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OBJECTIVE Glycosaminoglycan (GAG) production by retro-ocular fibroblasts (REF) is increased in patients with thyroid-associated ophthalmopathy (TAO). Various cytokines stimulate REFs to proliferate and elaborate GAG, free oxygen radicals as well as induce HLA-DR expression on these cells. Pentoxifyllin (Ptx) regulates the production of several cytokines including tumor necrosis factor alpha (TNF-alpha), interleukin-1 (IL-1) and, interferon gamma (IFN-gamma). We wished in this study to determine whether Ptx modified the spontaneous and cytokine-induced GAG synthesis by REF and IFN-gamma induced HLA-DR expression. DESIGN REF derived from extraocular muscles of healthy subjects were cultured without and with cytokines (IFN-gamma, TNF alpha and IL-1) and the effect of Ptx on the production of GAG by REF and HLA-DR expression was determined. MEASUREMENTS Glycosaminoglycan was measured by incorporation of (3H) glycosamine into GAG. HLA-DR expression was analyzed by fluorescence activated cell sorter. RESULTS Both spontaneous and cytokine induced GAG synthesis by REF was inhibited by Ptx (100, 500 and 1000 mg/l, respectively). IFN-gamma (50, 100 and 500 U/ml) induced a dose-dependent increase in the expression of HLA-DR molecules by REF. Ptx, which was not toxic to REF, inhibited HLA-DR expression on those cells dose-dependently. CONCLUSIONS Our in vitro results suggest that Ptx reduces cytokine-induced GAG production and HLA-DR expression by REF. It thus has potential as a therapeutic agent which regulates the function of lymphocytes infiltrating the retro-orbital tissues, and which are instrumental in TAO.

A chemiluminescence method was developed to measure thyroid peroxidase (TPO) activity and the inhibitory effect of anti-TPO antibodies in purified porcine TPO. The TPO preparation was characterized kinetically and controlled by Western-blotting technique. The chemiluminescence method proved to be reproducible and much more sensitive than the widely used guaiacol method, being able to detect TPO concentrations of 2.21 × 10−5 g/L vs 6.63 × 10−2g/L with the latter. Otherwise, the determinations with the two methods correlated well (r = 0.76). Investigating the effect of IgGs from 23 hypothyroid patients on measured TPO activity, we detected inhibition in 19 cases with the chemiluminescence technique (15 with the guaiacol method). Anti-TPO antibodies showed competitive inhibition of TPO activity with respect to the substrate guaiacol. In both systems, the inhibition is present in the IgG F(ab′)2 fragment. We conclude that the high sensitivity of chemiluminescence detection allows routine determination of the inhibition of TPO activity by anti-TPO antibodies.

Recently, in vitro production of interleukin-2 receptor induced by mitogens have been shown to be impaired in autoimmune disorders including organo-specific autoimmune diseases. The aim of this study was to investigate serum levels of soluble interleukin-2 receptor in 20 untreated patients with Graves' disease and to follow up their changes in relation to clinical picture and TSH-receptor-, anti-thyroglobulin-, anti-microsomal as well as anti-eye muscle antibodies. Soluble interleukin-2 receptor level was significantly increased in newly-diagnosed Graves' patients compared to controls (667 +/- 270 vs. 205 +/- 45 U/ml) (P less than 0.001). Among the patients sera those with active infiltrative ophthalmopathy had higher soluble interleukin-2 receptor levels than those without eye symptoms (810 +/- 313 vs. 525 +/- 180 U/ml). Soluble interleukin-2 receptor level was normalized in Methimazole-treatment-induced remission in the majority of patients except those with ophthalopathy. In five patients the soluble interleukin-2 receptor levels were studied after interruption of thyrostatic therapy; an increase was observed in three patients; thereafter hyperthyrosis relapsed in two cases. Furthermore, a correlation was found between soluble interleukin-2 receptor levels and TSH-receptor antibodies, however, the association with other immune parameters examined was not significant. In conclusion, an enhanced level of soluble interleukin-2 receptor was detected in patients with untreated Graves' disease. This finding might play a significant role in regulation of impaired cell-mediated immune mechanism and has a prognostic value for relapse of autoreactive processes.

