The cloning and sequencing of thyroid-stimulating hormone (TSH) receptor (TSHR), combined with advances in molecular techniques, have facilitated the understanding of the interaction of the TSHR antibodies (TSHRAbs) with the TSHR at the molecular level and have allowed the delineation of their clinical role. TSHRAbs in vivo are functionally heterogeneous; the stimulating TSHRAbs cause hyperthyroidism and diffuse goiter in patients with Graves' disease, whereas, the blocking TSHRAbs cause hypothyroidism in some patients with autoimmune hypothyroidism and are the cause of transient neonatal hypothyroidism. Measuring TSHRAbs has potential clinical implications in differential diagnosis of Graves' disease, predicting the outcome of Graves' disease after antithyroid drug treatment, and predicting the fetal/neonatal hyperthyroidism or neonatal hypothyroidism. The existence of epitope heterogeneity in a patient, i.e., of stimulating TSHRAbs with epitopes other than on the N-terminal region of the extracellular domain, is significantly associated with favorable long-term clinical response to antithyroid drug treatment. Measuring these subtypes for thyroid-stimulating antibody (TSAb) has potential clinical impli-cations, for example, in predicting responsiveness to treatment in untreated patients with Graves' disease.
Autoantibodies/*immunology ; Epitopes/immunology ; Graves Disease/diagnosis/immunology/therapy ; Humans ; Hyperthyroidism/diagnosis/*immunology/therapy ; Hypothyroidism/diagnosis/*immunology/therapy ; Immunoglobulins, Thyroid-Stimulating ; Receptors, Thyrotropin/*immunology

It has been reported that receptor-bound blocking type TSH receptor antibody (TRAb) can be converted to the stimulating type by anti-human IgG antibodies. To evaluate the relationship between the conversion of receptor-bound blocking type TRAb to the stimulating type and the biological activity of blocking type TRAb, we compared converting activities of blocking type TRAb from 10 patients with primary nongoitrous hypothyroidism with both the doses of blocking type TRAb which show 50% inhibition of 125I-bTSH binding to the TSH receptor and those which show 50% inhibition of TSH-stimulated cAMP production in cultured rat thyroid cells (FRTL-5). The additions of anti-human IgG antibody to FRTL-5 cell-bound blocking IgGs resulted in the increase in cAMP production in a dose-dependent manner and the converting activities (percent increase of cAMP production) also depended on the doses of blocking IgGs. The converting activities were significantly correlated with the doses of blocking IgGs which showed 50% inhibition of 125I-bTSH binding to the TSH receptor (r = 0.71, p = 0.011). And these converting activities were also significantly correlated with the doses of blocking IgGs which showed 50% inhibition of TSH-stimulated cAMP increase (r = 0.81, p = 0.002), and were negatively correlated with thyroid stimulation blocking antibody activities (r = 0.58, p = 0.02). We have demonstrated that all cell-bound blocking type TRAb were converted to the stimulating type by anti-human IgG antibody and the degree of conversion was negatively correlated with the biological activity of blocking type TRAb.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult ; Aged ; Antibodies/*immunology ; Autoantibodies/*immunology ; Binding, Competitive ; Female ; Humans ; Immunoglobulin G/*immunology ; Immunoglobulins, Thyroid-Stimulating ; Middle Aged ; Receptors, Thyrotropin/*immunology ; Thyroid Gland/*immunology

Animals ; Antibodies ; immunology ; therapeutic use ; Female ; Graves Disease ; immunology ; prevention & control ; Immune Tolerance ; immunology ; Mice ; Mice, Inbred BALB C ; Receptors, Thyrotropin ; immunology

