Lymphocyte subpopulations in normal and preeclampsia pregnancies

We have made an effort to determine whether or not there is any change in subpopulations of lymphocytes in normally pregnant and preeclamptic pregnancies using monoclonal antibody markers. Eleven normally pregnant and ten women with preeclampsia were studied, both during the third trimester and again two months postpartum, and compared to eleven age-matched nonpregnant women. Mononuclear cells were isolated from heparinized venous blood. One million cells were treated with each appropriate antibody (Ortho-mune OKM1, OKT3, OKT4, OKT8, OKT11, OKIa), and then reacted with FITC-antimouse IgG and examined by flow cytometry and/or fluorescence microscopy. No significant differences between these three groups were noted in the OKT3, OKT4, OKT8, OKT11, or OKIa cellular populations. The OKM1 population was significantly decreased in the third trimester of normal pregnancies but not in the preeclamptic pregnancies. No significant differences were found 2 months postpartum.

The relationship of maternal antibody levels to post-cesarean section endometritis

One hundred eight pneumococcal polysaccharide antibody levels were determined by radioimmunoassay preoperatively in 18 patients who underwent elective repeat cesarean section. Eight patients developed post-cesarean section endometritis, and 10 did not. The endometritis group did not vary significantly from the noninfected group in preoperative hematocrit, social status, number of previous pregnancies, maternal and newborn weights, length of operation, and Apgar scores. Mean antibody levels in the endometritis group were significantly lower than those in the control group (49 versus 103 ng/ml; p less than 0.05). Mean antibody levels for the six serotypes in the endometritis group were significantly lower than those in the control group (p less than 0.05). This study indicated that a healthy maternal immune system may play an important role in preventing post-cesarean section morbidity. Pneumococcal polysaccharide antibody levels may be used in pregnancy to assess the risk for post-cesarean section infections.

Transfusion-associated cytomegalovirus infection and acquired immune deficiency syndrome in an infant

An infant who received multiple blood transfusions in the neonatal intensive care unit developed a transfusion-associated CMV infection at age 11 weeks and thereafter was noted to have hepatosplenomegaly, mitogen hyporesponsiveness, persistent viruria, an abnormal distribution of T-lymphocyte subpopulations, and poor growth. He has had recurrent opportunistic infections, including Pneumocystis carinii pneumonia. Six donors of blood products received by this infant were investigated; one was found to have chronic lymphadenopathy, weight loss, intermittent diarrhea, lymphopenia, and a profound depression of lymphocytes with a helper/inducer surface phenotype (T4 positive). Family members have an abnormal distribution of T cell subpopulations similar to those reported in asymptomatic homosexuals. The course of disease in our patient suggests that acquired immune deficiency syndrome may be transmitted to young infants via blood products.

Should one measure serum thyroglobulin in the presence of anti-thyroglobulin antibodies?

Thyroglobulin auto-antibodies (anti-Tg) may affect measurement of serum thyroglobulin (Tg). We have assayed sera for Tg by RIA regardless of presence or absence of anti-Tg, and this study was designed to assess the influence of anti-Tg on the results. Binding of human anti-Tg by the second antibody in our RIA (sheep anti-rabbit immunoglobulin) is very low and sera containing anti-Tg of varying titres do not systematically affect assay of Tg regardless of concentration. In our follow-up study of patients with thyroid cancer, correlation between clinical state and Tg concentration is greater than 97% whether anti-Tg is present or absent. These results indicate that in our assay anti-Tg positive sera do not need to be excluded.

Depression of the lymphocyte transformation response to microbial antigens and to phytohemagglutinin during pregnancy

Lymphocyte transformation (LT) responses to Chlamydia trachomatis, to four other microbial antigens, and to phytohemagglutinin (PHA) were studied in 201 women during pregnancy and/or 3-18 wk postpartum. The LT responses to all stimulants tested were significantly depressed during pregnancy when compared with postpartum LT responses. This difference occurred whether LT assays were performed in autologous or pooled heterologous plasma collected from nonpregnant donors. Among women studied in the third trimester and again postpartum, the autologous LT stimulation index (LTSI) rose from 1.7 to 3.4 (P less than 0.001) with C. trachomatis elementary body antigen, from 3.7 to 7.9 (P less than 0.001) with Candida albicans cell wall extract, from 4.5 to 7.8 (P = 0.008) with streptokinase-streptodornase, from 1.7 to 3.0 (P = 0.007) with fluid tetanus toxoid, from 1.7 to 2.8 (P = 0.046) with mumps virus skin test antigen, from 35.5 to 87.0 (P less than 0.001) with PHA (2 micrograms/ml), and from 107.2 to 181.9 (P = 0.007) with PHA (10 micrograms/ml). LT responses to C. trachomatis were compared in 52 pregnant women and 58 nonpregnant women; all the women had C. trachomatis isolated at the time of LT assay. Using either plasma supplement, the mean LTSI with C. trachomatis antigen was significantly higher in nonpregnant women than in pregnant women, regardless of trimester (P less than 0.001). Among 12 women who were serially tested and remained culture positive for C. trachomatis throughout pregnancy and the postpartum period, the mean autologous LTSI rose from 1.9 in the third trimester to 7.8 postpartum (P = 0.0004). These data are the first to show that the immune response to an ongoing bacterial infection is depressed during pregnancy and to definitively document the depressed LT responses during human pregnancy.

