Serial serum thyroglobulin measurements in the management of differentiated thyroid carcinoma

Serum thyroglobulin (Tg) was measured on repeated occasions in 416 patients with differentiated thyroid cancer for up to 7 years after initial therapy. All patients had thyroidectomy and/or ablative 131I therapy and all measurements were done while patients were receiving T4 replacement. Tg was measured using a double-antibody radioimmunoassay. Overall correlation between serum Tg concentration and presence or absence of cancer was 95.9%. At the time of initial measurement 295 patients had serum Tg less than 5 micrograms/l, and in latest analysis only 1.7% of these patients showed evidence of disease. Initially there were 19 patients of a total of 121 with serum Tg greater than 5 micrograms/l in whom no cancer was apparent. In eight of these 19 subjects recurrent or metastatic disease has been diagnosed up to 3.5 years after the first measurement indicating that in these cases serum Tg values were 'predictive'. Serum Tg appears to be a sensitive and specific means of detecting residual, recurrent or metastatic thyroid cancer and in most situations can replace routine, expensive and inconvenient radioactive thyroid scans; these should be performed when serum Tg values are elevated or when there is clinical evidence suggesting recurrence.

Reduced serum thyroglobulin response to bovine TSH in malignant hypofunctioning solid thyroid nodules: comparison to benign nodular disease

Forty-three euthyroid patients with a single, solid, nonfunctioning thyroid nodule were submitted to fine needle aspiration biopsy and serum thyroglobulin (Tg) was measured before and after (48h) 10 U of bovine TSH. Twenty-two normal subjects were also submitted to the bTSH test. Patients with nonfunctioning nodules were divided in two groups: (I) Benign or Suspicious Cytology (n = 32), (II) Malignant tissue (n = 11). In the latter group all patients underwent surgery and the pathology findings confirmed the presence of thyroid carcinoma. Twenty-one patients with benign or suspicious cytology were also operated upon and the diagnosis was colloid goiter (n = 16) and follicular adenoma (n = 5). In eleven other patients the nodule reduced significantly in size (8) or was no longer palpable after suppressive therapy (3). Normal individuals had a basal serum Tg mean +/- SD value of 12 +/- 7.2 ng/ml and a peak Tg value of 44 +/- 47 ng/ml. Serum Tg values were significantly higher (p less than 0.01) in patients with benign and malignant nodules. However the mean absolute increment (delta Tg) after bTSH was significantly lower (p less than 0.01) in patients with malignant nodules (7.2 +/- 4.8 ng/ml) as compared with normal subjects (22 +/- 16 ng/ml) or subjects with benign nodules (31 +/- 30 ng/ml). The relative (%) serum Tg increment was also significantly lower in patients with malignant tissues (14 +/- 11) as compared to those with benign nodules (77 +/- 86) or normal subjects (247 +/- 173).(ABSTRACT TRUNCATED AT 250 WORDS)

Separation and analysis of mononuclear cells infiltrating the thyroid of patients with Graves' disease

A simple method was established for separating lymphocytes infiltrating the thyroid from thyroid epithelial cells. Namely, suspensions of minced thyroid from patients with Graves' disease were layered on a Percoll two-step density gradient (p = 1.050 and 1.077 g/ml) and centrifuged (400g, 30 min, 4 degrees C). In this way 0.1-18 X 10(5) lymphocytes/g of thyroid tissue with a purity of 65-95% were obtained. Thyroid lymphocytes were analyzed quantitatively with monoclonal antibodies by laser flow cytometry and compared with peripheral lymphocytes. The proportion of OKT3+ cells was decreased with increase in OKIa+ cells. The percentage of OKIa+ cells was significantly correlated with that of Leu12+ cells. The percentages of OKT4+ cells and OKIa+ cells were higher when analyzed with an extended gate window, which was arranged for detection of activated, large-sized lymphocytes. The percentages of OKT8+ and Leu7+ cells were not significantly different from those in peripheral blood. From these results it was concluded that the proportion of B lymphocytes is increased and that of T lymphocytes is decreased, the proportion of activated B lymphocytes is increased, some helper/inducer T cells are activated in the thyroid gland in Graves' disease, and these activated lymphocytes may be important in local production of antithyroid autoantibodies.

Cellular and humoral immunity in patients with hyperthyroid Graves' disease before, during and after antithyroid drug treatment

Many reports of thyroid stimulating immunoglobulins (TSI) in relation to treatment of Graves' disease have been published and with variable results concerning prediction of permanent remission or relapse after therapy. A range of methods has been used and little has been published measuring TSI by using their ability to stimulate cyclic AMP production in human thyroid cells in monolayer culture. We therefore conducted a prospective study of the predictive value of such an assay in patients with hyperthyroid Graves' disease before, during and after treatment of one year with methimazole and thyroid hormone substitution. Furthermore, the possible relationship between activated suppressor T lymphocytes and TSI in patients followed before, during and after medical therapy has been studied. Patients were divided into two groups; group I, 15 patients, who stayed in remission and group II, 14, who relapsed during the first year after discontinuation of therapy. Mean TSI activity did not differ between the two groups before and during the first half year of medication. In the second half year of treatment, however, mean TSI activity was significantly lower in group I. TSI activity at the end of treatment appeared to have no value in predicting final outcome. Increased TSI activity in group II during treatment was reflected in an increased pertechnetate thyroidal uptake as compared to that in group I. There was no relationship between changes in TSI activity and T cell subsets (Leu 1, 2a, 3a). We found no difference in T lymphocytes between the two groups at any time during observation. Subsets of T lymphocytes in both patient groups did not differ from normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased incidence of true type I diabetes acquired during pregnancy

A longitudinal study was carried out of all patients with newly acquired insulin dependent diabetes during pregnancy (as distinct from non-insulin-dependent gestational diabetes) seen at the Copenhagen Centre for Diabetes and Pregnancy during 1966 to 1980. The series comprised 63 patients with a mean age of 27 (SEM 1) years. At diagnosis the mean fasting blood glucose concentration was 15.6 (1.3) mmol/l and mean maximal insulin dose 49 (3) IU/day. At a prospective follow up examination a mean of 8 (SEM 1) years after diagnosis 46 of 60 patients (77%) were being treated with insulin (35 (2) IU/day) and had a very low mean stimulated plasma C peptide value (0.12 (0.02) nmol/l) suggesting absent or nearly absent beta cell function. The remaining 14 patients (23%), not currently receiving insulin, appeared to be severely glucose intolerant, having a mean fasting blood glucose concentration of 13.4 (1.2) mmol/l. Thus most of these patients developing insulin dependent diabetes during pregnancy had true type I disease. Compared with the age specific incidence of type I diabetes in the background population of women the incidence was at least 70% higher in pregnant than non-pregnant women (p less than 0.001; chi 2 = 11.6; f = 1). This increased incidence occurred in the third trimester when the risk of developing type I diabetes was 3.8 times that of non-pregnant women (p less than 0.000001; chi 2 = 35.6; f = 1). Finally, the risk of developing insulin dependent diabetes during pregnancy was lower when conception occurred in the winter (p less than 0.05; chi 2 = 4.18; f = 1).

