Increased serum concentration of eosinophil-derived neurotoxin in patients with Graves' disease.

Eosinophil-derived neurotoxin (EDN) is released after activation and stimulation of eosinophils in allergic disease, which is a T(H)2-predominant condition. We previously reported that Graves' thyrotoxicosis develops or relapses after an attack of allergic rhinitis. In this study, to confirm the relation between Graves' disease and the allergic condition, we determined the serum level of EDN in 30 untreated patients with Graves' disease, 50 patients with Hashimoto's thyroiditis, and 39 normal controls. Compared to the serum level in normal subjects (30.1 +/- 15.6 ng/mL), EDN was increased in untreated patients with Graves' disease (52.4 +/- 27.6 ng/mL), but not in patients with Hashimoto's thyroiditis (thyrotoxic, 30.9 +/- 13.4 ng/mL; euthyroid, 30.0 +/- 11.9 ng/mL; hypothyroid, 23.4 +/- 10.2 ng/mL). A significant correlation was observed between the EDN level and the serum activity of thyrotropin (TSH) receptor antibody (r = 0.541, p < 0.0001). These data suggest that the allergic condition is closely related to Graves' disease and that a T(H)2-type immune response is crucial in the pathogenesis of Graves' disease.     

Endothelin-1 levels in patients with disorders of the thyroid gland.

The endothelium derived peptide endothelin-1 (ET-1) is the major isoform of the endothelin peptide family, which is produced and secreted in the endothelial cell system. We measured plasma levels in patients with thyroid diseases and investigated associations between laboratory and clinical markers of thyroid metabolism and ET-1 plasma levels. ET-1 plasma levels were determined in patients with Graves' disease (n = 54), endemic goiter (n = 26), patients with Hashimoto's thyroiditis (n = 21) and compared to healthy controls (n = 60). ET-1 plasma levels were significantly elevated in patients with Hashimoto's thyroiditis (p < 0.0001) and in patients with Graves' disease (p = 0.003), when compared to healthy controls. In patients with endemic goiter, no significant differences were found compared to healthy controls (p = 0.298) and when compared to patients with Graves' disease (p = 0.16). We did not observe an association between ET-1 plasma levels and parameters of thyroid disease (e.g. thyroidea-stimulating hormone, thyroxine, volume of the thyroid). Furthermore, patients with and without endocrine thyroid disease showed no significantly different ET-1 plasma levels (p = 0.78). These data suggest that the autoimmunologically induced inflammatory response of the thyroid gland in Hashimoto's thyroiditis and Graves' disease is responsible for increased ET-1 plasma levels. Furthermore, our data do not support a role for ET-1 as a valid quantitative indicator for stage or progression in endemic goiter, Graves' disease or Hashimoto's thyroiditis.     

Detection of antipituitary antibodies in patients with autoimmune thyroid disease.

The aim of the present study was to investigate the prevalence of antipituitary antibodies (APA) in patients with autoimmune thyroid disease as determined by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). Results by Western blot analysis showed positivity for APA in serum of 22.4% of patients with Graves' disease (n=143, p<0.05) and 18.5% of patients with Hashimoto's thyroiditis (n=54, p<0.05), which were significantly higher than 6.2% in healthy controls (n=97). Similar results were obtained with ELISA. The titers of APA measured by ELISA (APA/ELISA) remained unchanged before and after therapy with antithyroid drug for Graves' disease, while thyrotropin-binding inhibitor immunoglobulins (TBII) decreased significantly. Similarly, no changes in APA by Western blot analysis were observed after therapy. In patients with Graves' disease, APA were not associated with thyroid status. There was no difference in APA between patients with positive and negative thyroid autoantibodies. A significant but weak positive correlation between APA/ELISA and anti-human GH measured by ELISA (anti-hGH/ELISA) was observed in patients with Graves' disease (r=0.601 p<0.001) and Hashimoto's thyroiditis (r=0.428 p<0.005). These findings have demonstrated the existence of APA detected by Western blot analysis and ELISA in some cases of autoimmune thyroid disease. The present results suggest that hGH and other antigens may be involved in APA in patients with Graves' disease and Hashimoto's thyroiditis.     