T-cell subsets in patients with preeclampsia

Peripheral blood mononuclear cells from patients with preeclampsia were enumerated by means of monoclonal anti-T-cell antibodies. The percentage of total T cells was significantly decreased in this group of patients, as compared with normal term pregnant women. The low proportion of T cells was due to a proportional reduction in both helper and suppressor T cells; therefore, the ratio of helper to suppressor T cells was not different from that in normal pregnant women. There was no correlation between the degree of reduction in percentage of T cells and severity of the disease. The absolute numbers of T cells were slightly, but not significantly, decreased. Our findings support previous evidence of reduced, not increased, immune reactivity in preeclampsia.

Circulating antitriiodothyronine autoantibodies in two euthyroid patients: apparent lack of interference in total T3 radioimmunoassay based on second antibody or solid phase separation techniques

Two clinically euthyroid patients were noted to have low total T3 levels as assessed by RIA using either dextran-charcoal (DC) or polyethylene glycol (PEG) for separation of bound from unbound T3, in spite of normal free T3, total and free T4 and basal and TRH-stimulated TSH concentrations. The presence of circulating substances binding T3 was suggested by high nonspecific binding in total T3 RIA system using either DC or PEG separation. The presence of anti-T3 autoantibodies was then suspected and confirmed by the presence of [125]-T3 bound to patients' gammaglobulins, precipitated with rabbit anti-human immunoglobulins. Serum T3 concentration determined by extracting T3 from patients' sera with methanol was 166 and 226 ng/dl. Similar or even lower values were unexpectedly obtained in RIA systems with solid phase or second antibody (anti-rabbit) separation and with competitive protein binding assay. To face this paradoxical finding, simulated experiments were carried out by incubating T3- and T4-free sera added with various amounts of stable T3 and T4 in the presence of goat anti-T3 or anti-T4 serum. These samples were then radioimmunoassayed. The DC separation caused a consistent underestimation of the actual T3 and T4 concentration. The second antibody separation caused a T3 and T4 overestimation for actual levels below 200 ng/dl and 10 micrograms/dl, respectively, while at the higher T3 or T4 concentrations, an overlap or, even, an underestimation of actual T3 or T4 levels were found. These data provide evidence that, with second antibody or solid phase separation methods, there could be an apparent lack of interfering effect of endogenously occurring antibodies.

Steroids as immunosuppressants in pregnancy

In considering the potential of known reproductive hormones to act as immunoregulatory substances during pregnancy, progesterone clearly is an attractive candidate for the following reasons: 1) progesterone is a primitive hormone occurring in virtually all species; 2) it is the only hormone which has been shown to be absolutely essential for maintenance of pregnancy in a variety of mammals, including the human; 3) it has demonstrable in vivo and in vitro immunosuppressive effects when present in concentrations known to be present in the human placenta; 4) it has weak systemic effects compared to cortisol; 5) in many species including primates, it is produced by trophoblastic cells: potential targets of the maternal immune system. Inhibitory effects of progesterone on immune cells have been demonstrated despite the absence of classical steroid receptors for progesterone (Lippman 1979). Specific functions of human T-lymphocytes and macrophages are inhibited by concentrations of progesterone known to occur in the placenta (10(-6)-10(-5) M). Although similar effects are produced by cortisol, clear-cut differences exist in the mechanisms by which cortisol and progesterone act on immune cells. The results suggest, but do not prove, that progesterone does not act on immune cells by binding to the glucocorticoid receptor. This can be considered to be advantageous, for otherwise pregnancy could be associated with glucocorticoid toxicity. Remarkable local anti-inflammatory activity of progesterone has been observed in vivo, although the mechanism of this effect is poorly understood. The striking absence of inflammatory cells in the pregnant uterus until a few days before birth is consistent with known effects of progesterone from animal studies. Whether this regulatory effect on cell traffic is exerted directly by progesterone or by secondary mediators produced within the uterus remains to be determined. In either case, appropriate timing of the removal of progesterone's influence may constitute an integral part of the process of parturition. Post-partum resolution of the placental attachment-site has many of the cellular characteristics of transplant rejection. Furthermore, it has recently been proposed that inflammatory cells which invade the cervix may generate prostaglandins which mediate the biochemical changes that are essential for its dilation to allow escape of the fetus (Liggins 1981). If the processes begin prior to delivery as a consequence either of progesterone withdrawal or inhibition of its activity, parturition may in fact be considered as a delayed rejection process.(ABSTRACT TRUNCATED AT 400 WORDS)

Mononuclear cell subpopulations during normal pregnancy: I. Analysis of cell surface markers using conventional techniques and monoclonal antibodies