Thyroid nodules are common. It would very helpful if genetic markers that can diagnose malignancy from fine needle aspiration samples were available. Few such markers has been thus identified and none are specific. Large panels of potential markers can be screened by microarray technology. Studies done to date have concentrated on single tumor types and thus provide no help in identifying tumor subtype specific markers. To that end we have studied gene profiles of 5 types of benign and malignant thyroid nodular tissue (multinodular goiter, follicular adenoma, papillary and follicular carcinomas). We have identified 195 genes whose differential expression clustered into clinically relevant groups. Twenty-eight genes were selected for further confirmation using real time quantitative polymerase chain reaction. Despite the differences in the microarray panels used, we confirmed the differential regulation of 12 genes previously reported in thyroid cancer, although we found the expression of several genes to be regulated in other histological tumor subtypes than originally described. We found, PCSK2, TRIB1, RAP1 GA1 to be specifically overexpressed in follicular cancer and S100A4 and GK2 in papillary carcinoma. SERP1, RNASE 2 and STATA5 were suppressed in papillary thyroid cancer. We have thus identified new potential markers specific to malignant thyroid tumors. It is apparent that a range of nodular thyroid tissue using large tumor sample numbers is necessary to establish robust markers for malignancy and to categorize tumors on the basis of small tumor samples.

Radionuclide thyroid scanning of patients with Hashimoto’s thyroiditis (HT) may mimic other thyroid disorders including cold nodules, multinodular goiter and rarely hot nodules. The association of single hot nodules in such patients in the face of primary hypothyroidism has not been previously reported. We describe 6 female patients with HT who presented either with symptoms of overt thyroid failure or a sensation of lump in the neck (and later found to have mild thyroid failure) who had single firm thyroid nodules. These nodules were hot by both 99mTc pertechnetate and radioiodine thyroid scans. In three of 4 patients followed up for longer than 6 months on adequate thyroid replacement therapy the nodules regressed by up to 60%. Given “Best practice” recommendations patients with thyroid failure and single thyroid nodules would not be submitted to radionuclide scanning and this presentation of HT would have gone undetected.

We describe a kindred from Mauritius with an incomplete variant of multiple endocrine neoplasia type 1 (MEN 1Burin). In this family the syndrome is related to a novel MEN 1 gene mutation (deletion of A) at nucleotide 1021 of codon 304 resulting in frame shift and downstream protein truncation at codon 320. Compared to mainstream MEN 1, MEN 1Burin is characterized by a high prevalence of prolactin-secreting pituitary adenomas, late-onset of hyperparathyroidism and rare pancreatic involvement. The family described represents the fifth in the literature with the MEN 1 Burin phenotype; 2 out of the other 4 were related to R460X, Y312X respectively and no mutation within the coding sequence of MEN 1 was found in the other 2. Thus, similar to the classic syndrome, MEN 1Burin phenotype shows poor correlation to MEN 1 genotype.

We describe a woman with complete hypogonadotropic hypogonadism and a new compound heterozygous mutation of the GnRH receptor (GnRHR) gene. A null mutation L314X leading to a partial deletion of the seventh transmembrane domain of the GnRHR is associated with a Q106R mutation previously described. L314X mutant receptor shows neither measurable binding nor inositol phosphate production when transfected in CHO-K1 cells compared to the wild-type receptor. The disease is transmitted as an autosomal recessive trait, as shown by pedigree analysis. Heterozygous patients with GnRHR mutations had normal pubertal development and fertility. The present study shows an absence of LH and FSH response to pulsatile GnRH administration (20 microg/pulse, sc, every 90 min). However, GnRH triggered free alpha-subunit (FAS) pulses of small amplitude, demonstrating partial resistance to pharmacological doses of GnRH. FSH, LH, and FAS concentrations were evaluated under chronic estrogen treatment and repeat administration of GnRH. Not only were plasma FSH, LH, and FAS concentrations decreased, but FAS responsiveness was reduced. This new case emphasizes the implication of the GnRH receptor mutations in the etiology of idiopathic hypogonadotropic hypogonadism. We also have evidence for a direct negative estrogen effect on gonadotropin secretion at the pituitary level, dependent on the GnRHR signaling pathway.