PURPOSE: To investigate associations between serum thyroid stimulating hormone (TSH) receptor antibody (TRAb) levels and Graves' orbitopathy (GO) activity/severity in chronic-stage GO and compare the performance of two newly-developed TRAb assays (third-generation TSH-binding inhibition immunoglobulin [TBII] assay versus Mc4 thyroid-stimulating immunoglobulin [TSI] bioassay). METHODS: This study is a retrospective review of medical charts and blood tests from Korean GO patients who first visited the departments of ophthalmology and endocrinology, Yonsei University College of Medicine from January 2008 to December 2011, were diagnosed with GO and Graves' hyperthyroidism, and were followed up for > or =18 months. Third-generation M22-TBII and Mc4-TSI assays were performed in the chronic-inactive GO patients in whom euthyroidism status was restored. Patients' GO activity/severity clinical activity scores (CAS), and modified NOSPECS scores were examined for a correlation with TRAb assays. RESULTS: Fifty patients (mean age, 41.3 years; 41 females) were analyzed. The mean duration of Graves' hyperthyroidism symptom was 63 months (range, 18 to 401 months) and that of GO was 46 months (range, 18 to 240 months). All patients had been treated previously with anti-thyroid drugs for a median period of 52.3 months, and two patients underwent either radioiodine therapy or total thyroidectomy. Mean CAS and NOSPECS scores were 0.5 +/- 0.9 (standard deviation) and 4.8 +/- 3.1, respectively. Mean M22-TBII and Mc4-TSI values were 7.5 +/- 10.2 IL/L and 325.9 +/- 210.1 specimen-to-reference control ratio. TSI was significantly correlated with NOSPECS score (R = 0.479, p < 0.001); however, TBII was not associated with NOSPECS score (p = 0.097). Neither TSI nor TBII correlated with CAS (p > 0.05), because GO inflammatory activity subsided in the chronic stages of GO. CONCLUSIONS: In chronic-inactive GO after euthyroid restoration, GO activity score did not associate with serum levels of TRAb or TBII. However, levels of the functional antibody Mc4-TSI did correlate with GO severity. Therefore, the TSI bioassay is a clinically relevant measure of disease severity even in chronic inactive GO.
Adult ; Autoantibodies/*blood/immunology ; Chronic Disease ; Female ; Follow-Up Studies ; Graves Ophthalmopathy/*blood/diagnosis/immunology ; Humans ; Male ; Receptors, Thyrotropin/*blood/immunology ; Retrospective Studies ; Severity of Illness Index

The localization and functional characteristics of tumor necrosis factor(TNF) beta gene raise the possibility that it may be involved in the susceptibility to autoimmune thyroid diseases. To investigate whether a TNF beta gene polymorphism is associated with autoimmune thyroiditis, we analyzed the TNF beta gene polymorphism with the restriction enzyme NcoI in 48 Korean patients with atrophic autoimmune thyroiditis [23 were found to be thyrotropin binding inhibitor immunoglobulin(TBII) positive, 25 TBII negative], 52 goitrous autoimmune thyroiditis, and 129 healthy controls. Two TNF beta alleles were identified from the restriction fragment length polymorphism studies of amplified genomic DNA. In atrophic autoimmune thyroiditis patients positive for TBII, 7 of 23 patients were homozygous for the TNF beta * 1 allele, 3 were homozygous for the TNF beta * 2 allele, and 13 were TNF beta * 1/2 heterozygous compared to controls(P = 0.20). Also, there were no associations between the TNF beta gene polymorphism and either TBII-negative atrophic autoimmune thyroiditis or goitrous autoimmune thyroiditis. Of the HLA-class II antigens, the frequency of HLA-DR8 was significantly greater among the 23 Korean patients with TBII-positive atrophic autoimmune thyroiditis compared to control subjects (Pc = 0.003). When the HLA-DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis and controls were analyzed separately, the DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis had more homozygotes for the TNF beta * 1 allele(6/12, 50.0%) and no homozygotes for the TNF beta * 2 allele, as compared to the DR8 negative patients with TBII-positive atrophic autoimmune thyroiditis and DR8 positive controls(P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Alleles ; *Genetic Linkage ; HLA-DR Antigens/*genetics ; Humans ; Korea ; Lymphotoxin-alpha/*genetics ; *Polymorphism, Genetic ; Receptors, Thyrotropin/*immunology ; Thyroiditis, Autoimmune/*genetics