Previous reports indicate depression of cellular immunity during pregnancy. In order to get a deeper insight into the immunoregulatory subsets of mononuclear cells in pregnant women, we analyzed the percentages of T and B lymphocytes, T cell subsets and cells expressing IgG-Fc and C3 receptors, and M1- and Ia-like antigens in venous blood samples from healthy women and pregnant women at different gestational ages and after delivery. Even if a trend toward a progressive decrease of T lymphocytes and T4+ helper subset was observed throughout pregnancy, along with a slight increase in the percentages of cells bearing C3 receptors, M1, and Ia-like antigens in the second trimester of gestation, analysis of variance of our data did not demonstrate statistical significance in the observed changes. Therefore we conclude that the pregnancy-induced suppression of maternal responsiveness towards alloantigens and/or mitogens is not reflected by significant changes in the distribution of circulating mononuclear cells and immunoregulatory T-lymphocyte subsets as defined by the currently available surface marker techniques.

A compound follicular-parafollicular cell carcinoma of the thyroid: a new tumor entity?

An unusual thyroid carcinoma is described, showing structural, histochemical and radioimmunologic features of both a follicular and a parafollicular cell carcinoma. Radioimmunoassay revealed high levels of thyroglobulin in the patient's serum and in extracts from metastatic tumor tissue. Immunoreactive thyroglobulin was demonstrated histochemically in tumor cells. On scanning, pulmonary metastases showed uptake of 131I. Somatostatin and neurotensin immunoreactivity was also revealed histochemically in the tumor and a large proportion of the neoplastic cells were argyrophil. Serum calcitonin level was normal and no immunoreactive calcitonin was found in tumor tissue by radioimmunoassay or histochemically. Light microscopy showed cribriform patterns suggestive of follicular carcinoma as well as solid areas reminiscent of medullary carcinoma. Electron microscopy revealed two types of tumor cells. One type had electron dense granules resembling secretory granules characteristic of polypeptide hormone and/or monoamine producing endocrine cells. The other type had no such granules but showed a prominent vesicular rough endoplasmic reticulum similar to that seen in neoplastic follicular cells. The results suggest two alternative possibilities regarding the histogenesis of the tumor. One would be a mixed neoplasm, resulting from a coincidental malignant change in both follicular and parafollicular thyroid cells. The other, more likely alternative would be that the tumor cells are derived from a common stem cell with the potentiality of differentiating into both follicular and parafollicular adult cells. The finding that both thyroglobulin and somatostatin or neurotensin immunoreactivity occurred together in some tumor cells supports the latter possibility and suggests that at least some follicular and parafollicular cells may have a common precursor origin.

The measurement of antithyroglobulin autoantibodies in the presence of thyroglobulin

An homogeneous phase radioassay (HRA) for antithyroglobulin autoantibodies (TgAb) in serum was investigated. In this method TgAb is allowed to react with 125I-Tg in solution and the immune complexes formed are separated by precipitation with sheep anti-human gammaglobulin. HRA proved to be suitable for the screening of sera prior to thyroglobulin (Tg) radioimmunoassay; being both sensitive, and unaffected by high endogenous levels of Tg. HRA was more sensitive than either of two commercial TgAb kits; a hemagglutination assay (Wellcome Australia Ltd.) and a solid phase radioassay (CIS France). Positive responses were obtained with 4 out of 42 normal subjects (titers up to 1/10), 24 out of 31 with untreated Graves' disease (titers up to 1/10,000) and all out of 18 with Hashimoto's thyroiditis (titers up to 1/10,000). Binding of 125I-Tg was displaceable with added unlabelled Tg, but in no case could it be abolished with less than 1,000 micrograms/l. Some sera exhibited more than one class of binding site and variation in both affinity and capacity for Tg was observed. It was concluded that the use of an assay standard for the reporting of results in units of concentration is invalid, although units of TgAb activity may be used as long as the analytical method is specified. Serum levels of TgAb may also be reported in semi-quantitative terms, such as in this report where a binding titer is used, or alternatively, antigen binding capacity may be reported.

Circulating T-cell subsets in Graves' disease: differences between patients with active disease and in remission after 131I-therapy

In the present investigation some surface markers in peripheral blood T lymphocytes of patients with active Graves' disease and subjects in remission after 131I-therapy have been studied. We confirmed low TG levels in untreated patients and normal values in treated subjects. Increased percentages of DR+, MLR4+ (activated T cells), and 5/9+ (inducer-helper) T cells were detected in patients with active disease, thus indicating the presence of activated T cells and suggesting increased levels of helper T cells. High percentages of MLR4+ and 5/9+, but normal levels of DR+ were found in 131I-treated subjects. The different distribution of DR and MLR4 positivities on 5/9+ and 5+9-T cells confirm the different meaning of these two markers of the activation state. The imbalance of T-cell subsets found in 131I-treated subjects and the normal values observed in patients with hyperthyroidism due to toxic adenoma indicate that hyperthyroidism per se is not sufficient to explain the T-cell alterations. The possible meaning of these findings is discussed with respect to previous hypotheses on the pathogenesis of Graves' disease.

