THYROID FUNCTION IN CHORIOCARCINOMA: DEMONSTRATION OF A THYROID STIMULATING ACTIVITY IN SERUM USING FRTL-5 and HUMAN THYROID CELLS

Hyperthyroidism is a well recognized complication of gestational trophoblastic tumours (GTT) and may be due to high circulating concentrations of human chorionic gonadotrophin (hCG) or its variants. We have studied 24 clinically euthyroid women with GTT. Eight were biochemically hyperthyroid with low or undetectable serum thyrotrophin (TSH) and had a mean serum hCG of 361.2 x 10(3) IU/l compared to 76.2 x 10(3) IU/l in the other patients (P less than 0.01). Purified hCG stimulated iodide uptake into FRTL-5 cells with 25 x 10(3) IU/l being equivalent in potency to 1 mU/l of thyrotrophin (TSH). Sixteen out of the 24 sera (67%) stimulated iodide uptake when applied to the cells at a 1:10 dilution. Sera from all eight hyperthyroid patients contained thyroid stimulating activity. The mean hCG concentration in the 16 stimulatory sera was 238.2 x 10(3) IU/l compared to 37.1 x 10(3) IU/l in the other eight sera (P less than 0.01). Six men with hCG-secreting testicular tumours were biochemically euthyroid although three of their sera stimulated iodide uptake into FRTL-5 cells. In human thyroid cells the mean cAMP production over 4 h with sera from five healthy controls was 54.2 +/- 1.81 pmol/mg cell protein compared to 67.0 +/- 3.8 pmol/mg protein with sera from five choriocarcinoma patients (P less than 0.02). Serum from patients with gestational trophoblastic tumours contains a thyroid stimulating activity which may be hCG and whose presence correlates with hyperthyroidism.     

环磷酸腺苷中介对甲状腺功能和生长的双重刺激作用

选用4种公认能增加细胞内cAMP的物质作用于鼠甲状腺细胞,测定~(125)Ⅰ摄取作为一种功能指标,测定DNA和~aH-TdR摄取作为生长指标,具有以下共同特点:(1)既刺激甲状腺功能,又刺激甲状腺生长;(2)在下述浓度的各种实验物质对甲状腺细胞的功能刺激和生长刺激作用同时达到最大效应:Forskolin为5×10~(-6)mol/L、霍乱毒素(cholera toxin)为5×10~(-11)mol/L、异丁基甲基黄嘌呤(IBMX)和二丁基环磷酸腺苷[(Bu)_2cAMP]均为5×10~(-4)mol/L。提示对甲状腺的功能刺激和生长刺激作用由以上4物的共同生物效应物质cAMP所中介。     

COMPARATIVE EVALUATION OF CYCLIC AMP AND IODIDE ACCUMULATION RESPONSES TO THYROID-STIMULATING IMMUNOGLOBULINS IN CULTURED FRTL-5 CELLS

The rat thyroid cell strain FRTL-5 was used to investigate the relationship between cyclic AMP and iodide accumulation responses to thyroid-stimulating immunoglobulins (TSIg). Immunoglobulin G-enriched precipitates of sera from 19 of 21 (90%) newly-diagnosed Graves' disease patients gave significant (P less than 0.01) accumulation of iodide (125I), and 16 of these also stimulated intracellular cyclic AMP. Correlation was poor however, with certain TSIg preparations giving widely divergent responses. After initiation of antithyroid treatment, 40% of sera investigated contained TSIg detectable in both bioassay systems, and all but one of the remainder were stimulatory in one of the two bioassays. All patients in remission were devoid of detectable TSIg as determined by iodide accumulation, although a single preparation stimulated cyclic AMP accumulation. LATS-B, a lyophilized reference serum preparation containing high TSIg activity, enhanced iodide accumulation, which showed evidence of correlation with intracellular cyclic AMP at doses above 0.5 mU/ml. At lower doses, iodide accumulation was observed in the absence of detectable cyclic AMP accumulation. TSH and LATS-B-induced iodide accumulation were enhanced, and iodide efflux reduced, by the anion channel blocker 4-4' diisothiocyanate stilbene 2,2' disulphonic acid (DIDS). In contrast, Ig-enriched fractions of normal sera decreased both basal and stimulated iodide accumulation, but were without effect on efflux. TSIg from untreated Graves' sera gave widely-differing iodide accumulation responses which showed poor correlation with both intracellular cyclic AMP and cyclic-AMP-independent iodide efflux. This clear dissociation of responses to serum Ig preparations suggests that iodide uptake in FRTL-5 cells, which do not organify iodide, may be subject to variable effects of non-TSIg components of Graves' sera, on both iodide uptake itself, and as inhibitors of TSIg-induced accumulation of intracellular cyclic AMP.     