A promoter polymorphism of the CYP27B1 gene is associated with Addison's disease, Hashimoto's thyroiditis, Graves' disease and type 1 diabetes mellitus in Germans

BACKGROUND: CYP27B1 hydroxylase catalyzes the conversion of 25 hydroxyvitamin D(3) (25OHD(3)) to 1,25(OH)(2)D(3), the most active natural vitamin D metabolite, which plays a role in the regulation of immunity and cell proliferation. We therefore investigated two single nucleotide polymorphisms in the CYP27B1 hydroxylase gene for an association with Addison's disease, Hashimoto's thyroiditis, Graves' disease and type 1 diabetes mellitus. METHODS: Patients with Addison's disease (n=124), Hashimoto's thyroiditis (n=139), Graves' disease (n=334), type 1 diabetes mellitus (n=252) and healthy controls (n=320) were genotyped for the promoter (-1260) C/A polymorphism and for the intron 6 (+2838) C/T polymorphism of the CYP27B1 gene. Patients and controls were compared using genotype-wise and allele-wise X(2) testing. RESULTS: A significant association was found between allelic variation of the promoter (-1260) C/A polymorphism and Addison's disease, Hashimoto's thyroiditis, Graves' disease and type 1 diabetes mellitus (P=0.0062, P=0.0173, P=0.0094 and P=0.0028 respectively). Significant differences were also observed for the intron 6 (+2838) C/T polymorphism (P=0.0058) in Hashimoto's thyroiditis but not for the other autoimmune endocrine diseases. CONCLUSIONS: The CYP27B1 promoter (-1260) C/A polymorphism appears to be associated with endocrine autoimmune diseases but the CYP27B1 intron 6 (+2838) C/T polymorphism appears to be associated only with Hashimoto's thyroiditis. These results imply a regulatory difference of the CYP27B1 hydroxylase to predispose to endocrine autoimmunity.     

Activated (Ia+) T-lymphocytes and their subsets in autoimmune thyroid diseases: analysis by dual laser flow microfluorocytometry

Peripheral blood lymphocytes of patients with autoimmune thyroid diseases were studied using monoclonal antibodies reacting with cell surface antigens of activated T-cells (Ia+T), as well as their helper-inducer (Ia+TH/I) and suppressor-cytotoxic (Ia+TS/C) subsets, using two-color dye labeling and dual laser activated cell sorter analyses. Compared to normal subjects, hyperthyroid Graves' disease patients had significantly higher percent Ia+T values in association with an increase in percent Ia+TH/I as well as a reduction in percent Ia+TS/C; whereas patients with hypothyroid Hashimoto's thyroiditis as well as those with postpartum thyroiditis studied in the hyperthyroid phase also had a significant but lesser increase in percent Ia+T-cells, but their percent Ia+TH/I subset was significantly decreased, whereas the percent Ia+TS/C subset was increased; and patients with toxic nodular goiter or factitious hyperthyroidism (nonimmunogenic causes of hyperthyroidism) had a significant increase in percent Ia+T-cells without a significant difference in their Ia+T subsets or their ratios in comparison to controls. These studies demonstrated the feasibility of detecting Ia+T-cells and their subset characteristics using two-color dye labeling and dual laser flow microfluorocytometric methodology. In both the active and treated phases of Graves' disease, Hashimoto's thyroiditis, and postpartum thyroiditis, the percent Ia+T-cells was increased compared to normal subjects, with the highest values occurring in hyperthyroid Graves' disease. Furthermore, patients with hyperthyroid Graves' disease had the opposite changes in percent Ia+TH/I and Ia+TS/C subsets as compared to patients with either untreated hypothyroid Hashimoto's disease or the hyperthyroid phase of postpartum thyroiditis, suggesting that the pathogenic mechanisms involved in Hashimoto's disease and the destructive hyperthyroidism of painless thyroiditis are similar, and that they are both distinctly different from that of hyperthyroid Graves' disease.     

Autoantibody tests in autoimmune thyroid disease: a case-control study.

Both positive antinuclear antibody (ANA) and anti-DNA antibodies have been reported in patients with autoimmune thyroid disease. We sought to determine the frequency of ANA and other autoantibodies in autoimmune thyroid disease versus control subjects. We measured ANA by 2 methods (mouse liver, HEp-2), anti-dsDNA, anti-Ro, anti-La, anti-Sm, anti-RNP, and anticardiolipin in 26 patients with Hashimoto's thyroiditis, 26 patients with Graves' disease, and 26 control patients. Positive ANA by either method were more common in patients with Graves' disease than in controls (p = 0.002 and 0.05). Although common (46.2%), ANA by HEp-2 method was not found significantly more often in patients with Hashimoto's thyroiditis than in controls. Evidence for systemic autoimmune diseases was not found: patients with autoimmune thyroid did not have autoantibodies other than ANA and did not differ from controls in rheumatologic symptoms. Positive ANA using the widely accepted HEp-2 method were commonly found in both Graves' disease and Hashimoto's thyroiditis. No evidence of subclinical systemic autoimmune disease was found, either by specific autoantibody tests or by increased frequency of rheumatologic symptoms or signs.     