Binding of immunoglobulin-G from patients with thyroid autoimmune disease to normal T lymphocytes

Sera from patients with Graves' disease and Hashimoto's thyroiditis were reacted with normal T lymphocyte preparations in an attempt to detect binding of immunoglobulin G (IgG) to T cells. Sera from normal subjects and patients with toxic adenomas served as controls. Each serum was reacted with at least three different preparations of normal T cells. Bound IgG was identified using a fluoresceinated second antibody, antihuman IgG. Positive cells were enumerated by means of epifluorescent microscopy. IgG from 57.8% of toxic Graves' patients, 30.7% of Graves' patients who were euthyroid after treatment, and 41.6% of Hashimoto's patients bound to normal T cells more than did IgG from normal controls. Reactivity of toxic adenoma sera was similar to that of normal sera. When the positive sera were reacted with helper or suppressor/cytotoxic T cell preparations (separated by negative selection technique), the binding was shown to be directed against suppressor/cytotoxic T cells but not against helper cells. These data indicate that a significant proportion of patients with autoimmune thyroid disease have IgG in their serum which react with a subset of normal T suppressor/cytotoxic cells. This phenomenon could be the expression of anti-lymphocyte antibodies, which may relate to previously recognized reductions in number and function of suppressor T cells in autoimmune thyroid disease.

Influence of thyroid substitution therapy and thyroid autoantibodies on the value of serum thyroglobulin in recurring thyroid cancer

The study was performed to evaluate the influence of thyroxine substitution therapy and the presence of thyroglobulin antibodies (TgAb) on the usefulness of serum thyroglobulin (Tg) measurements in the follow-up of patients treated for well differentiated thyroid carcinoma. Seventy-two consecutive patients with differentiated thyroid cancer and eight with medullary carcinoma as well as controls were studied on one or more occasions and blood was drawn for measurement of serum Tg, TgAb, TSH and thyroid hormones. In 23 patients the hormonal substitution was withdrawn and 3-4 weeks later new blood samples and a 131I scintigraphy was performed. Eighteen patients were shown to have recurrence or metastases. Four of these had TgAb, two had normal Tg values, and the remaining 12 had extremely elevated levels. Those with TgAb and normal Tg values all had high Tg levels off thyroxine substitution. The 54 patients without evidence of recurrence had low levels of serum Tg except for one with highly elevated values. Based on the results from this and other studies is concluded that serum Tg is an important adjunct in the follow-up of patients with well differentiated thyroid carcinoma, but certain limiting factors have to be taken into account, i.e., the radicality of surgery, the sufficiency of the substitution, the presence of TgAb and the method for measurement of Tg.

Lymphocyte subsets defined by monoclonal antibodies in human pregnancy

Using monoclonal antibodies, indirect immunofluorescence, and flow cytometry, the proportions and absolute numbers of various lymphocyte subsets in peripheral blood have been measured in normal human pregnancy. Groups of ten women were studied at 12, 28, and 36 weeks of gestation and compared with 16 nonpregnant control women. The percentage of T cells (OKT3+) was constant throughout pregnancy, and this was confirmed in three women studied serially prior to and throughout early pregnancy. A slight fall in the proportion of helper cells (OKT4+) and rise in the proportion of suppressor cells (OKT8+) was observed at 12 and 28 weeks, but these changes, and the resulting fall in helper/suppressor ratio, were not statistically significant. Absolute lymphocyte counts determined by white cell count and differential were lower during pregnancy. The absolute numbers of T cells, helper cells, suppressor cells, and Ia-bearing cells (mainly B cells) were significantly lower at 36 weeks' gestation. T cells and helper cells were significantly reduced in absolute number at 12 weeks' gestation. There was no change in the ratio of T cells to B cells at any stage of gestation. The lack of any significant change in the balance between helper and suppressor cells in peripheral blood suggests that these cells are not important in the immune adaptation to pregnancy.

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.

Studies of immunoglobulin synthesis in cultures of peripheral T and B lymphocytes: reduced T-suppressor cell activity in Graves' disease

Cellular interactions involved in Graves’disease were studied in patients in different stages of the disease and in normal controls. Synthesis and secretion of immunoglobulin G (IgG) in the supernate of pokeweed mitogen (PWM)‐stimulated cultures of constant numbers of non E rosette forming cells (E− cells) and of increasing numbers of autologous E rosette forming cells (E+ cells) (E+/E− ratios = 1:1, 2:1, 4:1, 8:1, 10:1) were measured by a specific solid‐phase radioimmunoassay. In the normal group, the mean IgG production increased with increasing E+/E‐ ratio (T helper effect), reaching a maximum at a T/B ratio of 4:1, then decreased at higher E+/E− ratios (T suppressor effect). At a E+/E− ratio of 10:1 the IgG synthesis was 39% of the peak value. In the Graves’patients the mean IgG synthesis increased with increasing numbers of E+ cells at every ratio with a peak value found at E+/E− ratio = 10:1. There was no detectable suppressor effect. In three experiments performed with allogeneic combinations of cells, it was observed that the Graves’E− cells were able to respond both to helper and suppressor signals from normal E+ cells, while the Graves’E+ were not able to suppress IgG synthesis by normal E− cells. Treatment of E+ cells with 3,000 cGy of irradiation before adding them to E− cells abolished the suppressor effect seen at the higher E+/E− ratios in the normal controls because of inactivation of the T suppressor lymphocytes. In contrast, the same procedure was without effect on the IgG synthesis by E− cells in Graves’patients. When peripheral blood mononuclear cells (PBMC) were cultured in the presence of PWM and of PWM + Concanavalin‐A (Con‐A), the PWM‐induced synthesis of IgG was suppressed in the presence of Con‐A by 75% (using unfractionated PBMC) and 74% (using E+/E− cells) at 1:1 ratio in normal controls, while Graves’patients’cells caused lower suppression of 66 and 48%, respectively. This latter value was significantly different from that found in the normal group (P < 0·05).