A sensitive enzyme immunoassay for anti-thyroglobulin antibody using Fab'-horseradish peroxidase conjugate. Evaluation of in vitro anti-thyroglobulin antibody synthesis by lymphocytes from patients with autoimmune thyroid disease

A sensitive enzyme immunoassay (EIA) for the detection of anti-thyroglobulin (Tg) antibodies was developed using Fab'-horseradish peroxidase (HRP) conjugate. Anti-Tg antibody was assayed by incubation with a thyroglobulin-coated polystyrene ball and then with affinity-purified anti-IgG Fab'-HRP conjugate. The HRP activity was assayed fluorimetrically. The sensitivity was 625 amol/tube and anti-Tg antibody levels between 0.5 and 200 ng/ml could be determined. The recoveries of anti-Tg antibody added to human sera at three different concentrations were 94.2-101.0%. Both within- and between-assay coefficients of variation were below 10%. Significant correlation was observed between values by the EIA and TGHA method (Kendall's rank correlation coefficient = 0.712, P less than 0.001). The present EIA for anti-Tg antibody is sensitive enough to determine anti-Tg antibody synthesized in vitro by the lymphocytes from patients with autoimmune thyroid disease and normal subjects. The amounts of anti-Tg antibody synthesized by peripheral lymphocytes from patients with Hashimoto's disease were significantly greater than those from patients with Graves' disease, although serum levels of anti-Tg antibody were usually elevated in both groups of patients. The results obtained suggest that anti-Tg antibody is synthesized in a different manner in patients with Hashimoto's disease and in patients with Graves' disease.

Role of growth hormone in regulating T-dependent immune events in aged, nude, and transgenic rodents

Growth hormone (GH) appears to play a major role in a reciprocal axis that has been postulated between the thymus and pituitary glands. Our previous studies showed that thymic structure, as well as T-cell proliferation and IL-2 synthesis, could be restored in aged female Wistar-Furth rats by the implantation of GH3 pituitary adenoma cells. These cells secrete GH and some prolactin. We have now used three different approaches to determine whether GH affects a variety of immune events in vivo in both old and young rodents, and whether GH3 cells can directly affect progenitor T-cells in nude rats that congenitally lack a thymus gland. To test the effects of GH in aged rats, 750 micrograms of pituitary-derived ovine GH was injected 2 x daily into 26-month-old Fischer 344 rats for 5 weeks. This approach demonstrated that GH augments splenocyte proliferation to T-cell lectins as well as natural killer (NK) activity at low effector:target ratios even though morphologic characteristics of the thymus were not altered. To assess the effect of GH in young rodents, mice were studied that were transgenic for the rat metallothionein-GH gene. Histologic evaluation of thymus glands revealed that the amount of adipose tissue and the number of epithelial cells and Hassall's corpuscles are augmented in transgenic mice. Splenocyte proliferation at suboptimal mitogen doses is greater in transgenic than in control littermate mice, but neither IL-2 synthesis nor antibody synthesis to sheep erythrocytes is affected. The role of pituitary hormones on progenitor T-cells was then explored by implanting GH3 cells into Rowett nude rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired disorders affecting the immune system and non-Hodgkin's lymphoma

A case-control study was undertaken to determine whether a prior history of a variety of acquired disorders affecting the immune system was associated with an increased risk of non-Hodgkin's lymphoma. Cases were identified over a 4-year period (1976-1979) at the Johns Hopkins Hospital and individually matched to hospital controls on age, sex, race, and year of diagnosis. For the 109 cases and matched controls who were traced and interviewed, positive associations suggesting an increase in risk were not detected. Instead, there was a suggestion of an inverse relationship. Odds ratios (ORs) were consistently less than 1 for associations between non-Hodgkin's lymphoma and several chronic infectious diseases (OR = 0.65, 95% CI = 0.35, 1.20), chronic inflammatory diseases (OR = 0.88, 95% CI = 0.43, 1.79), autoimmune disorders (OR = 0.80, 95% CI = 0.19, 3.76), and allergic disorders (OR = 0.77, 95% CI = 0.45, 1.32). A statistically significant protective association was found for surgical removal of lymphoid tissue (OR = 0.50, 95% CI = 0.27, 0.91). Adjustment for potentially confounding variables did not change these results. These findings do not support the previously anecdotally reported impression that disorders producing a chronic antigenic stimulus are associated with the development of non-Hodgkin's lymphoma.

Radioiodine therapy of thyroid disease

Ten "ideal" steps used at the University of Michigan to treat well-differentiated thyroid cancer are presented. Using this in 103 patients with well-differentiated thyroid carcinoma and metastases outside their neck, those that were freed of their disease after 131I therapy survived three times as long as those not cured of their disease. Patients successfully cured of their metastases showed better conformity to the "ideal" steps than the patients with residual metastases. Each of the most commonly asked questions about 131I treatment of thyroid carcinoma following surgical treatment are discussed.

Suppressor-cell dysfunction in children with histiocytosis-X

Suppressor-cell activity of peripheral blood mononuclear cells were examined and lymphocyte subsets analyzed in children with histiocytosis-X and in healthy, age-matched subjects. Suppressor-cell function was assessed by two methods, the indomethacin stimulation of mitogen-activated cultures and the concanavalin A-inducible suppressor-cell assay. The results of these two assays indicate that children with active disease have significantly decreased suppressor-cell activity. Additionally, the percentage and absolute number of OKT8+ lymphocytes were decreased in children with active disease. Suppressor-cell activity and lymphocyte subsets returned to normal, baseline levels with disease remission. This study documents for the first time suppressor-cell dysfunction and supports previous investigations in which suppressor T lymphocytes are deficient in children with active disease. These findings may explain certain clinical manifestations seen in children with histiocytosis-X.

Lymphocyte subsets in habitual abortion

Lymphocyte subpopulations were characterized by means of monoclonal antibodies in 25 women with habitual abortion and 21 multiparous normal women. Compared to nonpregnant women (N = 8), pregnant normal women were associated with significantly lower helper-to-suppressor ratios (1.71 +/- 0.41 versus 2.37 +/- 0.66). In contrast in pregnant women with habitual abortion (N = 13) the ratio remained high (2.32 +/- 0.73). Failure to increase the number of suppressors and a significant rise in helpers caused this increased ratio. We discuss the possible mechanisms and etiological importance of this finding in habitual abortion.