Propylthiouracil and carbimazole associated-antineutrophil cytoplasmic antibodies (ANCA) in patients with Graves' disease

OBJECTIVE: Propylthiouracil treatment of Graves' disease has been postulated to provoke antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. We aimed to investigate whether carbimazole therapy was also associated with increased risk of ANCA. DESIGN: The occurrence of ANCA and the relationship to thionamide treatment was investigated in a cross-sectional study in a consecutive series of 407 patients' with Graves' disease, 200 with Hashimoto's thyroiditis and 649 normal euthyroid subjects. MEASUREMENTS: ANCA was measured by indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) for proteinase 3 and myeloperoxidase-ANCA. RESULTS: The prevalence of ANCA, as measured by IIF, was increased in the Graves' disease cohort (19.9%) compared with euthyroid controls (4.6%; P < 0.001). The prevalence of MPO-ANCA (measured by ELISA) was also increased in Graves' disease (P = 0.019). ANCA prevalence was more strongly associated with propylthiouracil treatment than carbimazole (P = 0.0265), although risk of ANCA was also higher in Graves' patients treated with carbimazole than controls (RR 2.2, P < 0.0001). ANCA positivity was not increased in patients with Hashimoto's thyroiditis. CONCLUSION: This study revealed a high prevalence of ANCA in treated patients with Graves' disease but not in those with Hashimoto's thyroiditis. Furthermore, within the Graves' disease population, ANCA development was associated with propylthiouracil usage to a greater extent than carbimazole. These findings suggest that the altered immune environment associated with autoimmune thyroid disease is not sufficient to develop ANCA but treatment with thionamides is important in promoting ANCA development.     

Studies on suppressor cell function in thyroid diseases.

Suppressor cell function of peripheral mononuclear cells has been examined in patients with Graves' disease, Hashimoto's thyroiditis, and thyroid cancer, as well as in healthy subjects. Suppressor cell function was assessed through two methods: 1) measurement of enhanced blastogenesis after 24-h preculture and 2) concanavalin A-inducible suppressor activity. The results from the two tests were coincident and indicate that suppressor cell function was significantly decreased in the Graves' disease population but not changed in either the Hashimoto's thyroiditis or the thyroid cancer groups compared to healthy controls. The impairment of suppressor cell function in the Graves' disease population was still observed when patients became euthyroid by treatment with antithyroid drugs, although the treated patients had improved suppressor cell function compared to untreated patients (P = NS). Low activity of suppressor cell function in the Graves' disease population might be a constitutional character based on an inherited abnormality specific for the disease population.     

Thyroid fetal male microchimerisms in mothers with thyroid disorders: presence of Y-chromosomal immunofluorescence in thyroid-infiltrating lymphocytes is more prevalent in Hashimoto's thyroiditis and Graves' disease than in follicular adenomas

The presence of fetal cells in a maternal compartment is defined as fetal-maternal microchimerism, which has been detected in thyroids of mothers suffering from autoimmunity. We analyzed the immunohistology of paraffin-embedded thyroid specimen taken at surgery from 49 women with Hashimoto's thyroiditis (n = 25), Graves' disease (n = 15), or nodular or diffuse follicular adenomas (n = 9), whose childbirth history was positive for sons. By fluorescence in situ hybridization we screened for X-chromosome- and Y-chromosome-specific staining and compared the finding with human leukocyte antigen (HLA) DQ types of the mothers and, where available, their offspring. In 23 thyroids we found Y-chromosome-specific staining, which was more frequent in thyroid autoimmune disease (60% Hashimoto's thyroiditis and 40% Graves' disease) than in follicular adenomas (22.2%). There was no significant difference for HLA DQ alleles among women whose thyroids showed Y-chromosome staining and those without. However, a subgroup of all investigated microchimerism-positive mother-child pairs and women with Hashimoto's thyroiditis and Graves' disease more often had the susceptibility alleles HLA DQA1*0501-DQB1*0201 or DQB1*0301. In conclusion, fetal microchimerism is observed in thyroids of mothers with sons, and this is found more frequently in thyroid autoimmune diseases.     