Prevalence of increased intraocular pressure in Graves' disease--evidence of frequent subclinical ophthalmopathy

Graves' exophthalmos is frequently associated with elevated intraocular pressure on upgaze. Eighty patients with Graves' disease were evaluated prospectively by applanation tonometry to assess the prevalence of ophthalmopathy in this disorder. Whereas 21 (26 per cent) of the 80 patients had exophthalmos, 61 (76 per cent) had abnormal intraocular pressure (delta greater than or equal to 3 mm Hg). All patients with exophthalmos had elevated intraocular pressure on upgaze; 40 (68 per cent) of 59 patients without proptosis had abnormal pressure readings. The mean interval between the onset of Graves' disease and this study was 6.3 +/- 1.0 years (S.E.M.) for those patients who had exaggerated positional changes in intraocular pressure, as compared with 3.0 +/- 1.0 years for those with normal intraocular pressure (P less than 0.005). All but 1 of 15 patients in whom the diagnosis of Graves' disease had been documented 10 or more years earlier had increased intraocular pressure on upgaze. We conclude that Graves' ophthalmopathy is more common than is recognized clinically and that eye involvement is an inevitable complication of the disease.

Isolation and characterization of mononuclear cells from various thyroid tissue specimens

Extensive studies of humoral and cell mediated autoimmune responses to thyroid antigens have been performed in order to understand the underlying mechanisms of autoimmune thyroid disorders. Very little is known, however, about the nature of the lymphocyte subpopulations in the thyroid gland and their possible involvement in the pathogenesis of thyroid diseases. We have developed a Percoll gradient technique to separate mononuclear cells from thyroid cells of resected thyroid glands. Thyroid tissue was minced, incubated with Dispase and passed through a tissue sieve. The filtrate was layered onto a four step discontinuous Percoll gradient (densities 1.140, 1.077, 1.061, 1.030 g/ml). Thyroid cells appeared in band II and mononuclear cells in band III. Mononuclear cells were characterized using the monoclonal antibodies OKT-3, OKT-8, OKI-a and OKM-1, and the levels of these populations in peripheral blood and thyroid tissue compared. Patients have been classified by conventional clinical, immunological and histological criteria. The studies involved thyroid tissues from 8 patients with euthyroid nodular goitre, 7 patients with Graves' disease and 1 with Hashimoto's thyroiditis. In the thyroid tissue of non-autoimmune thyroid diseases we find significantly less OKT-3+ cells compared to peripheral blood. In thyroid tissue of autoimmune thyroid diseases there are significantly less OKT-8+ cells compared to peripheral blood. These preliminary results might be linked to the hypothesis of decreased suppressor T-cell activity in autoimmune thyroid disease.

Discrepancy between haemagglutination and radioimmunological techniques for measurement of serum thyroglobulin autoantibodies

Recently, it has been suggested that in some patients with autoimmune thyroid diseases the tanned red cell (TRC) method for detection of thyroglobulin autoantibodies (TgAb) is negative where TgAb measured by radioimmunoassay (RIA) show positive values. To investigate this further, patients with thyroid diseases, pernicious anaemia and a control group were studied for serum concentrations of TgAb by TRC and by quantitative RIA, calibrated against MRC Standard A65/93. Antibodies for microsomes (MAb) were measured immunofluoretically. There was in all patient groups (Hashimoto's thyroiditis (n = 41), Graves' disease (n = 50), idiopathic myxoedema (n = 12), euthyroid Graves' disease (n = 7), pernicious anaemia (n = 81) a discrepancy between TgAb measured by TRC and RIA, respectively, whereas there was a reasonable correlation between the presence of TgAb by RIA and the presence of MAb. A possible interference from antinuclear antibodies and rheumatoid factors was ruled out. There was no increased frequency of TgAb measured by RIA in the control group. Fractionation of TRC negative sera revealed macromolecular TRC-activity, whereas TgAb positive sera by both methods had almost exclusively RIA and TRC activity corresponding to IgG. Based on these results and others it seems that the TRC method for measurement of serum TgAb is of limited diagnostic value. Furthermore, the TRC method is in many cases not sensitive enough for screening for TgAb prior to measurement of serum Tg, which is of importance as this method shows false values in the presence of TgAb due to methodological interference.