用不提取血清刺激人甲状腺细胞cAMP的生成测定甲状腺刺激性抗体

用不提取的血清刺激培养的人甲状腺细胞cAMP的生成测定甲状腺刺激性抗体。结果显示,甲状腺刺激性抗体的阳性率在未治的Graves病患者为83.3％(25/30),抗甲状腺药物治疗的Graves病患者为43.8％(7/6),正常人为4％(1/25)。单纯性甲状腺肿和甲状腺腺瘤患者甲状腺刺激性抗体均为阴性。提示用本法检测Graves病患者的甲状腺刺激性抗体具有较高的敏感性和特异性。     

自身免疫甲状腺病单个核细胞体外培养产生抗甲状腺球蛋白抗体

利用ELISA技术检测自身免疫甲状腺病(AITD)患者周围血单个核细胞(PBMC)体外培养产生甲状腺球蛋白抗体(TGA)。结果表明:体外培养AITD患者PBMC能够产生可测出的TGA,阳性率31.25％。桥本甲状腺炎(HT)较Graves甲亢(GD)更易体外产生TGA,阳性率分别为44.19％和16.22％。美洲商陆刺激体外产生TGA增加,而可溶性甲状腺球蛋白对体外产生TGA无刺激作用。抗甲状腺药物他巴唑能够抑制体外产生TGA。HT患者血清TGA水平与体外产生TGA呈正相关,但未观察到GD患者血清TGA与体外产生TGA的相关性。提示AITD患者体内存在可引起自身抗体产生的免疫调节紊乱、HT与GD在产生自身抗体的机制上可能有所不同。     

SUPPRESSION AND STIMULATION OF IMMUNOGLOBULIN SYNTHESIS BY AGENTS PRESENT IN RHEUMATOID SYNOVIAL EFFUSIONS

Synovial effusions from 14 patients with rheumatoid arthritiscontain factors capable of enhancing and suppressing the productionof immunoglobulin when added to normal peripheral lymphocytecultures in vitro. Utilizing a radioactive immune coprecipitationtechnique it could be demonstrated that enhancement was observedupon addition of relatively small amounts of synovial fluid,while addition of higher amounts resulted in suppression ofimmunoglobulin synthesis. Nine of ten non-rheumatoid joint effusionsshowed neither enhancing nor suppressing activities. The possiblerelationship of these events to lymphokine production in thejoint is discussed.     

METHOTREXATE ACTION IN RHEUMATOID ARTHRITIS: STIMULATION OF CYTOKINE INHIBITOR AND INHIBITION OF CHEMOKINE PRODUCTION BY PERIPHERAL BLOOD MONONUCLEAR CELLS

This open label study examines whether methotrexate (MTX) treatmentmodulates ex vivo synthesis of interleukin-1 receptor antagonist(IL-lra), soluble tumour necrosis factor receptors(sTNFR p55and p75), interleukin-1ß (IL-1ß), tumournecrosis factor     

THE INVOLVEMENT OF THE PENTOSE SHUNT IN THYROID METABOLISM AFTER STIMULATION WITH TSH OR WITH IMMUNOGLOBULINS FROM PATIENTS WITH THYROID DISEASE. 1. THE GENERATION OF NADPH IN RELATION TO STIMULATION OF THYROID GROWTH

It has been shown previously that both thyrotrophin (TSH), and also immunoglobulins (Ig) derived from patients with goitrous Graves’disease, stimulate DNA-synthesis in guinea-pig thyroid tissue maintained in vitro. Here we describe the use of the same in vitro system and methods of quantitative cytochemistry to test the effect of these substances on the generation of NADPH, which is another indicator of the potential for growth. As could be predicted by its trophic action, TSH stimulated the generation of NADPH by glucose 6-phosphate dehydrogenase. The Ig-fraction from normal subjects depressed this activity. The Ig-fraction from Graves’disease patients with goitres stimulated the generation of NADPH, whereas the Ig from patients with Graves’disease but with minimal enlargement of the thyroid gland behaved like normal Ig. A similar lack of stimulation was found with Ig from patients with Pendred's syndrome, other dyshormonogenetic goitres, and autonomous single adenomas. In all specimens tested, there was good correlation between the amount of DNA-synthesis, measured by Feulgen cytophotometry, and the activity of glucose 6-phosphate dehydrogenase activity that generated NADPH. These results support the concept that there is a distinct type of autoantibody that influences thyroid growth.     