Association of HLA antigen and restriction fragment length polymorphism of T cell receptor beta-chain gene with Graves' disease and Hashimoto's thyroiditis

HLA antigen phenotypes and BglII restriction fragment length polymorphism of T cell receptor beta-chain (TCR beta) gene were analyzed in 61 patients with Graves' disease and 50 patients with Hashimoto's thyroiditis. The antigen frequency of HLA-Bw46 in both Graves' disease (23.0%) and Hashimoto's thyroiditis (24.0%) was significantly higher than that in normal population (8.0%), with relative risks (RR) of 3.45 [corrected P (Pc) less than 0.009] and 3.66 (Pc less than 0.02), respectively. Significantly increased frequency of HLA-B51 antigen was also found in Hashimoto's thyroiditis (40.0% vs. 16.3% in controls; RR, 3.42; Pc less than 0.002). Hybridization of BglII-digested DNA with TCR beta probe revealed two alleles of 9.3 and 8.6 kilobases. The allele frequency of 8.6 kilobases in Graves' disease (79%) and Hashimoto's thyroiditis (76%) was significantly higher (P less than 0.01 and P less than 0.05, respectively) than that in controls (64%). The frequency of homozygous state 8.6/8.6 was significantly increased in both Graves' disease (62%) and Hashimoto's thyroiditis (60%) over that in controls (39%); the RR of 8.6/8.6 in Graves' disease and Hashimoto's thyroiditis were 2.55 (P less than 0.01) and 2.31 (P less than 0.05), respectively. These results indicate that in Japanese subjects at least two loci are involved in the susceptibility to Graves' disease and Hashimoto's thyroiditis, one related to HLA and another to TCR beta.     

Quantitative measurement of thyroid blood flow for differentiation of painless thyroiditis from Graves' disease

OBJECTIVE: Differentiation between destruction-induced thyrotoxicosis and Graves' thyrotoxicosis is important for selection of proper therapy. It is, however, often difficult to make this distinction without measurement of radioactive iodine uptake. We investigated the possibility that assessment of thyroid blood flow would allow differentiation between the two entities. PATIENTS AND MEASUREMENTS: One hundred and fourteen untreated patients with thyrotoxicosis (56 Graves' disease, 28 painless thyroiditis, 30 subacute thyroiditis) and 25 normal controls were examined. Serum levels of freeT4 (FT4), freeT3 (FT3) and TSH were measured by chemiluminescent immunoassay, and anti-TSH receptor antibodies (TSH-binding inhibitory immunoglobulin, TBII) were measured by enzyme-linked immunosorbent assay. Thyroid volume and blood flow (TBF) were measured quantitatively by ultrasonography. RESULTS: TBF was significantly higher in Graves' disease (mean +/- 1SD: 14.9 +/- 6.4%, P < 0.0001) than in painless thyroiditis (0.8 +/- 0.5%), subacute thyroiditis (0.9 +/- 0.7%) and in normal controls (0.8 +/- 0.5%). All patients with Graves' disease had TBF values of more than 4% and all patients with painless thyroiditis and subacute thyroiditis had TBF values less than 4%. TBF values significantly correlated with values of radioactive iodine uptake (RAIU) either at 3 h (r = 0.492, P < 0.01) or 24 h (r = 0.762, P < 0.001) within the Graves' disease and painless thyroiditis groups. There was no relationship between TBF values and thyroid volumes or values of TBII in the Graves' disease group. All patients with Graves' disease had positive TBII of 15% or more. Three of 28 patients with painless thyroiditis and one of 30 patients with subacute thyroiditis had positive TBII. CONCLUSION: TBF was quantitatively measured by power Doppler ultrasonography and was more effective than TBII for differentiation between destruction-induced thyrotoxicosis (painless or subacute thyroiditis) and Graves' thyrotoxicosis. TBF values of less than 4% in untreated thyrotoxic patients are laboratory signals of destruction-induced thyrotoxicosis and if these are determined, the radioactive iodine uptake test can be omitted for differential diagnosis of these two types of thyrotoxicosis.     

A C/T polymorphism in the 5'-untranslated region of the CD40 gene is associated with Graves' disease in Koreans.