Uveal melanomas presenting during pregnancy and the investigation of oestrogen receptors in melanomas

We observed a young woman who showed growth of a choroidal melanoma over the course of 2 pregnancies, with subsequent enucleation of the eye. This is the first such documented case. In addition 4 other women with uveal malignant melanomas presented during pregnancy. This observed number of pregnancies (5) was greater than the expected number (2.1) among women of childbearing age who underwent enucleation with subsequent analysis in our pathology laboratory. However, this difference was not statistically significant. Further, more females 44 years of age or younger underwent enucleation for malignant melanoma than men of comparable age. Evaluation of these cases led us to propose that there is a subset of patients whose ocular melanomas are hormonally responsive. We therefore analysed uveal melanoma and choroidal tissue from 7 patients, including one of the pregnant women, for the presence of oestrogen receptors. No specific oestrogen binding was found. The possibilities that other hormones are involved or an immunological mechanism is operative are discussed.

A comparison of serum thyroglobulin measurements and whole body 131I scanning in the management of treated differentiated thyroid carcinoma

Serum thyroglobulin levels were measured by a sensitive radioimmunoassay in 76 patients whose differentiated thyroid carcinoma had been treated by surgery with or without subsequent administration of radioactive iodine (131I). Examination of the results of 105 concomitant whole body 131I scan results and serum thyroglobulin levels showed a high degree (83.8%) of concordance between these two techniques. A significant correlation (r = 0.670, p less than 0.001) was found between serum thyroglobulin levels and quantitative 131I uptake in the neck and/or metastases in 42 patients in whom this was measured. Although a high degree of congruence was found between the results of 131I scans and the presence or absence of circulating thyroglobulin, 13 patients with negative scans using conventional doses of 131I had measurable levels of thyroglobulin. Eight of these patients had or subsequently developed evidence of residual thyroid tissue or metastatic carcinoma. The measurement of serum thyroglobulin levels in patients previously treated for differentiated carcinoma offers a more convenient and more sensitive method of detecting residual normal or neoplastic thyroid tissue than does whole body scanning in 131I.

A new solid-phase immunoradiometric assay for anti-thyroglobulin autoantibody

A newly developed sensitive and quantitative immunoradiometric assay (IRMA) for anti-thyroglobulin (anti-Tg) autoantibody is described. Serum samples to be tested are added to wells of polyvinyl microtiter plates coated with human thyroglobulin. After removal of the unbound material, anti-Tg antibody is determined by adding purified 125I-anti-human immunoglobulin G antibody. Using 1.0 microliter of serum anti-Tg antibody was detected in 81.2% of patients with Hashimoto's thyroiditis or idiopathic myxedema (n = 32), in 46.4% of those with Graves' disease (n = 28), in 11.9% of subjects with other thyroid disorders (n = 42) and in 4.2% of normal controls (n = 71). Similar percentages of positive tests were observed by passive hemagglutination (PH) and a good correlation was found between the antibody levels determined by the two techniques. Using larger amounts of serum (100 microliters) detectable anti-Tg antibody by IRMA was found in the majority of patients with thyroid autoimmune disorders who had negative PH tests. Quantitative measurements of anti-Tg antibody by IRMA could be obtained by using purified anti-Tg antibody as standard reference. The minimum detectable amount of anti-Tg antibody was 0.5 ng. The present method is proposed as a simple and convenient technique for quantitative measurement of any antibody, using wells coated with the appropriate antigen.

The value of serum thyroglobulin measurement as a marker of cancer recurrence in the follow-up of patients previously treated for differentiated thyroid tumor

In order to verify the value of serum thyrogolbulin (hTg) determination to detect cancer recurrence, 104 patients previously treated with surgical and 131I total thyroid ablation of differentiated thyroid cancer were studied. Comparison of serum hTg results and 131I total body scans (131I TBS) was attempted. In 87 patients with negative 131 I TBS, serum hTg was undetectable in 80% of the patients whereas in 20% detectable amounts of hTg were measured. In 57 patients with positive 131I TBS, serum hTg was measurable in 72% of the patients whereas in 20% was undetectable. These contrasting results of serum hTg measurement and 131I TBS suggest to us the usefulness to use both tests in the detection of thyroid cancer recurrence.