T-cell subsets and natural killer cell activity in patients with gestational trophoblastic neoplasia

Lymphocyte counts, T-cell counts, B-cell counts, helper T-cell counts, and suppressor-cytotoxic T-cell counts were performed in 38 patients with gestational trophoblastic neoplasia and 38 normal control subjects. Natural killer cell activity was also assayed in 30 patients and 30 control subjects. The percentage and count of lymphocytes and the absolute counts (but not the percentages) of T cells, helper T cells, and suppressor-cytotoxic T cells in patients with gestational trophoblastic neoplasia were significantly lower than those of normal control subjects. In high-risk patients with gestational trophoblastic neoplasia, there was also a significant reduction of the helper T cell to suppressor-cytotoxic T-cell ratio in comparison with that in normal control subjects. There was no significant difference in the B-cell counts or natural killer cell activity. The measurement of these parameters was not useful in predicting the response to chemotherapy.

L-thyroxine therapy induces a fall of thyroid microsomal and thyroglobulin antibodies in idiopathic myxedema and in hypothyroid, but not in euthyroid Hashimoto's thyroiditis

Thyroid microsomal (MAb) and thyroglobulin (TgAb) antibodies were sequentially measured by sensitive and quantitative radioassays in 17 patients with goitrous Hashimoto's thyroiditis (9 hypothyroid, 8 euthyroid) and in 19 patients with idiopathic myxedema before and at various time intervals up to 24-48 months after the institution of L-thyroxine therapy. Thyroid antibodies were also determined in 5 euthyroid subjects with Hashimoto's thyroiditis maintained without treatment for a similar period. During L-thyroxine administration a reduction of MAb with respect to the pretreatment level was found in 6 of the 9 (67%) hypothyroid patients with Hashimoto's thyroiditis and in 16 of the 19 (84%) patients with idiopathic myxedema. The decrease of MAb was highly significant in both groups (p less than 0.001 and p less than 0.0001, respectively). A fall of TgAb occurred in 2 of the 3 patients (75%) with hypothyroid Hashimoto's thyroiditis and in 9 of the 10 (90%, p less than 0.001) patients with idiopathic myxedema having abnormally elevated pretreatment TgAB levels. No consistent pattern of MAb and TgAb changes was observed in the euthyroid subjects with Hashimoto's thyroiditis, whether treated or untreated. In the hypothyroid patients with Hashimoto's thyroiditis a significant association was found between the decrease of MAb and the reduction of goiter size (p less than 0.05) occurring during L-thyroxine administration. Moreover, the decrease of MAb and TgAb in idiopathic myxedema was greater (p less than 0.05) in the patients with normalized serum TSH (less than or equal to 4 microU/ml) than in those showing only a partial reduction of serum TSH (greater than 4 microU/ml) under L-thyroxine.(ABSTRACT TRUNCATED AT 250 WORDS)

Collagen-induced arthritis and pregnancy in mice: the effects of pregnancy on collagen-induced arthritis and the high incidence of infertility in arthritic female mice

Collagen-induced arthritis (CIA) in mice is a model of inflammatory polyarthritis that has many features similar to human rheumatoid arthritis. In rheumatoid arthritis, pregnancy leads to amelioration of the disease while exacerbation develops after delivery. We used the CIA model to elucidate the role of pregnancy on disease and vice versa. The onset of arthritis in pregnant mice was delayed in the B10.RIII strains immunized with native porcine type II collagen 7-12 days prior to syngeneic [B10.RIII (susceptible to CIA) X B10.RIII] and allogeneic (B10.RIII female X B10.K male that are CIA resistant) pregnancy. In contrast, when mice were immunized on days 1-6 of pregnancy, the onset of arthritis was earlier as compared with controls. In addition, once the mice developed CIA after delivery, the disease showed markedly rapid progression as compared to the control immunized group. Humoral immune responses to type II collagen showed significantly decreased levels on day 14 (at late stage of pregnancy) both in syngeneic and allogeneic postmating immunized pregnant mice. The same effect was also seen in allogeneic premating immunized pregnant mice on day 21 (at mid-stage of pregnancy). The levels of these antibodies increased after delivery. Subclasses of IgG1 and IgG2a antibodies to type II collagen were suppressed during pregnancy. In the pseudopregnant group, these antibodies showed decreased levels on day 14, but did not differ from the control groups on day 21 and 28. Some immunoregulatory changes may play a role in these alterations in pregnant arthritic mice. In comparison to the effects of syngeneic (susceptible X susceptible) pregnancy on CIA, allogeneic (susceptible female X resistant male) pregnancy seemed to be beneficial for the affected individuals. Litter size and mean birth weight were not affected by immunization of type II collagen. After onset of CIA, both syngeneic and allogeneic matings failed to produce offspring in arthritic female mice. The estrus cyclicity was highly disturbed in arthritic female mice and gonadotropin stimulation in arthritic mice induced significantly less ova in oviducts and maturing follicles as compared to nonarthritic controls. Immunological factors yet to be elucidated may be involved in this ovarian dysfunction.

Long-term effect of iodized oil on serum thyroglobulin levels in endemic goitre patients

Serum thyroglobulin (Tg) response to bovine TSH (bTSH) was evaluated in 44 goitrous patients (grades III and IV) living in conditions of chronic iodine (I) deficiency (iodine urinary excretion less than 40 micrograms I/g) and in 26 normal subjects. After the initial clinical evaluation and laboratory tests (bTSH test, T4, T3, anti-Tg and anti-microsomal antibodies) all goitrous patients received 1 ml i.m. of iodized oil (I-oil) and were followed up for 30 months. The bTSH test was repeated at 6, 12, 20 and 30 months after I-oil in 21 subjects. A marked reduction in goitre size was observed in 85% of the patients with a concomitant significant increase in the mean serum T4 and T3 concentrations, a significant fall in the mean serum TSH level and a significant decrease in the T3/T4 ratio. Goitrous patients had elevated serum basal Tg levels (55 +/- 8 SEM micrograms/l) and a significantly mean higher peak Tg value after bTSH (200 +/- 65 micrograms/l) as compared with normal subjects (respectively, 11 +/- 1.4 and 32 +/- 3.4 micrograms/l). Larger goitres (grade IV) had a significantly higher mean peak Tg response as compared with grade III goitres. Treatment with I-oil significantly reduced the mean peak Tg response to bTSH after 6 months (59 +/- 10 micrograms/l) but at 12 and 20 months the peak Tg response after the injection rose, respectively, to 110 +/- 19 micrograms/l and 92 +/- 14 micrograms/l (P less than 0.02 as compared with 6 months), returning to the normal range only at 30 months.(ABSTRACT TRUNCATED AT 250 WORDS)

T cell subsets and thyroid-stimulating antibodies in patients with Graves' disease in clinical remission

Patients with active Graves' disease almost constantly show phenotypic alterations of T lymphocytes, such as an increase of "activated" cells recognized by various surface markers (e.g. la antigens). Such alterations are present in a certain number of apparently cured patients. The data herein reported refer to 25 patients with Graves' disease in clinical remission, in whom we have attempted to correlate T cell subset imbalances, the presence of thyroid-stimulating antibodies (TSAb) and the outcome of the subsequent relapse. The results obtained show a significant association between TSAb and the increase of la-positive T cells: no relationship was found between TSAb and other T lymphocyte subsets. One-year clinical follow-up of the patients enabled us to see relapses of hyperthyroidism in only two patients, who had shown in the first control both TSAb positivity and increased la-positive T cells. These results, in our opinion, suggest a role of la antigens expression on T lymphocytes in the clinical course of Graves' disease.