BREAST STIMULATION IN CYCLING WOMEN, PREGNANT WOMEN AND A WOMAN WITH INDUCED LACTATION: PATTERN OF RELEASE OF OXYTOCIN, PROLACTIN AND LUTEINIZING HORMONE

Levels of oxytocin (OT) and PRL were measured in plasma drawn before and during intermittent mechanical pump and tactile stimulation of the breast in five normal cycling women and 19 women in the third trimester of pregnancy. OT was significantly increased above baseline in response to breast stimulation in two of five cycling women and PRL increased in one of the two OT responders. In pregnant women, mean OT post nipple stimulation was significantly higher than pre nipple stimulation whereas PRL did not increase significantly. The response of OT to nipple stimulation occurred in 18 of 19 pregnant women compared to only two of five normal cycling women but the magnitude of the OT response in pregnant women was less than in cycling women or post-partum lactating women previously studied in this laboratory. In one non post-partum woman who induced lactation for the purpose of breast-feeding an adopted infant, OT and PRL were measured before and during mechanical pump and tactile stimulation before initiation of breast-feeding. OT increased during mechanical pump and tactile stimulation of the breast, as well as suckling, whereas PRL increased only in response to suckling. Levels of LH were measured in plasma every 20 min for 160 min at the following times: before initiation of breast-feeding, during induced lactation while breast-feeding, and 30 d after discontinuation of breast-feeding. Despite the development of oligomenorrhoea during the period of breast-feeding, levels of progesterone were not suppressed and LH was released in a normal pulsatile fashion.     

SERUM LEVELS OF PROLACTIN AND MILK PRODUCTION IN WOMEN DURING A LACTATION PERIOD OF THIRTY MONTHS

Serum prolactin was measured in single blood samples collected from 219 nursing mothers of the Kivu region (Zaïre) during 30 post-partum months. In addition the number of feeding episodes per day and the amount of milk given to the child in 24 h were recorded. The mean serum prolactin levels remained around 1000 mu/l during the first 15 months of lactation and fell during the next 3 months to 550 mu/l. A decline in milk production per day occurred during the second year, but it was less marked than that of prolactin. This decline seemed to be associated with the decline in suckling frequency as the quantity of milk given per feed remained almost unchanged throughout lactation. The average amount of milk given by mothers with serum prolactin levels in the range of values seen in non-lactating and non-pregnant women (about 500 mu/l) is nevertheless of some 35 g per feeding or 260 g per day. These results demonstrate that milk production can be maintained in women with normal levels of prolactin and suggest that prolactin plays a permissive role in established lactation.     

SIMULTANEOUS ASSAY OF THYROID ADENYLATE CYCLASE- AND GROWTH-STIMULATING ANTIBODIES USING FRTL-5 CELLS. EVIDENCE SUGGESTING THEIR IDENTITY IN PATIENTS WITH GRAVES'' DISEASE

The relationship between thyroid growth-stimulating antibodies (TGSAb) and thyroid adenylate cyclase-stimulating antibodies (TSAb) in patients with Graves' disease is still a matter of controversy. To investigate this problem, we have developed an assay for the simultaneous measurement of TSAb and TGSAb using FRTL-5 cells. TSAb was detected by its ability to stimulate iodide (I-) uptake and TGSAb by the 3H-thymidine ([3H]-Tdr) incorporation assay. Thirty-four immunoglobulin G (IgG) preparations from patients with active Graves' disease were selected from a previous series in order to include both TSAb-negative IgGs (n = 9) and TSAb-positive IgGs (n = 25) by the cAMP stimulation assay, with a wide range of stimulatory activity. With one exception, the TSAb-positive IgGs produced a significant stimulation of I- uptake; 20 of them were also TGSAb-positive. The nine IgGs negative in the cAMP assay, were also negative in the I-uptake and the [3H]-Tdr incorporation assays. The majority of samples had a similar potency in the two assays and a significant positive correlation was found (r = 0.76; P less than 0.001). Two IgGs previously shown to inhibit TSH-stimulated adenylate cyclase in FRTL-5 cells produced an almost complete inhibition (80-90%) of both TSH- and Graves' IgG-stimulated I- uptake and [3H]-Tdr incorporation. In conclusion, using a simultaneous assay for thyroid growth and adenylate cyclase stimulation, TGSAb in Graves' patients were found only in TSAb-positive IgGs; both Graves' IgG-stimulated activities were inhibited by antibodies blocking the TSH-dependent adenylate cyclase stimulation. Our data strongly suggest that the same antibody may be responsible for both goitre and thyroid hyperfunction of Graves' disease.     

