF RAT THYROID FRTL-5 CELLS

为研究初发未治的Graves病患者血清IgG对大鼠甲状腺细胞 (FRTL 5 )内Ca2 + 的作用 ,将Graves病患者血清IgG分为甲状腺刺激抗体 (TSAb)阴性和阳性两组 ,比较正常人、TSAb阴性和阳性IgG对FRTL 5细胞内Ca2 + 的作用。结果发现 :(1) 80 .6 % (2 9/36 )初发未治的Graves病患者TSAb阳性 ,19.4% (7/36 )TSAb阴性 ;(2 )不同浓度 (0 .1～ 1mg/ml)的TSAb阳性IgG对FRTL 5细胞内Ca2 + 均有明显刺激作用 ,并呈现浓度依赖性 ;(3)高浓度 (1mg/ml)的TSAb阴性IgG对细胞内Ca2 + 也有刺激作用 ,且Ca2 + 的变化时相与TSAb阳性IgG作用于FRTL 5细胞时相类似 ;(4 )高浓度 (1mg/ml)的正常人IgG对FRTL 5细胞内Ca2 + 有一定程度的刺激作用 ,但Ca2 + 变化时相不同于Graves病IgG。提示部分Graves病患者血清IgG可同时激活AC/cAMP和PLC/Ca2 + 两种信号途径 ,推测这些血清IgG对细胞内Ca2 + 的刺激作用可能与其对AC的刺激作用有一定程度的相关性 ,因而Ca2 +

To investigate the effect of serum IgG from untreated Graves′ disease patient on the cytosolic Ca 2+ in FRTL 5 cells. The cultured FRTL 5 cells loaded with Ca 2+ probe Fluo 3 were stimulated with different concentrations of TSAb (thyroid stimulating antibody) positive or negative Graves′ IgGs and control IgGs respectively. The cytosolic Ca 2+ were observed by means of Laser Scanning Confocal Microscope (LSCM) followed by the stimulation of IgGs described. The results showed that the positive rate of serum TSAb was 80.6%(29/36). Cytosolic Ca 2+ levels in FRTL 5 cells could be increased by the TSAb positive Graves′ IgGs at different concentrations and in a dose dependent manner. High concentrations of both control IgGs and TSAb negative Graves′ IgGs were capable of increasing Ca 2+ in FRTL 5 cells, but the fluorescence changes were in different patterns. These results suggest that untreated Graves′ IgGs are able to stimulate both AC/cAMP and PLC/ Ca 2+ signal transduction pathway in FRTL 5 cells, and the effect on the Ca 2+ pathway is related to that on the cAMP pathway in certain extent by the Graves′ IgGs. The Ca 2+ response to Graves′ IgG preparations may be utilized as a functional marker to evaluate the titers of TSAb for Graves′ disease.