In the pathomechanism of the thyroid associated ophthalmopathy (TAO) the inflammatory cytokines produced by infiltrating lymphocytes of the retroorbital tissues are involved. The activated lymphocytes have been shown to secrete a number of cytokines including tumour necrosis factor-alpha, interleukin-1 and interferon-gamma. The widely used immunosuppressive therapies have potential serious side effects. The pentoxifylline (Ptx) is known to have effect on production of cytokines. The aim of this study was to investigate the effect of Ptx on expression of HLA-DR molecules and production of glycosaminoglycan of human retroorbital tissue cultures and potential efficacy in patients with TAO. It was found that pentoxifylline (Ptx) was able to inhibit significantly the HLA-DR expression and glycosaminoglycan synthesis induced by inflammatory cytokines including TNF-alpha, IFN-gamma and IL-1. Ten patients with untreated moderate severe ophthalmopathy (8 female and 2 male) were excluded from steroid treatment due diabetes mellitus and psychiatric disease. Classification of eye changes was made by NOSPECS categories and total eye score. All patients were euthyroid during the study and was no remarkable difference in thyroid function and eye symptoms. Before and during Ptx therapy the laboratory parameters were also determined including glycosaminoglycan. TNF-alpha, anti-TSH-receptor, anti-eye muscle, anti-thyroglobulin and anti-thyroid peroxidase antibodies in the patients'sera. It was found a remarkable improvement in the eye symptoms in eight of ten patients. The levels of glycosaminoglycan (uronic acid) and TNF-alpha gradually decreased in eight patients who considered to be responders. The levels of uronic acid in plasma of the responders were found to be significantly lower after Ptx treatment. Before Ptx therapy the TNF-alpha in the sera was not different remarkably in non-responders and responders. After 4 weeks Ptx treatment the TNF-alpha decreased significantly in responders compared to non-responders (20.9 +/- 4.8 pg/ml v. s. 28.3 +/- 6.1 pg/ml) (p0.01). The titre of anti-eye muscle antibodies were found to be lower at the end of observation, however, the anti-thyroid antibodies were not changed remarkably. It was concluded that Ptx in the majority of patients (8/10) has a beneficial effect on inflammatory symptoms of TAO and laboratory parameters and suggested to use as an additive therapy, however, further comparative studies are required for final evaluation of Ptx in the treatment of TAO.

A chemiluminescence method was developed to measure thyroid peroxidase (TPO) activity and the inhibitory effect of anti-TPO antibodies in purified porcine TPO. The TPO preparation was characterized kinetically and controlled by Western-blotting technique. The chemiluminescence method proved to be reproducible and much more sensitive than the widely used guaiacol method, being able to detect TPO concentrations of 2.21 x 10(-5) g/L vs 6.63 x 10(-2) g/L with the latter. Otherwise, the determinations with the two methods correlated well (r = 0.76). Investigating the effect of IgGs from 23 hypothyroid patients on measured TPO activity, we detected inhibition in 19 cases with the chemiluminescence technique (15 with the guaiacol method). Anti-TPO antibodies showed competitive inhibition of TPO activity with respect to the substrate guaiacol. In both systems, the inhibition is present in the IgG F(ab')2 fragment. We conclude that the high sensitivity of chemiluminescence detection allows routine determination of the inhibition of TPO activity by anti-TPO antibodies.

Glycosaminoglycan (GAG) accumulation produced by retroocular fibroblasts (REF) has been observed in patients with thyroid-associated ophthalmopathy (TAO). Various cytokines are able to express HLA-DR molecules and stimulate the REF to proliferate GAG and free oxygen radicals. Pentoxifylline (Ptx) is known to have complex immunomodulatory effects on production of cytokines including interferon gamma (IFN-gamma). Ptx has been assumed to inhibit the cytokine-induced production of GAG and HLA-DR expression. We wished to determine whether Ptx has an effect on the IFN-gamma induced HLA-DR expression and influences the spontaneous and cytokine-induced GAG synthesis of REF. REF derived from extraocular muscles of healthy subjects were cultured without and with IFN-gamma. The effect of Ptx on expression of HLA-DR molecules and the production of GAG by REF was determined. Glycosaminoglycan was measured by incorporation of (3H)glycosamine into GAG. HLA-DR expression was analysed by fluorescence activated cell sorter. IFN-gamma (50, 100 and 500 U/ml) induced an increase in expression of HLA-DR molecules of REF. Ptx was proved not to be toxic for cultured cells. This drug was able to dose-dependently inhibit HLA-DR expression of REF. Both spontaneous and IFN-gamma-induced GAG synthesis of REF was inhibited by Ptx (100, 500 and 1000 mg/l, respectively). Due to in vitro inhibitory effects, Ptx is potentially able to modify the antigen presentation and the GAG synthesis by REF and it might be a useful therapeutical drug in the treatment of TAO.