PURPOSE: To report clinical characteristics of thyroid-associated ophthalmopathy (TAO) in patients who previously underwent total thyroidectomy for thyroid cancer or a benign mass of the thyroid. MATERIALS AND METHODS: Of the patients who were diagnosed with TAO from March 2008 to March 2012, we performed a retrospective chart review on those who had undergone total thyroidectomy for thyroid cancer or a benign mass of the thyroid before the occurrence of ophthalmopathy. RESULTS: Of the 206 patients diagnosed with TAO, seven (3.4%) met the inclusion criteria. The mean age of the subjects was 47.4 years, and all were female. Six patients were diagnosed with papillary thyroid cancer, and one was diagnosed with a benign mass. The duration between total thyroidectomy and onset of TAO ranged from 3-120 months (median 48 months). Ophthalmic manifestations varied among cases. Except for the patient who was diagnosed with a benign mass, all patients showed hyperthyroid status and were under Synthroid hormone treatment at the time of TAO development. Five of these six patients had positive levels of thyroid-stimulating hormone (TSH) receptor autoantibodies. CONCLUSION: TAO rarely develops after total thyroidectomy, and the mechanism of TAO occurrence is unclear. However, most patients showed abnormalities in thyroid function and TSH receptor autoantibodies.
Adult ; Aged ; Autoantibodies/blood ; Carcinoma ; Carcinoma, Papillary/immunology/surgery ; Female ; Graves Ophthalmopathy/*diagnosis/immunology ; Humans ; Male ; Middle Aged ; Postoperative Complications/etiology/immunology/pathology ; Receptors, Thyrotropin ; Retrospective Studies ; Thyroid Neoplasms/complications/*surgery ; Thyroidectomy/adverse effects/*methods ; Thyrotropin/blood ; Treatment Outcome

PURPOSE: To investigate an association between the levels of serum thyroid-stimulating hormone (TSH)-receptor autoantibodies (TRAbs) and Graves' orbitopathy (GO) activity/severity scores, and compare the performance of three different TRAb assays in assessing the clinical manifestations of GO. MATERIALS AND METHODS: Cross-sectional study. Medical records of 155 patients diagnosed with GO between January 2008 and December 2010 were reviewed. GO activity was assessed by clinical activity score (CAS) and severity graded with the modified NOSPECS score by a single observer. Serum TRAb was measured by three different methods: 1st generation thyrotropin-binding inhibitor immunoglobulin (TBII) assay (TRAb1st); 3rd generation TBII assay (TRAb3rd); and biological quantitative assay of thyroid-stimulating immunoglobulin (TSI) using Mc4-CHO cells (Mc4-CHO TSI assay). Results were correlated with scores of activity/severity of thyroid eye disease. RESULTS: All three assays (TRAb1st, TRAb3rd, and Mc4-CHO TSI) yielded results that were significantly positively correlated with CAS (beta=0.21, 0.21, and 0.46, respectively; p<0.05) and proptosis (beta=0.38, 0.34, and 0.33, respectively; p<0.05). Mc4-CHO TSI bioassay results were significantly positively correlated with all GO severity indices (soft tissue involvement, proptosis, extraocular muscle involvement, and total eye score; beta=0.31, 0.33, 0.25, and 0.39, respectively; p<0.05). CONCLUSION: Mc4-CHO TSI bioassay was superior over the two TBIIs in assessing active inflammation and muscle restriction due to GO, whereas TBII assay would be sufficient for evaluation of patients with proptosis.
Adult ; Animals ; Autoantibodies/*blood ; CHO Cells ; Cricetulus ; Cross-Sectional Studies ; Female ; Graves Ophthalmopathy/blood/*etiology/*immunology ; Humans ; Immunoassay/*methods ; Male ; Middle Aged ; Receptors, Thyrotropin/blood/*immunology

OBJECTIVETo explore the role of natural killer T (NK T) cells in the pathogenesis of Graves' disease.

METHODSNK T cell deficient mice and wild BALB/c mice were immunized with cells expressing TSH receptor once every two weeks 6 times. Two weeks after the final immunization, the mice were killed and serum thyroxine levels, anti-TSH receptor antibodies and thyroid pathological changes were examined.