IODIDE ORGANIFICATION DEFECT IN A COLD THYROID NODULE: ABSENCE OF IODIDE EFFECT ON CYCLIC AMP ACCUMULATION

A follicular adenoma of the thyroid was 'hot' one hour after ^99mTc pertechnetate administration, but 'cold'24 h after ¹³¹I iodide administration. Incubation of the tissue in vitro demonstrated a defect in iodide binding to proteins that was abolished by addition of an H2O2 generating system. In this tissue iodide failed to inhibit TSH-induced cyclic AMP accumulation. The results show that iodide oxidation is required for its inhibitory action on cyclic AMP accumulation in human thyroid.     

PROSTACYCLIN PRODUCTION BY HUMAN UMBILICAL VEIN ENDOTHELIUM IN RESPONSE TO SERUM FROM PATIENTS WITH SYSTEMIC SCLEROSIS

Sera from 29 patients with systemic sclerosis and 30 normalcontrols were examined for their effect on prostacyclin releaseby human umbilical vein endothelial cells during periods ofresponse of 15 min and 72 h and for their effect on endothelialgrowth and ³H-thymidine uptake during a 72-h culture period.In contrast to previous reports, no significant differenceswere detected between patient and control sera in their effecton endothelial cell prostacyclin release, growth or ³H-thymidineuptake. KEY WORDS: Scleroderma, Endothelial cells, Blood vessels, Prostanoid metabolism     

STIMULATION BY GROWTH HORMONE OF SOMATOSTATIN RELEASE FROM THE RAT HYPOTHALAMUS IN VITRO

SUMMARY Growth hormone (GH) has been shown to cause a dose-dependent increase in the release of immunoreactive somatostatin from the rat hypothalamus in vitro, thus providing further evidence that GH may be involved in a ‘short loop’ feedback, controlling its own secretion via hypothalamic somatostatin release.     

THE INVOLVEMENT OF THE PENTOSE SHUNT IN THYROID METABOLISM AFTER STIMULATION WITH TSH OR WITH IMMUNOGLOBULINS FROM PATIENTS WITH THYROID DISEASE. II. THE REOXIDATION OF NADPH AND STIMULATION OF HORMONE SYNTHESIS

Reducing equivalents derived from the tissue re-oxidation of NADPH (NADPH-diaphorase) have been implicated in the peroxidation that is involved in the organification of iodine in the production of thyroid hormones. Immunoglobulin (Ig) fractions from patients with thyroid diseases and from normal controls, in a standard dose of 125 μg/ml and 0±3 μ/ml thyrotrophin (TSH) were incubated with segments of guinea-pig thyroid gland maintained in vitro. A quantitative cytochemical study was made on how these fractions influenced the enzyme activity. A good correlation was found between the ability of such Ig fractions to stimulate the NADPH-diaphorase activity and (1) the degree of hyperthyroidism in the patients and (2) the amount of T3 secreted by the thyroid segments in vitro.     

STIMULATION OF VON WILLEBRAND FACTOR ANTIGEN RELEASE BY IMMUNOGLOBULIN FROM THROMBOSIS PRONE PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND THE ANTIPHOSPHOLIPID SYNDROME

The level of von Willebrand factor angtigen (vWF) released byendothelial cells in response to IgG isolated from 18 patientswith systemic lupus erythematosus (SLE), eight patients withthe anti-phospholipid syndrome (APS) and 22 controls has beenmeasured. Incubation with IgG from the combined patient groupresulted in a significantly greater release of vWF (mean stimulationindex ± SEM, 4.57 ± 0.78) when compared with controls(1.96 ± 0.22, P = 0.003).Furthermore, IgG from 17 patientswho had had a history of thrombosis induced higher levels ofvWF release (5.33 ± 1.09) when compared with the controls(P = 0.008). These findings suggest that IgG from patients withSLE or APS is capable of stimulating vWF release and that thisability may be implicated in the thrombotic events that areobserved in these conditions KEY WORDS: von Willebrand factor antigen, Systemic lupus erythematosus, Anti-phospholipid syndrome, Endothelium, Immunoglobulin     