The authors previously found p53 mutations in 24% of malignant thyroid tumors, representing a wide stating spectrum. Overexpression of MDM2, most often due to gene amplification, has been suggested to be an additional mechanism for abrogation of the p53 function. In the current study, MDM2 gene expression and amplification were examined in a randomly selected subset of these tumors to explore the possibility that wild-type p53 may be inactivated by complexing with MDM2 in specimens without p53 mutations.MDM2 gene expression and amplification were studied by Northern and Southern blot analysis, respectively. Twenty-two thyroid tumors were included: 16 papillary carcinomas, 1 follicular carcinoma, 3 anaplastic carcinomas, and 2 multinodular goiters (adenomatous goiters).A two- to threefold increase in MDM2 expression in 4 of 20 thyroid carcinomas was found. It was noteworthy that all of these four samples harbored p53 mutations. The association between increased MDM2 expression and p53 mutation was statistically significant (P0.005). No evidence of MDM2 gene amplification or rearrangement accounting for such an increase in MDM2 expression was found.Genetic and/or environmental factors contributing to random p53 mutations also may cause increased MDM2 expression. Given the moderate increase in MDM2 expression without associated genetic alterations such as gene amplification and rearrangement, MDM2 may not play any significant role in the development and progression of thyroid carcinoma.

Using polymerase chain reaction and sequence-specific oligonucleotide hybridization, the frequency of three ras oncogene mutations (N-ras, Ha-ras, and K-ras) in thyroid tumors (25 adenomas, 16 follicular carcinomas, and 22 papillary carcinomas) was investigated in both iodide-deficient and iodide-sufficient areas. The ras oncogene mutation rate was significantly higher in the iodide-deficient area, being 85 versus 17% in the adenomas, and 50 versus 10% in the follicular carcinomas. No mutations were found in papillary carcinomas. The most common mutation site was Ha-ras codon 61 with Gln----Arg substitution. Two ras mutations at codon 61 (Gln----Lys in N-ras and Gln----Arg in Ha-ras) were found in a microfollicular adenoma specimen from Eastern Hungary. We conclude that dietary iodine may modulate ras oncogene mutations, and that in the iodide-deficient area, ras oncogene activation may play a more important role in the initiation and/or maintenance of follicular tumors. Additional factors are, however, necessary to initiate carcinogenesis.

75 patients with Graves' disease (54 with ophthalmopathy) were investigated using the tests of leucocyte adherence inhibition and immune adsorption with 125I-labelled Staphylococcus Protein A, against human eye muscle "crude" membrane antigen. The results of positive leucocyte adherence inhibition (10 out of 26 vs. 1 out of 28, P less than 0.05) and anti-human eye muscle membrane antibody index (mean +/- S.D.) (1.89 +/- 1.20 vs. 0.84 +/- 0.38, P less than 0.001) showed a correlation with the patients with clinically active eye disease and the HLA-B8 antigen in Graves' ophthalmopathy (P less than 0.01). Positive leucocyte adherence inhibition was observed in 9 out of 21 cases of Graves' disease without ophthalmopathy, but its prognostic relevance has to be confirmed in the development of ophthalmopathy.