Changes of circulating thyroid autoantibody levels during and after the therapy with methimazole in patients with Graves' disease

The changes occurring in the levels of circulating thyroid microsomal antibody (M-Ab) and antithyroglobulin antibody (Tg-Ab) during antithyroid drug therapy were studied in 32 patients receiving methimazole for Graves' disease. M-Ab was determined by competitive binding radioassay and Tg-Ab by a sandwich radiometric method. Before treatment 25 subjects (78.1%) had abnormally elevated (greater than or equal to 75 U/ml) M-Ab levels. A more than 30% reduction of M-Ab concentration with respect to the pretreatment value was found in 16 (64.0%) of these patients within the first 3-5 months of therapy, in 23 (92.0%) within 8-11 months and in 21 (84.0%) at the end of treatment (16-18 months). No change was found in the 7 patients with initial M-Ab levels less than 75 U/ml. The reduction of M-Ab was more pronounced in the patients with good control of thyrotoxicosis than in those who were still hyperthyroid or were rendered hypothyroid during treatment. Twenty-three patients were followed after completion of the course of methimazole therapy, and 13 of them showed relapse of hyperthyroidism. A significant rise of M-Ab with respect to the values observed at the end of treatment occurred in all relapsing patients who had abnormally elevated M-Ab levels before therapy. With one exception, no M-Ab increase was found in the 10 nonrelapsing patients. However, no difference between relapsing and nonrelapsing patients was observed when the M-Ab changes occurring during treatment were considered. A similar trend during and after withdrawal of therapy was noted for Tg-Ab but, because of the relatively small percentage of positive subjects (25%), the results were less conclusive. The present data indicate that methimazole treatment induces a fall of thyroid antibodies in patients with Graves' disease, and that relapse of hyperthyroidism is associated with an increase of these antibodies. However, the antibody changes occurring during treatment showed no prognostic value in predicting the outcome of therapy.

The comparative value of serum thyroglobulin measurements and iodine 131 total body scans in the follow-up study of patients with treated differentiated thyroid cancer

This study is an attempt to unify the evaluation of patients with well-differentiated thyroid cancer after ablative therapy. As such serum thyroglobulin determinations on and off thyroid hormone (T4) therapy and iodine 131 total body scans were examined in 53 patient studies. No metastases were found in patients whose thyroglobulin value was undetectable (less than 1 ng/ml). Values during T4 therapy that were detectable, even as low as 4.2 ng/ml, were occasionally associated with metastases. After T4 withdrawal, thyroglobulin value and scan were obtained. Neither metastasis nor clinically detectable cancer was found in patients whose thyroglobulin value was less than 10 ng/ml while off T4. Conversely, a value greater than 10 ng/ml was often associated with documented metastases even when the scan was negative. In summary, a thyroglobulin value less than 1 ng/ml during T4 therapy or less than 10 ng/ml off T4 therapy suggests successful therapy and a routine scan could be avoided unless clinically indicated. However, a value greater than 10 ng/ml suggests the presence of metastasis despite a negative scan. Thyroglobulin determination substantially improves the management of these patients.

Serum thyroglobulin in thyroid cancer

Serum thyroglobulin (Tg) was measured in 274 patients with differentiated thyroid cancer; 266 had previous thyroidectomy, which had been followed by ablative iodine-131 in 183 cases. Neither the presence nor the titre of anti-Tg antibodies appeared to affect Tg assays. Serum Tg reflected the presence or absence of cancer in 83% of 164 patients not receiving thyroxine (T4). This concordance improved to 97.5% in 158 patients tested while receiving T4. 34 patients in remission were tested both on and off T4 therapy; in all these patients the Tg level when receiving T4 was less than 5 micrograms/l. In 19 of 21 patients with cancer T4 treatment did not suppress Tg. Serum Tg thus provides an excellent marker for the presence or absence of thyroid cancer in patients taking T4, even if anti-Tg antibodies are present. It is proposed that monitoring of patients by assay of serum Tg should supplant routine assessment by radioactive-iodine scans of the neck or whole body.

Thyroid carcinoma following treatment for acute lymphoblastic leukemia

A 2 1/2-year-old girl with acute lymphoblastic leukemia received chemotherapy and prophylactic cranial irradiation. After six years of remission, including three years off therapy, metastatic thyroid carcinoma appeared in the cervical lymph nodes. The predisposing factors for the development of thyroid carcinoma as a second malignancy in this case are discussed. It is suggested that thyroid carcinoma should be added to the growing list of second malignancies in acute lymphoblastic leukemia and that careful thyroid examination be included in the follow-up of long-term survivors.

Further observations on radioimmunoassay for thyroglobulin-binding capacity in human serum

A simplified radioimmunoassay for measuring thyroglobulin-binding capacity in human serum is described. Thyroglobulin (Tg) is labelled with lactoperoxidase (specific activity 5 microCi/microgram) which makes it possible to measure a binding capacity of more than 10 ng/ml of serum. The standard curve is plotted measuring the percentage of bound 125I-Tg against the dilution of 1 mg/ml Tg capacity from a pool of Tg antibodies from different individual serum samples. When polyethyleneglycol and a second antibody were compared in their precipitation of the immune complexes, the latter provided a better precipitation. The stability of the labelled Tg stored at --20 degrees C was checked at different intervals of time by ultracentrifugation and immunoreactivity. It was found that the labelled Tg can be used up to one month after iodination. Fragments produced during storage at --20 degrees C only partially reacted with Tg antibodies. Screening of 300 serum samples was performed by haemagglutination and binding capacity; of 45 positive serum samples, 28 were positive only by binding capacity, thus demonstrating that this method is far more sensitive, accurate and precise than those currently employed.