The genetic loci conferring susceptibility to Graves' disease remain unclear. The aim of the present study was to examine a C/T polymorphism in the 5'-untranslated region of the CD40 gene and its relationship with autoimmune thyroid diseases in Koreans. The C/T polymorphism in the 5'-untranslated region of CD40 gene, clinical characteristics, and thyroid antibodies were analyzed in a series of Korean patients (132 with Graves' disease, 118 with Hashimoto's thyroiditis, and 164 normal controls). The CC genotype was significantly associated with Graves' disease (odds ratio, 1.93; 95% confidence interval, 1.21-3.09; corrected p = 0.019). On the other hand, the frequency of the TT genotype was significantly lower in Graves' patients than in controls (8% vs. 18%; odds ratio, 0.38; 95% confidence interval, 0.18-0.82; corrected p = 0.044). Allele frequencies in CD40 did not differ from controls in patients with Hashimoto's thyroiditis. In patients with Graves' disease, there were significant differences between genotypic groups in the activity of stimulating thyrotropin (TSH) receptor antibody. However, clinical characteristics and other thyroid antibodies were not significantly different. In conclusion, the C allele in the 5'-untranslated region of the CD40 gene may confer genetic susceptibility to Graves' disease in Koreans.     

Multicenter study on TGPO autoantibody prevalence in various thyroid and non-thyroid diseases; relationships with thyroglobulin and thyroperoxidase autoantibody parameters

OBJECTIVE: TGPO autoantibodies (aAbs) that bind simultaneously to thyroglobulin (Tg) and thyroperoxidase (TPO) are present in the serum of patients with autoimmune thyroid diseases (AITD) and have been found to differ from monospecific Tg and TPO aAbs. To obtain further insights on the prevalence defined as the rate of occurrence and significance of TGPO aAbs in a large population, we carried out a collaborative study involving 15 European teams. METHODS: Serum samples from 3122 patients with various thyroid and non-thyroid diseases and normal subjects were assayed using a novel TGPO aAb detection kit. This test was designed so that TGPO aAbs are trapped between the Tg-coated solid phase and the soluble TPO labeled with a radioiodinated monoclonal antibody. RESULTS: Only three out of the 220 normal subjects (prevalence of 1.4%) were found to have positive TGPO aAb levels, which were mainly observed in the patients with AITD: the group of patients suffering from Hashimoto's thyroiditis had a TGPO aAb prevalence of 40.5% (n=437 patients), those with Graves' disease, a prevalence of 34.6% (n=645) and those with post-partum thyroiditis, 16.0% (n=243). Among the non-AITD patients with positive TGPO aAb levels, the TGPO aAb prevalence ranged from 20.7% among those with thyroid cancer (n=246) to 0% among those with toxic thyroid nodules (n=47). Among the patients with non-thyroid diseases, the TGPO aAb prevalence ranged from 9.8% in the case of Biermer's pernicious anemia (n=78) to 0% in that of premature ovarian failure (n=44). It is worth noting that the groups showing the highest TGPO aAb prevalence also contained the patients with the highest TGPO aAb titers. Statistical comparisons between the TGPO aAb prevalences in the various groups showed that TGPO aAb could be used as a parameter to distinguish between the groups of Hashimoto's and Graves' patients and between the women with post-partum thyroiditis and the post-partum women with only Tg and/or TPO aAb established during early pregnancy. Unexpectedly, the correlations between TGPO aAbs and Tg and TPO aAbs were found to depend mainly on the assay kit used. CONCLUSION: High TGPO aAb titers are consistently associated with AITD but the reverse was not found to be true. TGPO aAbs are a potentially useful tool, however, for establishing Hashimoto's diagnosis, and would be worth testing in this respect with a view to using them for routine AITD investigations.     

Thyroid vascularity and blood flow are not dependent on serum thyroid hormone levels: studies in vivo by color flow doppler sonography