Autologous mixed lymphocyte reaction (AMLR) in man. XVI. The AMLR and monoclonal antibody-defined T cell subsets and HNK 1+ natural killer cells in normal human pregnancy

Peripheral blood mononuclear cells from 27 pregnant women and 10 age-matched non-pregnant women were examined for monoclonal antibody-defined T cells, immunoregulatory T-cell subsets, natural killer cells, activated T cells and surface Ig+B lymphocytes using a fluorescence-activated cell sorter (FACS analyzer). The autologous mixed lymphocyte reaction (AMLR) and in vitro influence of interleukin 1 (IL-1) and interleukin 2 (IL-2) on the AMLR were also studied. No significant difference was observed in the proportions of Leu 3+ (helper/inducer phenotype) and Leu 2+ (suppressor/cytotoxic) T cells during all three trimesters of pregnancy and in post-partum period when compared to non-pregnant healthy control women. T cells expressing DR antigen (evidence of T-cell activation) were significantly increased during second trimester (P less than 0.02) and in post-partum period (P less than 0.05). However, Tac+ T cells (IL-2 receptor positive T cells, another but distinct marker for T cell activation) were normal throughout pregnancy and in the post-partum period. Leu 7+ (HNK 1+) lymphoid cells (containing a population of natural killer cells) were normal during all 3 trimesters of pregnancy but were increased during post-partum period. Surface Ig+B cells were comparable to control group throughout pregnancy and during post-partum period. The AMLR was significantly deficient (P less than 0.01) during first and third trimester of pregnancy. In vitro addition of purified IL-2 restored the AMLR to the baseline levels of the controls but the AMLR was still lower than the levels in controls with IL-2.(ABSTRACT TRUNCATED AT 250 WORDS)

Thyroglobulin production by malignant thyroid tumors. An immunocytochemical and radioimmunoassay study

Four hundred thirty surgical and biopsy specimens of malignant thyroid tumors of 323 patients were analyzed by histologic and immunocytochemical examination for their thyroglobulin (TG) content. Almost 95% of the differentiated thyroid carcinomas of follicular origin contained immunoreactive TG. The authors could not demonstrate TG in anaplastic carcinomas. Postoperative follow-up and serum TG determinations were available for 111 athyroid patients. Serum TG was elevated in five patients with metastatic or recurrent moderately differentiated follicular carcinoma, in two patients with metastasizing papillary, and in one patient with anaplastic carcinoma. Four patients had detectable serum TG levels without clinical and radiologic evidence of recurrence or metastases. In addition to conventional histologic examination, immunocytochemical demonstration of TG is a reliable and valuable aid in the diagnosis, classification, and determination of the grade of differentiation of malignant thyroid tumors. From this the pathologist can provide a pathologic basis for postoperative patient management.

Thyroiditis

In this review, the major types of immune mediated thyroiditis are described and the etiology explained in the light of current theories of autoimmunity. Hashimoto's thyroiditis is a common autoimmune disease. The onset is gradual with patients presenting with symptoms of hypothyroidism, nonspecific symptoms of the autoimmune process itself, or symptoms relating to a goitre. The disease is usually relentless and, except in young patients, permanent replacement with thyroxine is eventually required. Silent thyroiditis is another autoimmune disease of more acute onset. The initial, thyrotoxic, phase lasting several weeks is due to release of thyroid hormone from damaged follicles, and radionuclidic scans show absent uptake. There often follows a hypothyroid phase with final recovery in most patients. Post partum thyroiditis is due to silent thyroiditis, or, less commonly, Hashimoto's thyroiditis, occurring three to six months after delivery. Subacute thyroiditis often follows a viral infection and is not thought to be an autoimmune disease. It presents with severe thyroid pain and tenderness with marked non-specific symptoms such as myalgia and fatigue. The initial, thyrotoxic, phase is also due to release of thyroid hormone, and radionuclidic scans show absent uptake. A hypothyroid phase often follows and recovery is complete. Hashimoto's thyroiditis appears to be due to a congenitally present, antigen specific, T suppressor lymphocyte defect. It is proposed that in silent thyroiditis there is a less severe Ts defect and a correspondingly greater decompensating factor. In post partum thyroiditis, this factor appears to be a general decline in T suppressor lymphocyte function after delivery. Subacute thyroiditis is not an autoimmune disease. The thyroid appears to be an "innocent bystander" in an immune mediated antiviral attack.

Phenotypic and functional evaluation of suppressor cells in normal pregnancy and in chronic aborters

To evaluate the potential role of immunoregulatory cells modulating the maternal immunologic response during pregnancy, we carried out phenotypic and functional studies in patients with normal obstetrical histories during each trimester and in patients with chronic idiopathic spontaneous abortions. Using monoclonal antibodies (Ortho), total numbers of T cells (T3+) and T4+ cells progressively increased during pregnancy (compared to nonpregnant controls) and then declined in the third trimester. Increased percentages of T8+, T10+, and Ia+ cells were found in the third trimester. The relative decline in numbers of T4+ cells, with increased numbers of T8+ cells, led to a significantly reduced T4/T8 ratio in the third trimester. Histamine receptors on T cells were quantitated by an immunofluorescent technique. Significantly reduced numbers of H1-type receptors were noted during the second trimester of pregnancy and this was associated with a decreased H1/H2 ratio. Functionally, histamine-induced suppression was measured in a lymphocyte proliferation assay. Patients in the first and second trimester of pregnancy had greater histamine-induced suppression of phytohemagglutinin (PHA)-stimulated proliferation at high concentrations of histamine (10(-3) to 10(-7)) but less suppression at the lower concentrations (10(-9) to 10(-11) M), compared to nonpregnant controls. In contrast, patients studied in the third trimester failed to respond to any concentration of histamine. MLC-induced suppressor activity was generated by incubating the maternal cells with either paternal or third-party mononuclear cells for 2 or 6 days and assaying the cell-free supernatant for its suppressive effects on PHA-stimulated proliferation. Maternal responses to paternal cells did not result in significant suppression in 2-day supernatants during any trimester but by 6 days the suppressive activity was equivalent to non-pregnant controls in patients during the first and second trimester. Maternal responses to third party cells was greater during the second trimester than either the first or third trimesters in both 2- and 6-day supernatants. Patients with histories of chronic idiopathic spontaneous abortions, who were not pregnant at the time of study, exhibited normal numbers of T-cell subsets and T4/T8 ratios. Numbers of both H1 and H2 receptor bearing T cells were proportionally reduced, resulting in a normal H1/H2 ratio. Despite having decreased numbers of H1 and H2 receptor bearing cells, histamine-induced suppression of PHA-stimulated proliferation was comparable to nonpregnant controls over the concentration range (10(-3) to 10(-11) M) employed.(ABSTRACT TRUNCATED AT 400 WORDS)