东方田鼠血清及其不同部分对日本血吸虫童虫的体外杀伤作用

目的 对东方田鼠血清及其不同部分对日本血吸虫童虫的体外杀伤的可能机制进行初步探讨。方法 将血清初步分离成含蛋白部分及分子量小于20kDa的小分子部分，并分别观察了东方田鼠全血清、去补体血清、蛋白及小分子血清成分对体外培养童虫的杀伤，此外，还观察了蜕皮素对东疗田鼠血清杀伤作用的影响。结果 东方田鼠热灭活去补体血清对童虫的杀伤显著低于正常血清；感染及正常东方田鼠血清小分子在第48h及72h表现出一定杀伤作用(30％)，而血清蛋白在24h就有显著杀伤，但杀伤作用略低于全血清；蜕皮素对东方田鼠血清的杀伤无明显影响。结论 补体在东方田鼠血清杀伤机制中有重要作用。血清蛋白为体外杀伤的主要成分，可能与小分子成分协同参与杀伤。     

A STIMULATION BY CYCLIC 3′,5′-ADENOSINE MONOPHOSPHATE OF AMINO ACID ACTIVATION AND POLYMERIZATION IN RETICULOCYTE HEMOLYSATES

With reticulocyte supernatant, cyclic 3',5'-adenosine monophosphate at concentrations of 10(-3) to 10(-2)M causes stimulation of aminoacyl-tRNA synthetases for some, e.g., valine and leucine, but not all, amino acids; it is highest at nonsaturating concentrations of ATP. Similar concentrations of cyclic 3',5'-adenosine monophosphate are found to stimulate phenylalanine polymerization from phenylalanyl transfer ribonucleic acid on polyuridylic acid-charged reticulocyte ribosomes. The degree of stimulation is highest at low GTP concentrations. It is abolished by addition of phosphoenolpyruvate + pyruvate kinase, which stimulate similarly or more effectively at low GTP levels. Under the conditions of these experiments, cyclic 3',5'-adenosine monophosphate did not appreciably inhibit GTP hydrolysis.     

不同外周血标本中HCV RNA检出比较

对５４例抗－ＨＣＶ阳性患者，用多聚酶链反应（ＰＣＲ）技术检测其外周血不同检材（血清、血浆、外周血单核细胞）中ＨＣＶ ＲＮＡ，结果检出率分别为５９．３％、５０％、５５．６％，以血清标本检出率最高。外周血单核细胞（ＰＢＭＣ）中亦有较高的检出率，且在部分（６％）血清测不到ＨＣＮ ＲＮＡ时，ＰＢＭＣ中可测及，提示ＰＢＭＣ可贮存ＨＣＶ ＲＮＡ。     

THE EFFECT OF BLOOD LEUCOCYTES FROM PATIENTS WITH HASHIMOTO''S DISEASE ON HUMAN THYROID CELLS IN MONOLAYER CULTURE

Peripheral blood leucocytes from healthy subjects (control leucocytes) and from patients with Hashimoto's thyroiditis or idiopathic myxoedema, were incubated with 2-3-day-old human thyroid cells in monolayer cultures. After 5-6 days the Hashimoto leucocytes appeared to induce more thyroid cell destruction than control leucocytes. Thyroid cell function (measured by cell to medium (C/M) ratios of ¹³¹I) was reduced in cultures incubated with Hashimoto leucocytes, compared to those incubated with control leucocytes. This effect was not mediated by liberation of thyroid antibodies into the medium, but rather from a direct leucocyte/thyroid cell interaction with a resultant liberation of lysozymes. Preliminary observations indicated that the effect of the Hashimoto leucocytes on thyroid cells could be prevented by prior incubation of the former with anti-thymocyte globulin; this suggested that sensitized lymphocytes may be directly responsible for the thyroid tissue injury of Hashimoto's disease, perhaps with the adjunctive cooperation of the non-specific macrophages. Leucocytes from patients with idiopathic myxoedema (with low or absent circulating thyroid antibodies) did not have any effect on the thyroid cells, perhaps because the concentration of peripheral sensitized lymphocytes may possibly have declined in these patients.