OBJECTIVE: Thyroid blood flow is greatly enhanced in untreated Graves' disease, but it is not known whether it is due to thyroid hormone excess or to thyroid hyperstimulation by TSH-receptor antibody. To address this issue in vivo patients with different thyroid disorders were submitted to color flow doppler sonography (CFDS). SUBJECTS AND METHODS: We investigated 24 normal subjects, and 78 patients with untreated hyperthyroidism (49 with Graves' hyperthyroidism, 24 with toxic adenoma, and 5 patients with TSH-secreting pituitary adenoma (TSHoma)), 19 patients with thyrotoxicosis (7 with thyrotoxicosis factitia, and 12 with subacute thyroiditis), 37 euthyroid patients with goitrous Hashimoto's thyroiditis, and 21 untreated hypothyroid patients with Hashimoto's thyroiditis. RESULTS: Normal subjects had CFDS pattern 0 (absent or minimal intraparenchimal spots) and mean intraparenchimal peak systolic velocity (PSV) of 4.8+/-1.2cm/s. Patients with spontaneous hyperthyroidism due to Graves' disease, TSHoma, and toxic adenoma had significantly increased PSV (P<0.0001, P=0.0004, P<0.0001 respectively vs controls) and CFDS pattern. Patients with Graves' disease had CFDS pattern II (mild increase of color flow doppler signal) in 10 (20%) and pattern III (marked increase) in 39 cases (80%). Mean PSV was 15+/-3cm/s. Patients with toxic adenoma had CFDS pattern I (presence of parenchymal blood flow with patchy uneven distribution) in 2 (8%), pattern II in 16 (70%) and pattern III in 5 (22%). Mean PSV was 11+/-2.4cm/s. Patients with TSHoma showed CFDS pattern I in one case (20%) and pattern II in 4 (80%). Mean PSV was 14.8+/-4.2cm/s. Patients with thyrotoxicosis had normal PSV (4.2+/-1. 1cm/s in subacute thyroiditis, 4+/-0.8cm/s in thyrotoxicosis factitia, P=not significant vs controls) and CFDS pattern 0. Untreated euthyroid patients with goitrous Hashimoto's thyroiditis had CFDS pattern 0, and mean PSV (4.3+/-0.9cm/s; P=not significant vs controls). Untreated hypothyroid patients with goitrous Hashimoto's thyroiditis had CFDS pattern I in 14 cases (67%), pattern II in 4 (19%) and pattern 0 in 3 (14%) and mean PSV (5.6+/-1. 4cm/s) was higher than that of controls (P=0.026). CONCLUSIONS: An increase in both intrathyroidal vascularity and blood velocity was observed in patients with spontaneous hyperthyroidism but not in thyrotoxicosis due to either ingestion of thyroid hormones or to a thyroidal destructive process. The slightly increased vascularity and blood velocity observed in patients with hypothyroid Hashimoto's thyroiditis suggests that thyroid stimulation by either TSH-receptor antibody or TSH is responsible for the increased thyroid blood flow.     

Changes in thyroid-stimulating immunoglobulins during antithyroid therapy

Thyroid-stimulating immunoglobulin (TSI) activity was measured by radioreceptor assay in sera from patients with Graves' disease, Hashimoto's thyroiditis, and thyroid cancer. In untreated Graves' disease (47 cases), TSI index was significantly lower [76.7 +/- 1.4 (SE)] than the average of a normal control group (30 cases; 94.4 +/- 1.9). In untreated Hashimoto's thyroiditis (25 cases), it was also significantly lower (83.0 +/- 2.4). In patients with thyroid cancer (19 cases), there was no significant difference from normal controls. After 131I treatment, the TSI index in Graves' disease decreased during 2--4 months, then increased and reached normal levels in 1 yr. During propylthiouracil treatment, the TSI index increased and reached a normal level in 5--6 months without the decreasing phase seen after 131I treatment. Free T4 index values were gradually decreased by both treatments. There was no significant relationship between TSI index and thyroid antibodies (microsomal antibodies and thyroglobulin antibodies) in untreated Graves' disease or Hashimoto's thyroiditis. It is concluded that 1) in the sera of patients with Graves' disease and Hashimoto's thyroiditis, there are immunoglobulin Gs that can displace TSH binding to thyroid membranes; 2) these immunoglobulins Gs are different from the classic antithyroid antibodies; and 3) 131T treatment of Graves' disease may enhance TSI production during the first 1--2 months after therapy.     

Circulating monocyte (macrophage)-specific antibodies in patients with autoimmune thyroid diseases

We investigated the presence of circulating monocyte-specific antibodies (monocytotoxic activities) by cytotoxicity tests and also the relationships between these monocytotoxic activities and the clinical data in autoimmune thyroid diseases. Subjects of this investigation include 16 patients with Graves' disease, 20 patients with Hashimoto's thyroiditis and 10 normal controls. To obtain monocyte-rich population, peripheral blood mononuclear cells of type 0 healthy donor were incubated on culture dishes for 12 hours and dish adherent cells were separated by pipetting. These monocyte-rich population were incubated with sample sera which were previously absorbed by lymphocytes of many different kinds of HLA types to eliminate anti-lymphocyte antibodies, and thereafter cytotoxicity tests were performed by adding rabbit complements. The monocytotoxic activities were expressed by %cytotoxicities and the value of %cytotoxicity over 3.9% (mean + 4SD of %cytotoxicities of normal controls) was considered to be positive in monocytotoxic activity. The results indicate that; 1) 8 patients (50%) of Graves' disease and 10 patients (50%) of Hashimoto's thyroiditis had positive values of monocytotoxic activity. 2) These positive values of monocytotoxic activity were markedly decreased after absorption of sample sera by monocytes, and these patients who had positive values of monocytotoxic activities to allogenic monocytes also had positive values of monocytotoxic activities to autologous monocytes. 3) Patients who had positive monocytotoxic activities also had high levels of TSH receptor antibody (TRAb) and anti-microsomal antibody, besides, monocytotoxic activity was significantly correlated with levels of TRAb in Graves' disease.(ABSTRACT TRUNCATED AT 250 WORDS)     