Endocrine regulation of the immune system

Immunoregulation, the major process of self-defence, appears to be more complex than has been previously thought, involving the central nervous and endocrine systems. This review demonstrates growing evidence for the hypothesis that endocrine factors from the pituitary and hypothalamus directly influence the development and function of the immune system. Both pituitary and hypothalamic hormones interfere with lymphocyte proliferation and function. Proliferation of T-lymphocytes as well as production of immunoglobulins by plasma cells seem to be hormone dependent. Clinical observations suggest that hematological, oncological, and immunological disorders known for their immune pathogenesis are associated with alterations of the endocrine homeostasis. Recently, human peripheral mononuclear cells have been shown to possess specific receptors for pituitary hormones. It is hypothesized that proteohormones act directly on lymphocytes via specific membrane receptors. Thus, the endocrine system, closely related to cortical and subcortical centers in the central nervous system, is one of the body's instruments to regulate and modulate its immune response. This hypothesized immunoregulatory pathway via the central nervous system and endocrine glands may well be of importance for the body's defence against infectious and malignant diseases. In addition, a new picture of the complex immunoregulatory mechanisms emerges for a better understanding of the function of the immune system. However, there is no single hormone which has yet been identified as being crucial for development and/or function of the immune system. It appears from the literature that a number of various proteohormones rather than a single hormone acts on immunocompetent cells.

Graves' disease with neutropenia and marked splenomegaly: autoimmune neutropenia due to propylthiouracil

A 38-year-old man with Graves' disease taking propylthiouracil (PTU) for 6 years developed neutropenia and marked splenomegaly. After subtotal thyroidectomy with discontinuance of PTU the patient remained asymptomatic for the last two and half years. The serum obtained during the period of neutropenia demonstrated opsonic activity to neutrophils of the patient as well as of normal volunteers. This opsonic antineutrophil activity was located in the IgG fraction of the serum. Furthermore, PTU at the concentration (0.1-1.0 micrograms/ml) attainable in the patient's serum significantly stimulated [3H] thymidine incorporation in the patient's lymphocytes. These findings indicate that the patient developed autoimmune neutropenia by producing opsonic antineutrophil antibodies in association with the PTU therapy.

A high prevalence of thyroglobulin autoantibodies in adults with and without thyroid disease as measured with a sensitive solid-phase immunosorbent radioassay

Sera from 228 patients with thyroid disease and 140 healthy subjects without clinical or biochemical evidence of thyroid disease, were tested using a sensitive solid-phase immunosorbent radioassay (RIA) and a passive hemagglutination test (TRC test) for thyroglobulin antibodies (Tg-ab). With the RIA technique, Tg-ab was found in 27% of the controls (36% of the women and 15% of the men), whereas only 0.7% of them were Tg-ab positive with the TRC test. All individuals with primary hypothyroidism were Tg-ab positive with the RIA, compared with only 56% with the TRC test. Tg-ab (RIA) were found in 43/53 (81%) of the patients with toxic diffuse goiter, and in 30-40% of the patients with toxic nodular goiter, toxic adenoma, atoxic goiter, and thyroid carcinoma, the TRC test being positive in 10-17% of these patients. The high prevalence of Tg-ab in the healthy population suggests that subclinical thyroiditis is more frequent than has been assumed from antibody measurements made with less sensitive methods, and is in agreement with the prevalences reported from autopsy studies.

Diagnostic value of a single serum thyroglobulin determination on and off thyroid suppressive therapy in the follow-up of patients with differentiated thyroid cancer

To assess the significance of a single serum thyroglobulin (Tg) determination on and off thyroid suppressive therapy, serum Tg measurements have been performed in 349 serum samples from 82 patients with differentiated thyroid cancer. All samples were collected after total thyroidectomy with or without subsequent ablation of residual thyroid tissue by radioiodine. One hundred and fifty-three samples were obtained while the patients were on thyroid suppressive therapy and 196 after withdrawal of medication. The results of serum Tg assays were analysed in relation to the presence or absence of residual or metastatic thyroid tissue, as assessed by clinical and laboratory evaluation, including 131I whole body scan. In patients with thyroid residue but no metastases, undetectable serum Tg (false negative results) occurred in 45% of cases off therapy and in 92.9% of cases during therapy. In the presence of metastases no undetectable serum Tg result was found in patients off therapy, while four (6.9%) out of 58 samples from patients with bone and/or lung metastases and seven (31.8%) out of 22 samples from patients with lymph node metastases alone were undetectable (falsely negative) during suppressive therapy. Serum Tg was undetectable in sera from patients with no evidence of thyroid residue or metastatic disease in all but one (1.7%) of 59 samples on and three (5.4%) of 56 samples off suppressive therapy. These Tg results were confirmed to be truly rather than falsely positive, since evidence of metastatic disease was obtained by whole body scan after the administration of therapeutic doses of 131I.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoimmunity and pregnancy

The general effect of pregnancy on autoimmunity remains controversial. In the majority of cases, pregnancy may have no effect on the disease, while on other occasions, pregnancy induces exacerbations that may be especially pronounced in the immediate post-partum period. The reasons for this preponderance are still unclear. Another important aspect of autoimmune diseases during pregnancy entails the passive transfer of the disease into the fetal compartment. It seems that until the pathogenesis and a better specific therapy for autoimmune diseases are clearly defined, careful clinical and immunologic observation of each mother-infant pair will be invaluable.

Pseudotumor cerebri and thyroid-replacement therapy in patients affected by differentiated thyroid carcinoma

The pseudotumor cerebri, a neurological syndrome clinically characterized by headaches, vomiting and bilateral papilledema, occurred in two patients, previously subjected to total thyroidectomy for differentiated thyroid carcinoma, after initiation of levothyroxine replacement therapy. In patients with thyroid cancer, subjected to thyroidectomy and then thyroid hormone replacement therapy, the possible development of pseudotumor cerebri syndrome should be considered and differentiated from CNS symptoms due to brain metastases.

Reciprocal changes of serum thyroglobulin and TSH in residents of a moderate endemic goitre area

Subjects living in iodine deficient areas were reported to have elevated serum thyroglobulin (Tg) concentrations. This finding was interpreted as related to thyroid stimulation. Discrepant results, however, were found when serum Tg concentrations were correlated either with serum TSH or with goitre size. In this study we investigated the relationships between goitre size, serum Tg and serum TSH in 488 unselected adult subjects living in an endemic area of North-Western Tuscany (Garfagnana district). The control group comprised 352 subjects residing in a non-endemic area. In the endemic area a high prevalence of goitre was found (80.1%), thyroid enlargement being slight to moderate in the majority of cases and very large only in six subjects. Serum Tg concentrations increased and serum TSH levels decreased with the size of goitre. Statistical analysis by the chi-square cross correlation test showed that the converse changes of serum Tg and serum TSH in relation to goitre size were highly significant. These findings indicate that the increase of serum Tg occurring in endemic goitrous subjects may be related to factors other than TSH stimulation. Functional autonomy of the thyroid may account for the finding of low serum TSH and elevated serum Tg values in patients with large goitres. The present data do not exclude the possibility that the release of Tg is influenced by TSH stimulation, but indicate that other factors may be responsible for the increased levels of Tg found in endemic goitre.