Three mAb to variable region determinants of the alpha/beta-chain TCR were used to detect discrete populations of peripheral blood T cells. T cells sharing a TCR determinant defined by such an antibody presumably use the same or similar TCR V or J genes for their alpha- or beta-chains. Thus analysis with these mAb provides a tool to investigate TCR gene usage and expression. Since autoantigen specific T cells may play an important role in initiating autoimmune diseases, TCR were analyzed in different autoimmune diseases and control groups including rheumatoid arthritis, Graves disease, idiopathic thrombocytopenic purpura, psoriasis, SLE, insulin-dependent diabetes mellitus, and in nonautoimmune control diseases and normals. Purified T cells were stained by indirect immunofluorescence with three mAb to TCR variable regions: mAb S511 stains 1.8 +/- 0.9% (mean +/- 2 SD), mAb C37 stains 3.4 +/- 1.5% and mAb OT145 stains from 0 to 6% of T cells from normal donors. Several individuals were identified with expanded subsets of positive T cells. One patient with adult ITP followed during a 12-mo period consistently had elevated percentages of T cells staining with the mAb OT145 (15.9 to 24.5%). These cells were found to be exclusively CD8+. By Southern blotting DNA prepared from these OT145+, CD8+ cells, but not DNA from the patient's OT145- T cells, revealed a clonal rearrangement using a beta-chain C region probe. Thus this patient had a monoclonal expansion of CD8+, OT145+ cells. Hyperexpression of a TCR variable region, as defined by the available mAb, could not be associated with any of the diseases studied. Examination of T cells at the site of autoimmunity, such as T cells from rheumatoid arthritis synovial fluid, revealed normal percentages of cells staining with these mAb. Immunoperoxidase staining of psoriatic lesional skin showed no striking enrichment of T cells bearing one or the other TCR type.

We typed coded sera from 135 healthy controls, seventy-six patients with autoimmune goitrous and seventy-three with atrophic thyroiditis for IgG heavy chain markers (Gm). All subjects were Caucasian from Newfoundland. An increase in the Gm phenotype ag was found in the 149 patients with thyroiditis compared to controls (chi 1(2) = 5.82, P less than 0.01); significance was, however, not maintained after correction for the number of variables tested. The difference in ag phenotype was more pronounced among the seventy-three patients with atrophic thyroiditis (chi 1(2) = 8.80 corrected P less than 0.05). Because the haplotype ag was not significantly increase in this group, we conclude that homozygotes for Gm ag are at an increased risk of developing atrophic thyroiditis.

On the premise that an antibody combining site is a mirror image of its antigen epitope, it is expected that an anti-idiotypic antibody (i.e., an antibody specific for the combining site of the first antibody) will be homologous to the epitope. Anti-idiotypic antibodies raised against hormones or drugs would, therefore, be anticipated to interact with their respective receptors. According to this schema, anti-idiotypic antibodies could either be antagonists or agonists. Most of the anti-idiotypic antibodies raised against hormones and neurotransmitters to date have proved, however, to be agonists. We have raised antithyrotropin (anti-TSH) anti-idiotypic antibodies and found these to interact with the high affinity binding site for TSH on thyroid plasma membranes and to induce cGMP-dependent adenylate cyclase activation and iodide transport into dispersed thyroid cells, as well as to promote their organization into follicular structures. The anti-TSH anti-idiotypic antibody interacted with a holoreceptor band of relative mass (Mr) ~ 200 000, resolved on sodium dodecyl sulfate – polyacrylamide gel electrophoresis from thyroid membranes and transferred to nitrocellulose paper. In another set of experiments we raised anti-idiotypic antibodies against monoclonal antibodies specific, respectively, for the α and β subunits of TSH. Neither the α nor β monoclonal antibody specific anti-idiotypic antibodies interacted with the TSH holoreceptor. The combinations of the two anti-idiotypic antibodies, however, did so and increased basal cyclase activity significantly compared with normal immunoglobulin G. As a result of the second set of experiments, we propose that the interaction of TSH with its receptor involves two signals delivered by the two subunits rather than a single signal requiring their combination. Anti-idiotypic antibodies raised against highly purified hormones can be obtained in large amounts. They facilitate simple isolation of hormone receptors and are useful as probes for hormone–receptor interactions.

We studied the diallelic system HLA--Bw4/w6 in patients with Graves' disease and control subjects. Twenty-one out of the 22 patients with Graves' disease were found to be HLA--Bw6 positive and 16 of these were homozygous, contrasted with 28 and 9 out of 34 controls, respectively. HLA--Bw6 positivity results in a relative risk for Graves' disease of 3.27; homozygosity for that allele further increases the risk to 7.4. It is possible that the increased risk attached to HLA--Bw6 is secondary to the increase in HLA--B8 previously described in Graves' disease.