A new solid-phase radioimmunoassay to measure IgG secreted by cultured human lymphocytes

We describe a simple solid-phase radioimmunoassay (RIA) to detect IgG based on competitive binding between radiolabeled and unlabeled IgG for anti-IgG antibody physically adsorbed to the wells of polyvinyl microtiter plates. The assay is sensitive (1 ng), rapid, and is particularly suited for studies of in vitro IgG secretion by human peripheral blood lymphocytes, since such studies require large numbers of cultures. Conditions which permit measurement, by means of this assay, of helper and suppressor T cell effects on IgG production by human B cells in culture are described.

Serum thyroglobulin in thyroid carcinoma and other thyroid disorders

Measurements of serum thyroglobulin (hTg) were performed using a specific radioimmunoassay. Sera with detectable anti-thyroglobulin (anti-Tg) antibody titers (> or = 1:10) as assessed by passive hemagglutination were discarded. Assays were carried out under conditions in which anti-Tg titers less than 1:10 produced no interference. The assay sensitivity was 1.25 ng/ml and the mean +/- SE concentration of serum hTg in 58 control subjects was 9.5 +/- 0.9 ng/ml (range < 1.25-27 ng/ml). A slight but significant (p < 0.025) increase in the mean hTg level was observed in 12 pregnant women at delivery (25.7 +/- 5.2 ng/ml). Moderate to marked elevations of serum hTg were observed in patients with nontoxic goiter (61.4 +/- 15 ng/ml; n = 23), subacute thyroiditis (138 +/- 67 ng/ml; n = 5), toxic adenoma (129 +/- 47 ng/ml; n = 13), untreated (424 +/- 101 ng/ml; n = 35) or treated (328 +/- 222 ng/ml; n = 14) toxic diffuse goiter. 88 patients with thyroid carcinoma and 10 with nonthyroidal malignancies were studied. The mean level of serum hTg was increased in untreated differentiated thyroid carcinoma (89.5 +/- 19 ng/ml; n = 13) but not in undifferentiated (10 +/- 2.9 ng/ml; n = 6) or medullary (0.8 +/- 0.2 ng/ml; = 3) carcinoma. In treated differentiated thyroid carcinoma the mean hTg levels were normal (8.2 +/- 0.2 ng/ml) in patients (n = 24) with no evidence of either a thyroid residue or metastatic disease, moderately increased (56.6 +/- 16 ng/ml) in patients (n = 27) with residual thyroid tissue, markedly elevated in patients with lymph node metastases (199 +/- 50 ng/ml; n = 5) and extremely elevated in those with bone (4004 +/- 982 ng/ml; n = 8) or lung (2520 +/- 620 ng/ml; n = 5) metastases. There was no significant difference in serum hTg between functioning (n = 23) and nonfunctioning (n = 5) metastases as assessed by 131I whole body scan. A slight but significant (p < 0.0005) increase in the mean concentration of hTg was observed in nonthyroidal malignancies (21.7 +/- 4.5 ng/ml; n = 10). Serial measurements showed a transient increase of serum hTg after 131I therapy of differentiated thyroid carcinoma, toxic diffuse goiter or toxic adenoma, with peak values usually occurring within the first three days. A fall of serum hTg after administration of suppressive doses of thyroid hormone to patients with nontoxic goiter and a rise after discontinuation of thyroid suppressive therapy in patients with metastatic differentiated thyroid carcinoma was observed.(ABSTRACT TRUNCATED AT 400 WORDS)

An enzyme immunoassay for the measurement of anti-thyroglobulin autoantibody in human serum

An enzyme-linked sandwich immunoassay using human thyroglobulin conjugated with beta-D-galactosidase and silicone rods coated with human thyroglobulin was developed for the measurement of circulating anti-thyroglobulin autoantibody. The volume of serum needed for the assay was as little as 5 microliter. The sensitivity of the assay was approximately 7 x 10(-15) mol/tube of antithyroglobulin immunoglobulin G corresponding to 220 ng/ml of serum, which was equal to or rather higher than that of radioimmunoassay. The specificity of the assay was demonstrated by (1) parallelism of the standard curve with dilution of sample sera of patients with thyroid diseases, and (2) non-detectability of anti-thyroglobulin in autoantibody in the sera of normal subjects. The precision of the assay was proven by (1) sufficient recovery of antithyroglobulin immunoglobulin G added to serum, and (2) coefficients of variance within and between assays were 6.5 to 10.3% and 4.9 to 14.1%, respectively. No effect of thyroglobulin on the present assay was observed when the ratio of the amount of thyroglobulin to that of anti-thyroglobulin immunoglobulin G was lower than 1 : 10. Furthermore, a significant correlation was observed between anti-thyroglobulin autoantibody concentrations measured by our enzyme immunoassay and those by tanned red cell hemagglutination (r = 0.78), and between those by the enzyme immunoassay and those by radioimmunoassay (r = 0.80). The application to clinical samples ensured the high sensitivity and the adequate validity of the present assay.