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Objective Through detecting the expression of chemokine CCL21 and its receptor CCR7 in thyroiditis of NOD mice induced by excessive iodine and thyroglobulin (Tg) immunization,to explore the mechanism of lymphocytic infiltration.Methods Seven to eight weeks old female NOD (non-obese diabetic) mice were used,the mice were divided into four groups by random number table,7 mice for each group.Control group:intoke distilled water;,Tg group:intoke'distilled water,use pig Tg emulsified in Freund's complete adjuvant subcutaneous injection to immunization,0.10 mg Tg for each mouse at 8 weeks old,strengthened immunity at 11 and 15 weeks old (0.05 mg Tg for each mouse,and emulsified by Freund's incomplete adjuvant); iodine excess (HI) group:intoke 0.05％ NaI water; iodine excess combined with Tg (HI + Tg) group:intoke 0.05％ NaI water,Tg immunization method was same to Tg group; all mice were raised in specific pathogen free (SPF) environment.All mice were executed at 16 weeks old,and removed the thyroid tissue.Morphologic change in thyroid was observed by HE staining.Immunofluorescence (IF) staining was used to observe CD3,CD22,CCL21 and CCR7 expression in thyroid.Real-time PCR was used to detect CCL21 mRNA expression in thyroid.Results The morphologic change of thyroid was observed under the light microscope,in HI group,thyroid follicle distended,colloid accumulation,lymphocytes accumulate together and disorganization was seen; Tg group thyroid had scatted lymphocytes; HI + Tg group enhanced inflammation response and disorganization.IF staining showed that lymphocytes infiltrated in thyroid were almost CD3+ T cells,only few scatted CD22+ B cells; CCL21 and CCR7 were negative in control group,CCR7 positive cells were scatted in Tg group but no CCL21 expression,in HI and HI + Tg groups,we could see CCL21 strong positive expression in inflammation area and also had CCR7 positive cells there.CCL21 mRNA relative expression in thyroid:Tg group (3.20 ± 0.18),HI group (1.72 ± 0.31),and HI ± Tg group (9.94 ± 0.32) increased compared to control group (1.00 ± 0.17,all P ＜ 0.01).Conclusion CCL21 and its receptor CCR7 have improved lymphocytic infiltration in autoimmune thyroiditis
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AIM: To investigate the effects of poly (I:C) as virus mimics on iodine excess-induced chronic lymphocytic thyroiditis in NOD mouse. METHODS: Female, 32 NOD mice were randomly divided into 4 groups: (1) control;(2) high iodine;(3) poly (I:C);(4) high iodine+poly (I:C). Nine weeks after administration, mice were sacrificed. The following parameters were determined: body weight, thyroid weight and anatomic form. Thyroid hormone (T_4) in serum was measured by radioimmunoassay, the thyroid morphology was observed through HE staining, apoptosis was detected by TUNEL, the mRNA expression levels of TRAIL, TRAIL-sR1, ICAM-1 and CXCL10 were determined by the method of real time RT-PCR. RESULTS: Compared to control group and poly (I:C) group, the thyroid absolute weight and relative weight in high iodine group were increased (P<0.01), the level of total T_4 in serum was decreased (P<0.05), inflammation and apoptosis were obviously observed, the mRNA expressions of TRAIL, TRAIL-sR1, CXCL10 and ICAM-1 were upregulated (P<0.05). Compared to high iodine group, thyroid absolute weight and relative weight in high iodine+poly (I:C) group were further increased, the level of total T_4 in serum was further decreased (P<0.05), the ratio of inflammatory degree Ⅳ increased to 50.0%, the numbers of apoptosis cells were further enhanced, the mRNA expressions of TRAIL, TRAIL-sR1, ICAM-1 and CXCL10 were further upregulated (P<0.05). Otherwise, the tendency of all parameters in poly (I:C) group was similar to that in control group (P>0.05). CONCLUSION: Poly (I:C) aggravates chronic lymphocytic thyroiditis induced by excess of iodine associated with increase in infiltration of lymphocytes and induction of apoptosis.
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Objective To observe the pathological characteristics of thyroiditis induced by iodine excess and thyroglobulin (Tg) immunization and to explore the mechanism of thyroiditis induced by iodine excess. Methods NOD mice were used for intaking 0.05% Nal water and(or) Tg immunization. Morphologic change in thyroid and apoptosis were observed. The levels of serum TT4, TSH, thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb) were measured. Responding to Tg, lymphocytic proliferation of lymph node and spleen, interleukin-4(IL-4)and γ-interferon(IFN-γ) levels in culture medium of splenocytes were detected. Real-time PCR Was used to detect mRNA expressions of IL-4, IFN-γ, chemokine ligand 10 (CXCL10) and intercellular adhesion molecular-1(ICAM-1) in thyroid. Results Distended thyroid follicles,colloid accumulation, intense lymphocytic infiltration and disorganization were seen in thyroid of iodine excess group, along with increased apoptosis of thyroid cells(34.66～ 2.78 vs 5.11±0.62 ,P<0.01). The levels of TT4 were lowered while TSH raised ,but no production of thyroid-specific autoantibodies was revealed. Lymph node and spleen cells showed positive respornse under stimulation of Tg. The level of IFN-γ[(1. 272±0.049 vs 1. 139±0. 025)ng/L,P<0. 01] was raised in culture medium of splenocytes but not IL-4. The expression of IFN-γ, CXCLI0 and ICAM-1 mRNA were increased in thyroid. But in Tg group, some lymphocytes were scattered in thyroid, autoantibodies emerged ,and the level of IL-4 was increased in cuhure medium of splenocytes[(18. 508±0. 113 vs 13. 368±0. 016)ng/L, P<0. 01]. ledine excess combined with Tg enhanced these inflammatory reaction. Conclusion Iodine excess induced thyroiditis in NOD mice. The process seems to be Th1 response dominant organ-specific autoimmune diseases. Iodine excess and Tg immunizatiou play a synergistic role in inducing experimental autoimmune thyroiditis.
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AIM:To investigate the effects of poly (I:C) as virus mimics on iodine excess-induced chronic lymphocytic thyroiditis in NOD mouse. METHODS:Female,32 NOD mice were randomly divided into 4 groups:(1) control; (2) high iodine; (3) poly (I:C); (4) high iodine+poly (I:C). Nine weeks after administration,mice were sacrificed. The following parameters were determined:body weight,thyroid weight and anatomic form. Thyroid hormone (T4) in serum was measured by radioimmunoassay,the thyroid morphology was observed through HE staining,apoptosis was detected by TUNEL,the mRNA expression levels of TRAIL,TRAIL-sR1,ICAM-1 and CXCL10 were determined by the method of real time RT-PCR. RESULTS:Compared to control group and poly (I:C) group,the thyroid absolute weight and relative weight in high iodine group were increased (P0.05). CONCLUSION:Poly (I:C) aggravates chronic lymphocytic thyroiditis induced by excess of iodine associated with increase in infiltration of lymphocytes and induction of apoptosis.