In view of the reported variation in the association between HLA antigens and Juvenile Diabetes Mellitus (J.D.M.) among different Caucasian populations, we have undertaken a study of these antigens among 44 Caucasian Newfoundlanders and 135 matched controls. We have also studied the allotypic markers for Immunoglobulin G (Gm) and variants of C3 among 36 of these patients. We found that both HLA--B8 and B15 were increased among the patient group, resulting in a relative risk of 3.9 and 4.4 respectively. While these values are the highest to be described for J.D.M. among Caucasians, and fell outside the 95% confidence intervals for the combined relative risk calculated from published series, it is still possible that they can be accounted for by sampling. The combination of the two antigens increased the relative risk for J.D.M. in an additive fashion. Additionally, we also found that the combination of HLA B8 and B18, but not B15 and B18, also appear to act in an additive manner. The incidence of Gm allotypes and variants of C3 were not different in the J.D.M. group from those observed among controls.

We assessed the efficacy of a new thyroxine radioimmunoassay kit (Abott) in which polyethylene glycol is used to separate bound from free hormone. Mean serum thyroxine was 88 +/- 15 (+/-SD) microgram/liter for 96 normal persons. Results for hypothyroid and hyperthyroid persons were clearly separated from those for normal individuals. Women taking oral contraceptive preparations showed variable increases in their serum thyroxine values. The coefficient of variation ranged from 1 to 3% within assay and from 5.4 to 11% among different assays. Excellent parallelism was demonstrated between thyroxine values estimated by this method and those obtained either by competitive protein binding or by a separate radioimmunoassay for the hormone.

We assessed the efficacy of a new thyroxine radioimmunoassay kit (Abott) in which polyethylene glycol is used to separate bound from free hormone. Mean serum thyroxine was 88 +/- 15 (+/-SD) microgram/liter for 96 normal persons. Results for hypothyroid and hyperthyroid persons were clearly separated from those for normal individuals. Women taking oral contraceptive preparations showed variable increases in their serum thyroxine values. The coefficient of variation ranged from 1 to 3% within assay and from 5.4 to 11% among different assays. Excellent parallelism was demonstrated between thyroxine values estimated by this method and those obtained either by competitive protein binding or by a separate radioimmunoassay for the hormone.

Influence of lithium on luminol amplified chemiluminescence activity of leucocytes of human peripheral blood was studied by a continuously recorded system. Lithium had a biphasic effect on mitogen-induced early activation of mononuclear cells, i.e. at concentration of 1.0 mM an increase, at higher concentrations a significant inhibition in photon emission was observed. Activating the mononuclear cells by opsonized Zymosan in the presence of lithium a dose-dependent decrease of chemiluminescence was registered. The respiratory burst of polymorphonuclear granulocytes induced by either mitogen or opsonized Zymosan was significantly inhibited at 2.0 and 5.0 mM of lithium, respectively. Chemiluminescence activity of peroxidase-dependent and independent cell-free system was not influenced by lithium. It was concluded that lithium by accumulating into target organs might have an immunosuppressive and antiphlogistic effect by mean of inhibition of antigen-presenting cells and polymorphonuclear granulocytes.

SUMMARY We have examined the combined usefulness of TSH-receptor antibody detection and HLA status on the therapeutic response to standard doses of radioactive iodine (RAI) in forty-three hyperthryoid Graves’patients. Twenty-three patients had detectable TSH-receptor antibodies as measured by 125I-TSH binding-inhibition (TBI) prior to administration of 7 mCi RAI. Eighteen (78%) of these patients were rendered euthyroid within 3 months. In contrast, twenty patients were TBI negative prior to RAI and sixteen (80%) of these individuals remained hyperthyroid at 3 months and required two, or more, doses of RAI to control their thyroid function. DR3 status alone was not strongly associated with resistance to RAI. However, of sixteen patients without detectable TBI activity and who required two or more doses of RAI, ten patients were DR3 positive (62%) compared with 25% in a control population. Only one patient who was both TBI and DR3 negative required more than one dose of RAI. These data indicate that TBI may be an accurate predictor of the therapeutic response to RAI in patients with hyperthyroid Graves’disease. Investigation of HLA status alone was of limited value, although it appeared that the combination of TBI and DR3 may be of additional help in developing an overall strategy for the treatment of hyperthyroid Graves’disease.