Polyglandular autoimmune syndromes

Dysfunction of multiple endocrine glands may develop as the result of hypopituitarism, various infiltrative disorders, or an organ-specific autoimmune mechanism. When dysfunction of two or more endocrine glands occurs in association with circulating organ-specific antibodies directed against the involved glands, the term polyglandular autoimmune syndrome is applied. Characteristics of polyglandular autoimmunity include specific patterns of disease association and frequently a family history of similar involvement. The principal endocrine components of these syndromes are adrenal insufficiency, autoimmune thyroid disease, insulin-dependent diabetes mellitus, and premature gonadal failure. In addition, primary hypoparathyroidism is a key feature of one form of polyglandular autoimmunity that occurs in children. Several nonendocrine organ-specific autoimmune disorders are also associated with polyglandular autoimmunity, of which pernicious anemia is the most frequent. The underlying abnormality responsible for polyglandular autoimmunity is most likely a defect in T suppressor cell function, but there is evidence that aberrant expression of HLA DR antigens also plays an important role in the pathogenesis of these disorders.

Proliferation of T8-positive cytolytic T lymphocytes in response to thyroglobulin in human autoimmune thyroiditis: analysis of cell interactions and culture requirements

These experiments were designed to analyze the involvement of T-lymphocyte subpopulations in autoimmune thyroid disorders such as Graves' Disease (GD) and Hashimoto's Disease (HD). In a first set of experiments, lymphocytes isolated from thyroid infiltrates or from peripheral blood of GD and HD patients were analyzed for the expression of various surface antigens. While HLA-DR + T cells were numerous among thyroid infiltrating T lymphocytes in both groups of patients, the proportions of T8 + cells (as defined by their reactivity with the B 9.4 monoclonal antibody specific for T8 surface molecule) were strikingly different in HD and GD. In the latter group of patients only 19% of infiltrating T cells were T8 +, whereas these cells represented approximately 50% in four HD patients. Given the previous demonstration that all T cells expressing T8 antigen are cytolytic T lymphocytes (CTL) or their precursors (CTL-P) in conjunction with the fact that lymphocytes from HD or GD patients are known to proliferate in vitro in response to human tg (Htg), we further analyzed the T-cell subset(s) responsible for in vitro proliferation to Htg. In these experiments, peripheral blood T lymphocytes purified from patients with GD or HD were cultured with 1 microgram/ml Htg and irradiated autologous T-depleted mononuclear cells as the source of antigen presenting cells (APC). The proportions of T8 + cells declined considerably during culture in GD patients, but at Days 6 to 9, T8 + cells represented as much as 51% of cultured T lymphocytes from patients with HD. Moreover, the majority of T8 + cells were medium-large size lymphoblasts. Removal of Htg at Day 6 resulted in both abrogation of proliferative responsiveness and in decreases of T8 + percentages. Further analysis of the cell interactions leading to T8 + cell proliferation in response to Htg showed that helper/inducer T cells, as defined by 5/9 antigen expression, were strictly required. Collectively, these features are reminiscent of the T-cell involvement in experimental autoimmune thyroiditis of mice and stress for the first time the potential role of CTL in tissue damage occurring in Hashimoto's thyroiditis.

The pathogenesis of Graves' ophthalmopathy

The pathology of the orbital changes in Graves' ophthalmopathy (GO) has been discussed in detail. The target tissue is the eye muscle and the damage probably results from autoimmune processes. Cell-mediated immune responses have been demonstrated and an antibody to eye muscle is detectable in 70% of patients. There is no direct evidence for an effect of thyroid hormones or TSH on orbital tissues in GO. The relation between GO and autoimmune thyroid disease is discussed. Present evidence suggests that in GO autoimmune responses are directed to orbital tissue antigens and do not cross-react with thyroid antigens. Clinical studies suggest that all patients with hyperthyroidism have some abnormality of eye muscle, whereas not all patients with ophthalmopathy have evidence of thyroid disease. It is not possible at the present time to be certain whether GO is an integral part of Graves' disease or a separate entity.

Post-partum hyperthyroidism

The importance of recognizing the frequent occurrence of the destructive (i.e. PPT) and stimulatory (i.e. PGD) causes of PH have been discussed. The estimated prevalence of PH in several geographical regions of Japan, North America and Europe ranges from 2.0-5%. Although the autoimmune basis for GD has been well-established, the clinical and laboratory features of PPT as well as the alterations of humoral and cellular thyroidal immune parameters, the typical needle biopsy evidence of lymphocytic infiltration, and the association with HLA and Gm allotypes associated with the PPT syndrome, favour the view that it is also likely a variant form of subclinical ATD which becomes transiently more active post-partum. Post-partum transient hyperthyroidism with or without transient or permanent hypothyroidism and relapse of GD thyrotoxicosis have been observed in patients with or without a previous history of GD. Hence, an RAIU test is the preferred diagnostic test in differentiating between these two entities, especially in the absence of associated stigmata of GD. When the RAIU test is suppressed, other causes such as thyrotoxicosis factitia and iodine exposure should be excluded. Without an RAIU test, only a rapid and spontaneous resolution of post-partum hyperthyroidism, accompanied by laboratory confirmation of a subsequent hypothyroid phase, can indirectly facilitate the differentiation between PGD and PPT. In the first trimester of pregnancy, an increased FT4I has been proposed as a risk factor for PGD and an increased AMA titre for PPT. Depending upon clinical manifestations, severity, patient and physician preferences, PGD can be treated by one of several choices of conventional therapy. The transient thyrotoxic phase of PPT when relatively asymptomatic may require no therapy, but when symptomatic, only conservative therapy with beta-adrenergic blockers, sedatives and/or tranquilizers is indicated. Close follow-up and long-term surveillance of mothers with PH due to PPT is essential for early detection and management of a possible subsequent hypothyroid phase, which may be symptomatic, but is seldom permanent. Treatment of recurrent episodes of PPT is controversial. Thyrotoxic symptoms are usually mild and transient and can best be managed by symptomatic therapy as indicated. In a few exceptional patients with recurrent episodes, prophylactic treatment with corticosteroid may be warranted but thyroidectomy and ablative radioactive iodine therapy is seldom justified.(ABSTRACT TRUNCATED AT 400 WORDS)

Correlation of thyroglobulin measurements and radioiodine scans in the follow-up of patients with differentiated thyroid cancer

Correlation of radioiodine (131I) scans and serum thyroglobulin (Tg) concentrations were performed in the follow-up of 85 differentiated thyroid cancer patients who had undergone total thyroidectomy. Tg results were also compared with the control group of 33 thyroidectomized patients with no evidence of thyroid carcinoma and normal values for Tg established. Excellent correlation between Tg and scans was noted in patients with scan evidence of metastasis distant from the neck. Poor correlation was present in patients with scan evidence of local neck metastasis only, thyroid bed activity, and those with mediastinal activity. In addition, in 8% of the patients, the Tg assay could not be performed because of interfering antibodies. The conclusion is that elevated Tg concentration is a good indicator of metastasis outside of the neck as detected by 131I scans. Caution should be used when Tg alone is used in evaluating local neck metastasis demonstrated on scans. The significance of mediastinal activity warrants further investigation.

