Human T-lymphocyte subpopulations in Hashimoto's disease.

An inherited defect os suppressor T-lymphocytes has been hypothesized in Hashimoto's thyroiditis. To assess this hypothesis, human T-lymphocyte subsets (TG, T lymphocytes with surface receptors for the Fc fragment of immunoglobulin G; TM, T lymphocytes with Fc receptor for immunoglobulin M) have been studied in nine patients affected by the disease. To cells have been previously shown to be suppressors in the pokeweed mitogen-stimulated B-cell differentiation and have proved abnormal in several autoimmune or immunodeficiency disorders. The number of TG lymphocytes in the patients did not differ from that in normal controls. It is possible that 1) suppressor T-lymphocytes are not involved in the pathogenesis of Hashimoto's disease or 2) antigen-specific suppressor T-cells are involved, but too are low in number with respect to total TG.

[Unusual clinical aspects of hyperthyroidism. Apathic hyperthryroidism]. / Aspetti clinici rari dell'ipertiroidismo. L'ipertiroidismo apatico.

The principal data in the literature regarding apathic hyperthyroidism are summarised and commented on 3 personal cases are then reported. The nosography of these forms is discussed and emphasis laid on pathogenetic hypotheses and diagnostic and therapeutic aspects. Diagnosis should be precise and early so as to prevent the extremely serious course which is a characteristic of this rare, but not exceptional variant of hyperthyroidism.

Adrenal gland photoscanning by means of 131I-iodinated cholesterol.

Photoscanning by means of 131I-19-iodinated cholesterol was performed on 10 patients with various diseases of the adrenal glands. The authors confirmed that the method was suitable for study of the morphology and function of the adrenal glands in disease, especially when combined with stimulation by ACTH or suppression by dexamethasone. The radiation dose absorbed by the thyroid and by the gonads can be controlled during the examination by blocking the iodine trapping and suppression of the gonado-stimulating action, respectively.

Twenty-four hour profile of integrated TSH concentration in puberty.

The 24-h pattern of integrated serum TSH concentrations has been investigated in 12 healthy adult males and 14 pubertal boys by means of continuous blood flow sampling. For every subject the integrated values and the mean concentrations, corresponding to the entire 24 hours, to the daytime (08:00-20:00) and to the nighttime (20:00-08:00) were calculated. A circadian rhythmicity has been shown in boys, as well as in adults. The mean TSH concentrations were significantly higher in boys with respect to adults. The nyctohemeral maximum was mostly recorded in pubertal boys after sleep and in adults before the onset of sleep. Mean and integrated concentrations corresponding to the nighttime period were significantly higher than those corresponding to the daytime in both groups. In conclusion, the 24-h TSH secretion seems different in boys with respect to adults both in the increased concentrations and in the time (generally after the onset of sleep) of the maximum.

Terfenadine (single or associated) treatment of adverse reactions to foods.

Six groups of patients (total 105), affected by cutaneous signs and symptoms related to food ingestion were studied with regards to the clinical efficacy of some pharmacologic treatments: blind placebo, terfenadine alone, terfenadine associated with pirenzepine or rosaprostol or ranitidine or famotidine. Pharmacologic treatment by terfenadine alone showed poor clinical results, similar to placebo, while the associations of terfenadine with both cytoprotective drugs and anti-H2 receptor antagonists revealed significant clinical improvement which is more evident in those patients treated with cytoprotective drugs combination than those who were treated with anti-H2 antagonists.

Circulating T cell subsets in euthyroid Graves' disease.

T cell subpopulations recognized by surfaces markers of different functional meaning have been evaluated in 12 female patients with euthyroid Graves' disease and in 2 patients with ophthalmopathy and Hashimoto's thyroiditis. We have used the following markers: i) receptors for Fc fragments of IgG; ii) antigens recognized by the monoclonal antibodies MLR4, 5/9, BT 2/9 (anti-DR). In the 12 patients with euthyroid Graves' disease a marked decrease of TG cells (which proved to exert suppressor function in several in vitro systems) was observed, as previously reported in hyperthyroid Graves' disease. The 2 Hashimoto's patients with eye changes had normal or high TG. 5/9+ T cells (which contain cells with helper activity in vitro), as well as MLR4+ and BT 2/9+ cells (activated T cells) were normal in the majority of patients, but elevated in the 2 Hashimoto's thyroiditis. The observed abnormality of TG cells in euthyroid Graves' disease might be consistent with the hypothesized autoimmune pathogenesis of endocrine ophthalmopathy.

T lymphocyte subpopulations in Graves' disease: relationship with clinical conditions.

T lymphocytes were fractionated according to their receptors for IgG (TG) or IgM (TM) and scored in 37 patients with Graves' disease (17 hyperthyroid and untreated. 10 euthyroid on antithyroid drugs, 10 in long-term remission after radioiodine therapy). TG percentages were very low both in untreated and in drug-treated patients. By contrast, normal TG levels were observed in patients in long-term remission. These data are consistent with the hypothesis of a defective suppressor cell activity in Graves' disease.

Deficiency of the autologous mixed lymphocyte reaction in patients with autoimmune thyroid disease.

The proliferative response of T lymphocytes when cocultured with autologous non-T cells in the absence of any other stimulating substance has been termed the autologous mixed lymphocyte reaction (AMLR). The AMLR has been shown to be impaired in several autoimmune disorders, such as systemic lupus erythematosus, Sjögren's syndrome, and primary biliary cirrhosis. In this study we report marked deficiency in the AMLR in two autoimmune disorders: Hashimoto's and Graves' diseases. This impaired AMLR, probably related to previously described T cell subset imbalances, provides further evidence of altered interactions between the immunocompetent cellular subsets in patients with these pathological conditions. Additional preliminary observations suggest defective allogeneic mixed lymphocyte reactions as well.

Thyroglobulin-induced T-cell in vitro proliferation in Hashimoto's thyroiditis: identification of the responsive subset and effect of monoclonal antibodies directed to Ia antigens.

Recently it was reported that the peripheral blood and thyroid gland of patients with Hashimoto's thyroiditis contain activated (Ia+ and/or MLR4+) T cells and high levels of 5/9+ ("helper") T lymphocytes. In normal individuals the 5/9 monoclonal antibody recognizes a T-cell fraction that includes all T lymphocytes with inducer activities. Here, circulating 5/9+ and 5/9- T lymphocytes were isolated from patients with Hashimoto's disease, and the proliferative response induced by human thyroglobulin was investigated. The results show that the total thyroglobulin-induced lymphocyte DNA synthesis is confined to the 5/9+ T-cell fraction. Further subfractionation of 5/9+ into MLR4+ and MLR4- cells clearly indicates that no substantial differences exist in their proliferative capacities. Whether 5/9, MLR4, and Ia antigens, all expressed on the thyroglobulin-responsive T-cell subset, are involved in thyroglobulin-induced cell proliferation, was also analyzed. Although both 5/9 and MLR4 monoclonal antibodies had no effect, complete inhibition of antigen-induced blastogenesis was observed upon addition of monoclonal antibodies (D1/12 and BT2/9) directed to common determinants of Ia antigens. This inhibitory effect was also observed when T or non-T fractions were separately incubated with the monoclonal antibodies before culture. These results indicate that in humans, as in animals, the major histocompatibility complex may play a role in autoimmune thyroiditis. The data show that (a) the thyroglobulin-induced proliferative response is confined to a subset (5/9+) of T lymphocytes and (b) Ia antigens are involved in thyroglobulin-induced lymphocyte DNA synthesis in Hashimoto's disease.