Three mAb to variable region determinants of the alpha/beta-chain TCR were used to detect discrete populations of peripheral blood T cells. T cells sharing a TCR determinant defined by such an antibody presumably use the same or similar TCR V or J genes for their alpha- or beta-chains. Thus analysis with these mAb provides a tool to investigate TCR gene usage and expression. Since autoantigen specific T cells may play an important role in initiating autoimmune diseases, TCR were analyzed in different autoimmune diseases and control groups including rheumatoid arthritis, Graves disease, idiopathic thrombocytopenic purpura, psoriasis, SLE, insulin-dependent diabetes mellitus, and in nonautoimmune control diseases and normals. Purified T cells were stained by indirect immunofluorescence with three mAb to TCR variable regions: mAb S511 stains 1.8 +/- 0.9% (mean +/- 2 SD), mAb C37 stains 3.4 +/- 1.5% and mAb OT145 stains from 0 to 6% of T cells from normal donors. Several individuals were identified with expanded subsets of positive T cells. One patient with adult ITP followed during a 12-mo period consistently had elevated percentages of T cells staining with the mAb OT145 (15.9 to 24.5%). These cells were found to be exclusively CD8+. By Southern blotting DNA prepared from these OT145+, CD8+ cells, but not DNA from the patient's OT145- T cells, revealed a clonal rearrangement using a beta-chain C region probe. Thus this patient had a monoclonal expansion of CD8+, OT145+ cells. Hyperexpression of a TCR variable region, as defined by the available mAb, could not be associated with any of the diseases studied. Examination of T cells at the site of autoimmunity, such as T cells from rheumatoid arthritis synovial fluid, revealed normal percentages of cells staining with these mAb. Immunoperoxidase staining of psoriatic lesional skin showed no striking enrichment of T cells bearing one or the other TCR type.

Fibrinolytic activity and factor VIII concentration were studied in 30 patients with moderate to minimal hypothyroidism and in 7 patients with hyperthyroidism. In the hypothyroid group, the results were related to serum thyroxine levels, HL-A phenotypes and thyroid autoantibody titres. As serum thyroxine decreased so did factor VIII concentration, however, euglobulin lysis time was correspondingly prolonged. Factor VIII appears to be the most sensitive among coagulation factors to the deterioration of thyroid function tests. There was a significant correlation between the reciprocal of thyroid antibody titres and fibrinolysis; however, there was no relationship between factor VIII concentration or fibrinolysis and a specific HL-A phenotype although the incidence of HL-A8 was increased in the group as a whole. Euglobulin lysis time was prolonged in 6 out of 7 patients with Graves' hyperthyroidism. Factor VIII was elevated in only 3 of these patients.

SUMMARY The Gm phenotype Gm f,b or Gm f,n,b was found in all forty patients with Graves' disease studied, contrasted with thirty-five out of forty controls and twenty out of thirty-one patients with thyroiditis. The difference between the two groups with autoimmune thyroid disease was significant. These results suggest that thyroid stimulating antibodies may be allotypically restricted.

Graves' disease is associated with HLA-DR3 in Caucasoids. We have now demonstrated, on the basis of disease-associated MHC haplotypes (A1, Cw3, B8, DR3 and fragments thereof) from 38 families in which more than one member had Graves' disease compared with MHC haplotypes from 56 healthy families, that the risk was highest with the DR locus (relative risk for A1, B8, DR3 = 2.3, for B8, DR3 = 5.3, and for DR3 = 6.8). We further used the sib-pair method to explore linkage of Graves' disease liability to the MHC in 67 affected sib-pairs. The data were consistent with an MHC-linked recessive gene with a frequency of 0.2 to 0.3 and a penetrance of 7.2%; the data, however, accommodated penetrance of up to 16.3%. A recessive model was also consistent with the HLA-B8 genotype distribution in 286 unrelated patients. As the effect of the marker alleles on the course of the disease had been debated several times, we applied a cluster analysis method using 49 clinical and laboratory characteristics, including the HLA-A and HLA-B antigens of 196 patients. Three groups were identified, corresponding to patients with mild disease, Hashitoxicosis and severe (relapsing) disease. The prevalence of HLA-B8 was 8.9%, 21% and 87%, respectively (compared to 18.8% in 380 controls). This suggests the existence of an underlying continuum of genetic liability, apparently related to that for Graves' disease severity, associated with the MHC and mediated through immunoregulatory disturbances.