Vitamin D 1alpha-hydroxylase (CYP1alpha) polymorphism in Graves' disease,Hashimoto's thyroiditis and type 1 diabetes mellitus

OBJECTIVE: The vitamin D endocrine system plays a role in the regulation of (auto)immunity and cell proliferation. Vitamin D 1alpha-hydroxylase (CYP1alpha) is one of the key enzymes regulating both systemic and tissue levels of 1,25-dihyroxyvitamin D(3) (1,25(OH)(2)D(3)). Administration of 1,25(OH)(2)D(3), whose serum levels were found to be reduced in type 1 diabetes and thyroid autoimmunity, prevents these diseases in animal models. We therefore investigated a recently reported CYP1alpha polymorphism for an association with type 1 diabetes mellitus, Graves' disease and Hashimoto's thyroiditis. DESIGN AND METHODS: Four hundred and seven Caucasian pedigrees with one offspring affected by either type 1 diabetes (209 families), Graves' disease (92 families) or Hashimoto's thyroiditis (106 families) were genotyped for a C/T polymorphism in intron 6 of the CYP1alpha gene on chromosome 12q13.1-13.3 and transmission disequilibrium testing (TDT) was performed. Subsets of affected offspring stratified for HLA-DQ haplotype were compared using chi(2) testing. RESULTS: There was no deviation from the expected transmission frequency in either type 1 diabetes mellitus (P=0.825), Graves' disease (P=0.909) or Hashimoto's thyroiditis (P=0.204). However, in Hashimoto's thyroiditis the CYP1alpha C allele was significantly more often transmitted to HLA-DQ2(-) patients (27 transmitted vs 14 not transmitted; TDT: P=0.042) than expected. The C allele was less often transmitted to HLA-DQ2(+) patients (9 transmitted vs 12 not transmitted; TDT: P=0.513), although the difference was not significant (chi(2) test: P=0.143). A similar difference was observed in type 1 diabetes between offspring with high and low risk HLA-DQ haplotypes (chi(2) test: P=0.095). CONCLUSIONS: The CYP1alpha intron 6 polymorphism appears not to be associated with type 1 diabetes mellitus, Graves' disease and Hashimoto's thyroiditis. A potential association in subsets of patients with type 1 diabetes and Hashimoto's thyroiditis should be further investigated as well as its functional implications.     

Ratio of serum free triiodothyronine to free thyroxine in Graves' hyperthyroidism and thyrotoxicosis caused by painless thyroiditis

The serum T3 to T4 ratio is a useful indicator for differentiating destruction-induced thyrotoxicosis from Graves' thyrotoxicosis. However, the usefulness of the serum free T3 (FT3) to free T4 (FT4) ratio is controversial. We therefore systematically evaluated the usefulness of this ratio, based on measurements made using two widely available commercial kits in two hospitals. Eighty-two untreated patients with thyrotoxicosis (48 patients with Graves' disease and 34 patients with painless thyroiditis) were examined in Kuma Hospital, and 218 patients (126 with Graves' disease and 92 with painless thyroiditis) and 66 normal controls were examined in Ito Hospital. The FT3 and FT4 values, as well as the FT3/FT4 ratios, were significantly higher in the patients with Graves' disease than in those with painless thyroiditis in both hospitals, but considerable overlap between the two disorders was observed. Receiver operating characteristic (ROC) curves for the FT3 and FT4 values and the FT3/FT4 ratios of patients with Graves' disease and those with painless thyroiditis seen in both hospitals were prepared, and the area under the curves (AUC), the cut-off points for discriminating Graves' disease from painless thyroiditis, the sensitivity, and the specificity were calculated. AUC and sensitivity of the FT(3)/FT(4) ratio were smaller than those of FT(3) and FT(4) in both hospitals. The patients treated at Ito hospital were then divided into 4 groups according to their FT4 levels (A: < or =2.3, B: >2.3 approximately < or =3.9, C: 3.9 approximately < or =5.4, D: >5.4 ng/dl), and the AUC, cut-off points, sensitivity, and specificity of the FT(3)/FT(4) ratios were calculated. The AUC and sensitivity of each group increased with the FT4 levels (AUC: 57.8%, 72.1%, 91.1%, and 93.4%, respectively; sensitivity: 62.6%, 50.0%, 77.8%, and 97.0%, respectively). The means +/- SE of the FT3/FT4 ratio in the Graves' disease groups were 3.1 +/- 0.22, 3.1 +/- 0.09, 3.2 +/- 0.06, and 3.1 +/- 0.07, respectively, versus 2.9 +/- 0.1, 2.6 +/- 0.07, 2.5 +/- 0.12, and 2.3 +/- 0.15, respectively, in the painless thyroiditis groups. In the painless thyroiditis patients, the difference in the FT3/FT4 ratio between group A and group D was significant (p<0.05). Thus, the FT3/FT4 ratio in patients with Graves' disease likely remains unchanged as the FT4 level rises, whereas this ratio decreases as the FT4 level rises in patients with painless thyroiditis. In conclusion, the FT3/FT4 ratios of patients with painless thyroiditis overlapped with those of patients with Graves' disease. However, this ratio was useful for differentiating between these two disorders when the FT4 values were high.     