RESULTSThe mean levels of TT(4) and TRAb in the immunized NK T cell deficient group were slightly elevated but significantly different from those of the non-immunized control group, while comparable to those in the immunized wild group. There were no significant changes of the activity levels of TSAb or TSBAb in the immunized NK T cell deficient mice compared to those in immunized wild control mice. Thyroids from immunized NK T cell deficient mice showed mild hypertrophy of some follicles as compared with non-immunized control mice. This change was comparable to immunized wild control mice.

CONCLUSIONNK T cells may not be involved in the pathogenesis of Graves' disease.

Animals ; CHO Cells ; Cricetinae ; Female ; Graves Disease ; etiology ; immunology ; Immunization ; Killer Cells, Natural ; physiology ; Mice ; Mice, Inbred BALB C ; Receptors, Thyrotropin ; immunology ; Thyroid Gland ; pathology

OBJECTIVETo assess the association of tumour necrosis factor-α (TNF-α) gene polymorphisms at positions -863C/A, -857C/T, -238G/A and Graves disease (GD) susceptibility in Chinese Han population in Anhui region.

METHODSThe polymorphisms of TNF-α gene were determined by polymerase chain reaction with specific primers in 254 patients affected with GD and 212 healthy controls. Allelic and genotypic frequencies in GD group and normal controls as well as in different genders were compared. The allelic and genotypic frequencies for different thyroid stimulating hormone receptor antibody (TRAb) levels (TRAb > 12 U/L; ≤12 U/L) were also compared among patients with earlier onset GD.

RESULTS(1) The A allele at -863C/A locus in GD group (16.73%) was significantly greater than that of the control group (11.79%) (P< 0.05, OR = 1.503); the frequency of AA+CA genotype of -863C/A locus in GD group (32.68%) was significantly greater than that of control group (23.58%) (P< 0.05, OR = 1.573). There was no significant difference (P> 0.05) in the allelic and genotypic frequencies of -857C/T, -238G/A loci between the two groups. (2) There was no significant difference (P> 0.05) in the allelic and genotypic frequencies of -863C/A, -857C/T, -238G/A loci between patients of different genders. (3) There was no significant difference (P>0.05) in such frequencies between patients with earlier onset GD and different TRAb levels (TRAb > 12 U/L; ≤12 U/L).

CONCLUSION(1) The -863 A allele of TNF-α gene may contribute to the development of GD in Chinese Han population in Anhui, whilst -857C/T, -238G/A alleles may not. (2) There is no association between TNF-α gene -863C/A, -857C/T, -238G/A polymorphisms and development of GD in different genders. (3) There was no association between above polymorphisms and TRAb levels in patients with earlier onset GD.

Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; genetics ; Female ; Genetic Predisposition to Disease ; Graves Disease ; genetics ; immunology ; Humans ; Immunoglobulins, Thyroid-Stimulating ; genetics ; immunology ; Male ; Middle Aged ; Polymorphism, Genetic ; Receptors, Thyrotropin ; genetics ; immunology ; Tumor Necrosis Factor-alpha ; genetics ; immunology ; Young Adult

Thymic hyperplasia is frequently observed in Graves' disease. However, detectable massive enlargement of the thymus is rare, and the mechanism of its formation has remained elusive. This case showed dynamic changes in thymic hyperplasia on serial computed tomography images consistent with changes in serum thyrotropin receptor (TSH-R) antibodies and thyroid hormone levels. Furthermore, the patient's thymic tissues underwent immunohistochemical staining for TSH-R, which demonstrated the presence of thymic TSH-R. The correlation between serum TSH-R antibody levels and thymic hyperplasia sizes and the presence of TSH-R in her thymus suggest that TSH-R antibodies could have a pathogenic role in thymic hyperplasia.
Adult ; Female ; Graves Disease/*complications/surgery/therapy ; Humans ; Male ; Receptors, Thyrotropin/blood ; Thymus Gland/diagnostic imaging ; Thymus Hyperplasia/*diagnostic imaging/etiology/immunology ; Thyroid Hormones ; Thyroidectomy ; Thyrotropin/blood ; Tomography, X-Ray Computed ; Young Adult