Ninety-eight members of a large Newfoundland family, seven of whose members over three generations suffered from Graves' disease, were studied with respect to the mode of transmission of the disease and its association with HLA. Compared to Newfoundland communities of similar size and geographical location, very little consanguinity was documented in this family. The susceptibility to Graves' disease appeared to be inherited as a dominant with a variable degree of expressivity; the degree of expressivity being determined by the female sex. In part of the pedigree, the susceptibility to Graves' disease entered the family with a wife. Three of her offspring who subsequently developed Graves' disease shared with her the haplotype A9, Bw16. Of the three remaining affected family members, two shared the haplotype A1, B8, whereas the third carried the haplotypes Aw32,b8; a9,bw16. Graves' disease could be associated with either of these two haplotypes in the last individual. This study shows that the susceptibility to Graves' disease is inherited associated with HLA and that whereas the disease susceptibility gene for Graves' disease is in linkage disequilibrium with HLA-B8 in Caucasians, it can be randomly associated with other HLA-B antigens.

We have extended our study of an incomplete variant of multiple endocrine neoplasia Type I (MEN IBurin). In this syndrome, primary hyperparathyroidism and prolactin-secreting adenoma are common, with hormone-secreting pancreatic tumors being rarely seen. The recent localization of the prolactin structural gene to chromosome 6 made further investigation of linkage to HLA of particular interest. Results in 2 multigeneration families exclude close linkage to HLA. We cannot at this time draw any inference regarding linkage of MEN IBurin to the prolactin structural gene.

Evidence concerning the role of hyperthyroidism per se in suppressor cell dysfunction in Graves' disease is conflicting. To investigate this issue, we studied the effect of triiodothyronine (T3) administration to ten healthy volunteers for 7 days on spontaneous (short-lived) and Concanavalin A (Con A)-induced suppressor cell activities. The short-lived suppressor cell index is a ratio of [3H] thymidine incorporation induced by Concanavalin A in lymphocytes preincubated for 24 h (to remove adherent cells) to that of non-incubated lymphocytes; the more active the adherent suppressor cells, the higher this index. The mean short-lived suppressor cell index rose from a mean of 2.46 +/- 0.15 (+/- S.D.) before T3 treatment to 3.29 +/- 0.46 (p less than 0.01) after 7 days of T3. Concanavalin A-induced suppressor cell activity, which measures the potential suppressive activity of lymphocytes triggered by Con A is expressed as the percentage decrease in [3H] thymidine incorporation by lymphocytes cultured with Con A for 72 h in relation to that by fresh lymphocytes. Con A-induced suppressor cell activity also improved from 55.8% +/- 2.5 before T3 treatment to 62.4% +/- 1.9 (p less than 0.05) at 7 days of this treatment. These studies show that within the time limitations of the study, T3 appears to enhance short-lived and Concanavalin A-induced suppressor cell activities.

Summary The hyperthyroidism of Graves' disease is thought to be related to antithyrotropin receptor (TSH-R) antibodies. In order to study the degree of immunogenetic homogeneity of these antibodies, we carried out Gm typing of ‘receptor-purified’ IgG from patients with active Graves' disease and controls. The results were compared to those of serum, total IgG and IgG which failed to attach to TSH-R. We found that in five out of seven Gm heterozygote patients studied the receptor-purified antibodies were restricted to the products of one haplotype compared to three out of five similar controls. Such eluted antibodies were biologically active. Similar results in terms of immunogenetic restriction and activity were obtained when F(ab)2 preparations were used. An unexpected finding was that sera and IgG from normal persons attached to thyroid membranes and that the attachment occurred via F(ab)2. Normal whole serum and ‘receptor-purified’ IgG and F(2 inhibited TSH binding in the receptor assay; however, this inhibition showed no specificity for TSH-R.

In an Eastern Hungarian population of patients, we sought to confirm an association with IgG heavy-chain allotypes (Gm) with Graves' disease. We found an increase in the phenotype fb (chi 2(1) = 4.7, p less than 0.05) among the patient group compared to controls. The influence of Ig-linked genes to Graves' disease susceptibility is, thus, dose-dependent. We found no interaction between fb homozygosity and HLA-DR3 positivity in Graves' disease susceptibility.