T lymphocyte subsets in autoimmune thyroid diseases and subacute thyroiditis detected with monoclonal antibodies

Peripheral T lymphocyte subsets were analysed with monoclonal antibodies, by highly standardized fluorescence-activated cell sorter analysis instead of manual counting by the indirect immunofluorescence method, in autoimmune thyroid diseases and subacute thyroiditis. Total lymphocyte counts were increased in patients with thyrotoxic Graves' disease and subacute thyroiditis. The percentage of total T (Leu 1) cells was significantly lower in patients with thyrotoxic Graves' disease and Hashimoto's disease with destructive thyrotoxicosis than in normal subjects. No significant changes were observed in the percentages of suppressor-cytotoxic T (Leu 2a) cells or helper-inducer T (Leu 3a) cells or in the Leu 3a-Leu 2a ratio in different groups of patients. There were no correlations between the percentages of E rosette-forming cells and Leu 1 cells and between the percentages of T gamma cells and Leu 2a cells in normal subjects and patients. The peak position of fluorescence intensity of Leu 2a cells showed a significant sex difference even in normal controls. The most important finding was a significant decrease in the peak position of Leu 2a cells in patients with thyrotoxic Graves' disease and with hypothyroid or thyrotoxic Hashimoto's disease. These findings indicate the significant association of qualitative, but not quantitative, abnormality of suppressor-cytotoxic T (Leu 2a) cells with thyroid dysfunction in autoimmune thyroid diseases.     

Increased serum concentration of interleukin-12 in patients with silent thyroiditis and Graves' disease.

We previously reported that interleukin-5 (IL-5), secreted from Th2 cells, was increased in patients with Graves' disease, but not in patients with silent thyroiditis. In this study, we investigated serum levels of interleukin-12 (IL-12) in order to examine the role of Th1-type immune response in the pathogenesis of autoimmune thyroid diseases. Serum levels of IL-12 were determined by a highly sensitive sandwich enzyme-linked immunosorbent assay in 68 patients with Hashimoto's thyroiditis (26 of whom had silent thyroiditis), 74 patients with Graves' disease, 8 patients with subacute thyroiditis, and 27 normal controls. Serum levels of IL-12 in thyrotoxic patients with silent thyroiditis (385.2 +/- 164.5 pg/mL, mean +/- SD), and in thyrotoxic patients with Graves' disease (343.6 +/- 163.8 pg/mL) were significantly increased compared with serum levels in normal subjects (163.9 +/- 66.8 pg/mL, p < 0.0001, p < 0.0001, respectively) or in thyrotoxic patients with subacute thyroiditis (241.9 +/- 46.5 pg/mL, p < 0.01, < 0.05, respectively). The ratio of IL-12 to IL-5 in thyrotoxic patients with silent thyroiditis (64.2 +/- 39.7) was significantly higher than that in normal controls (33.7 +/- 13.3, p < 0.01) or in thyrotoxic patients with Graves' disease (40.6 +/- 36.0, p < 0.05). These data suggest that Th1-type immune response is predominant in silent thyroiditis, and that not only Th2-type immune response but also Th1-type immune response is important in the pathogenesis of Graves' disease.