[Diagnostic procedure in suspected functional disorders of the thyroid gland]

In an attempt to derive diagnostic concepts for thyroid diseases we present pathophysiological models for the prevalent thyroid disorders. 'Euthyroid goiter' is a disease mainly caused by iodine deficiency but an additional immunopathogenesis was recently proposed. The 'immunthyropathy' is the thyroid disease with orbitopathy and other extraglandular immunological manifestations. A complete model of the immunological phenomena which begin with a tolerance defect is given, and both the T-cell, and B-cell-mediated pathways are detailed. The complex interaction of immunoglobulins at the thyroid-stimulating hormone receptor and their dependency on human leukocyte antigen loci are presented. The peripheral metabolism depends ultimately upon a prevalence of thyroid gland stimulation (thyrotoxicosis) or glandular destruction (hypothyroidism) and this is true for overt thyroid disease under antithyroid drug therapy or any other therapy. Euthyroidism during 'immunethyropathy' is presented as an equilibrium between thyroid stimulation and destruction. This concept allows an exact description of the thyroid disease and the resulting clinical situation provided that established laboratory tests are used as suggested by the model. 'Disseminated thyroid autonomy and autononous thyroid adenoma' develops during goitrous thyroid disease as a consequence of uncoupling of thyroid cellular growth stimulation, iodine utilization, and thyroid hormone synthesis. The polyclonal origin seems more frequent than monoclonal foci. The size of autononous tissue and individual iodine supply determines the endocrine function in this disease. The TRH test monitors with great sensitivity subtle increases in T4 or T3 production and indicates critical clinical situations earlier than the scintiscan.(ABSTRACT TRUNCATED AT 250 WORDS)

T-cell sensitization to autologous thyroid cells and normal non-specific suppressor T-cell function in Graves' disease

We have employed a syngeneic system utilizing thyroid cell monolayers initiated following thyroid surgery co-cultured with autologous T cells to demonstrate T cell autosensitization in patients with Graves' disease. Antigen-induced blastogenesis was monitored using 24 h [3H]thymidine uptake. Control experiments with 5 d cultured normal human thyroid cells from tissue around benign adenomata showed no evidence of syngeneic T cell autosensitization. Human thyroid cells alone were unable to incorporate [3H]thymidine in the presence of bTSH. In three of four experiments with Graves' thyroid cells there was significant induction of autologous T cell blastogenesis with a mean stimulation index of 220%. In parallel experiments we explored the non-specific helper and suppressor T cell function of these and similar patients with Graves' disease. In normal controls (n = 6) increasing numbers of T cells added to a constant number of B cells (consisting of a T cell depleted peripheral mononuclear cell preparation) showed a marked helper effect measured as increasing IgG secretion. As the ratio of T:B cells increased above 4:1 there was a suppression of IgG secretion. One of two hyperthyroid Graves' patients was observed to have deficient T cell function as demonstrated by lack of IgG suppression. The remaining five patients (all but one of whom were euthyroid at the time of testing) had results similar to the controls indicating normal suppressor T cell function in this disease. Such data showed that patients with Graves' disease possessed circulating T cells which exhibited autosensitization to syngeneic thyroid cell surface antigens, a phenomenon not demonstrable in control individuals. Furthermore, this specific T cell autosensitization did not interfere with non-specific T cell function as judged by its influence on IgG secretion.

T cell and T cell subset determination in normal peripheral blood: comparison of the indirect immunofluorescence and lymphocytotoxicity techniques

We compared a simple complement-dependent lymphocytotoxicity test with a widely used indirect immunofluorescence procedure to enumerate total T, T helper, and T suppressor lymphocytes in normal blood samples. Results with the two techniques were closely similar.

Autoimmune thyroid disease: purification and phenotypic analysis of intrathyroid T cells

A phenotypic analysis of T cells infiltrating the thyroid of patients with autoimmune thyroid disease (both Graves' disease and Hashimoto's thyroiditis) was performed. T lymphocytes were purified from mononuclear cells extracted from surgically removed tissue. The following markers were evaluated: la antigens, MLR4 antigen (expressed on activated T cells) 5/9 antigen (expressed on a subset of lymphocytes containing the whole "helper-inducer" activity in vitro), Fc gamma-receptors, B9 antigen (expressed by cytotoxic, or precursor of cytotoxic, T cells). We observed increased percentages of 5/9-, MLR4- and la-positive T cells with respect to peripheral blood in both HT and GD: on the contrary, in specimens from nonautoimmune thyroid diseases mononuclear infiltrate was minimal, and even T cell evaluation was not possible. In addition, B9- and Fc gamma-positive T cells were increased in Hashimoto's, but not in Graves' thyroid tissue, thus suggesting a different role of cytotoxic effector mechanisms in the two diseases.

Enzyme-linked immunosorbent assay for determination of thyroglobulin autoantibodies. Comparison with RIA and haemagglutination

An enzyme immunoassay (ELISA) has been developed for the detection of human autoantibodies to thyroglobulin (TgAb). The ELISA assay was compared to the previous routine method, the tanned red cell (TRC) method and a radioimmunoassay (RIA) technique for thyroglobulin autoantibodies. Sera from 163 healthy non-hospitalized persons, 31 patients with Hashimoto's thyroiditis, 13 patients with Graves disease, 136 patients with thyroid cancer and 365 sera consecutively received for thyroid autoantibody screening were examined for TgAb in the three methods. The nosological sensitivity for ELISA methods was comparable to that of RIA and higher than that of TRC. The ELISA method was accurate, precise, objective, inexpensive and well suited for quantitative routine determination of TgAb.

Antithyroid drugs

Over the past four decades, a great deal has been learned about the pharmacology and mechanisms of action of antithyroid drugs. Their ability to inhibit hormone biosynthesis involves complex interactions with thyroid peroxidase and thyroglobulin, many of which are still poorly understood. Their spectrum of activity is much wider than previously thought, and a number of clinically important extrathyroidal actions have been identified. Despite a greater appreciation for the intricacies of antithyroid-drug pharmacology, controversies still surround the use of these agents in the treatment of thyrotoxicosis. These controversies are apt to continue until the pathophysiology of Graves' disease is fully elucidated.

A mature thymocyte-like phenotypic pattern on human cord circulating T-lymphoid cells

Cord blood samples from healthy full-term newborns were tested with antimature and antiimmature lymphoid-cell monoclonal antibodies, as well as more traditional markers, in order to identify the phenotype of circulating precursor cells. The results demonstrated that human cord blood contains a lower number of OKT3+, E-rosetting mature T cells than adult blood, very high levels of OKT10+ cells, and few OKT9+, OKT8+ OKT3-, and OKT4+ OKT3- cells. Although the finding of OKT9+ and OKT10+ cord circulating cells could be indicative of cell activation, double marker studies in newborn blood pointed to phenotypically immature lymphoid subsets at different stages of maturation, according to Reinherz's hypothesis. In addition, the absence of nuclear Tdt-positive and hot-rosetting cells, together with the fact that most of these are OKT3+, OKT10+, OKT4+, or OKT8+ cells, suggests that the surface phenotype of newborn lymphocytes is similar to that of mature thymocytes.

Metastatic medullary and undifferentiated thyroid cancers are not associated with elevated levels of serum thyroglobulin

It is now well accepted that serum thyroglobulin (Tg) determination is a specific marker of disease activity in well-differentiated thyroid cancer after total thyroidectomy. In this study we examined 15 thyroidectomized patients with metastases from medullary thyroid cancer and 10 patients with metastases from undifferentiated thyroid cancer, to determine whether serum Tg measurement could be useful also in these types of thyroid tumors. In contrast with differentiated thyroid cancer, which had high levels of circulating serum Tg, patients with medullary and undifferentiated thyroid cancer had undetectable or low levels of serum Tg. Thus, serum Tg measurements are not useful in the diagnosis of metastatic disease in these patients.

Serum thyroglobulin in patients with autonomous thyroid nodules

To investigate further the relationship between thyroid hormones and thyroglobulin (TG) secretion, total and free thyroid hormone levels, TSH and its response to TRH and serum TG concentrations were determined in 61 patients with solitary autonomous thyroid nodules. Thyroid function varied widely from euthyroidism to clearcut thyrotoxicosis. Serum TG levels were significantly higher in patients than in normal controls. Individually they were above the normal range (greater than 50 ng/ml) in 95% of the patients, as well as in those with normal total and/or free thyroid hormone levels. Patients with high total and/or free thyroid hormone levels had higher TG concentrations than euthyroid patients. TG concentrations were significantly correlated with FT3 values. They were higher in patients in whom TSH was unresponsive to TRH than in the responsive groups. TG was also slightly higher in patients with hot nodules than in those with warm nodules. These data seem to indicate that TG is secreted along with thyroid hormones in the absence of any stimulatory action. It also is a sensitive index of thyroid hyperfunction. Twenty patients were controlled 6 months after nodulectomy. TG levels, though significantly lower than in the preoperative state, were still higher than in normal subjects. This increase was attributed to persistent hyperthyroidism in two patients only. The observation that the increase in TSH after TRH stimulation in post-operative patients was greater than that found in normal controls led us to believe that in most cases the high TG levels after surgery are due to stimulation of the normal thyroid tissue by rebound TSH secretion.

Serum thyroglobulin in newborns' cord blood, in childhood and adolescence: a physiological indicator of thyroidal status

Serum thyroglobulin (Tg) was measured in the cord blood of 635 newborns and serum thyroxine (T4) reverse triiodothyronine (rT3), TSH and T3 were measured in about 200 of them. Cord Tg was detectable in all newborns with a mean +/- SE value (50 +/- 1.3 ng/ml) higher than that found in the serum of adult subjects (n = 144; Tg = 13 +/- 1.1; p less than 0.0001). Cord Tg had a log-normal distribution. A low, but positive correlation was found between cord Tg and cord TSH (n = 242; r = 0.17; p less than 0.05) but not with cord T4 or cord rT3. Gestational age was negatively correlated with cord Tg or cord rT3 (rS = 0.97; p less than 0.01; rS = -0.89; p less than 0.02, respectively) while was positively correlated with cord T4 or cord TSH (rS = 0.85; p less than 0.05; rS = 0.86; p less than 0.01, respectively). Birth weight, maternal diabetes, induction of labor with oxitocin, cesarian section and newborns' illness showed no influence on cord Tg levels when considered alone, but decreased cord Tg levels were found in ill newborns delivered by cesarian section. On the contrary, increased cord Tg levels were present in cord blood of newborns who developed hypoglycemia soon after birth and in small for gestational age newborns. In 24 newborns studied daily for the first 6 days of life, serum Tg was always detectable with mean values not different from those found in the cord blood.(ABSTRACT TRUNCATED AT 250 WORDS)

A new sensitive immunosorbent radioassay for the detection of circulating antibodies to polypeptide hormones and proteins

A solid-phase immunosorbent radioassay for the detection of circulating antibodies to protein hormones is described. The assay is based on the binding of the homologous 125I-labelled antigen to the antibodies which are then bound to anti-IgG antibodies covalently coupled to Sepharose. It can easily be applied as a complement to any radioimmunoassay for the detection of circulating antibodies to the ligand measured. The assay system avoids falsely elevated values due to interference of high serum concentrations of the antigen. The assay was applied to measure antibodies to FSH, LH, TSH, GH, prolactin, insulin and thyroglobulin (Tg). Among patients with chronic thyroiditis Tg antibodies were found in 100% of the sera. In diffuse toxic goitre 73% of the patients had detectable Tg antibodies. Insulin antibodies were present in 82% of the sera from patients with insulin treated diabetes. No antibodies were found against the other protein hormones tested.

Analysis of lymphocyte subsets in patients with aplastic anaemia

Lymphocyte subsets have been measured in the blood of 28 patients with aplastic anaemia. The mean helper/inducer:suppressor/cytotoxic T lymphocyte ratio (1.24 +/- 0.74) was significantly decreased in the total population in comparison to mean ratios in a normal population (1.78 +/- 0.57) and in patients with other haematological diseases (1.82 +/- 0.92). A reversed ratio (less than or equal to 1) was present in a large proportion (53%) of aplastic patients, due both to an absolute deficiency of helper/inducer lymphocytes and an increase in suppressor/cytotoxic lymphocytes. Increased HLA-DR expression, evidence of lymphocyte activation, was present in seven of 12 patients evaluated and was confined to the suppressor/cytotoxic lymphocyte population. In the bone marrow, the percentage of lymphocytes was increased two-fold compared to normal bone marrow but the ratio of T cell subsets was not abnormal. Two of four patients evaluated after haematopoietic recovery following ATG treatment showed a return to normal of the T4/T8 ratio; in two others a low T4/T8 ratio persisted despite recovery. These results indicate that lymphocyte subset imbalance and lymphocyte activation are present in many patients with aplastic anaemia, either as a contributing factor or as a result of bone marrow failure.