The mechanism for the discrepancy between serum total and free thyroxine values induced by autoantibodies: Report on two patients with Graves' disease

1990 ◽  
Vol 123 (2) ◽  
pp. 123-128 ◽  
Author(s):  
Makoto I Iitaka ◽  
Nobuhiko Fukasawa ◽  
Yoshihito Hara ◽  
Morifumi Yanagisawa ◽  
Kazumasa Hase ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Light Chain ◽  
Immunoglobulin G ◽  
Specific Radioactivity ◽  
Binding Activity ◽  
High Serum ◽  
Graves Disease ◽  
Dependent Manner ◽  
Serum Free ◽  
Dose Dependent

Abstract. The sera from two patients with Graves' disease gave abnormally high serum free T4 values as compared with the total T4 and other hormone values, suggesting the presence of autoantibodies to labelled T4 analogue used in the Amersham free T4 assay kit. The autoantibodies appeared to develop after the initiation of methimazole therapy and disappeared again after the cessation of methimazole. This binding activity to labelled T4 analogue was demonstrated to be in the immunoglobulin G with a k light chain isotype in both sera, and was displaced by unlabelled T4 in a dose-dependent manner. The binding of immunoglobulin G purified from these sera to labelled T4 or T4 analogue was found to be almost identical to that of the corresponding serum binding. Since the specific radioactivity of labelled T4 analogue used in the Amersham free T4 assay kit is about 10 times higher than that of the labelled T4 in the Amersham total T4 assay kit, serum free T4 determinations are much more vulnerable to thyroid hormone autoantibodies. Thus, in the presence of autoantibodies, a large discrepancy develops between free T4 and total T4 values.

5,5'-Diphenylhydantoin decreases the entry of 3,5,3'-triiodo-L-thyronine but not L-thyroxine in cultured GH-producing cells

1988 ◽  
Vol 117 (3) ◽  
pp. 392-398 ◽  
Author(s):  
Leonard R. Zemel ◽  
David R. Biezunski ◽  
Lawrence E. Shapiro ◽  
Martin I. Surks
Keyword(s):  
Plasma Membrane ◽  
Thyroid Hormone ◽  
Dependent Manner ◽  
Exit Rate ◽  
Entry And Exit ◽  
Serum Free ◽  
Fractional Rate ◽  
Serum Free Conditions ◽  
Kinetics Of ◽  
Dose Dependent

Abstract. We determined the effect of 5,5'-diphenylhydantoin (DPH) on the kinetics of T3 and T4 uptake in cultured GH-producing (GC) cells under serum-free conditions. GC cells accumulated [125I]T3 at a greater fractional rate than [125I]T4. The t½ of exit of [125I]T4 and [125I]T3 previously equilibrated in GC cells was 28 min for T4 and 66 min for T3. T3 and T4 entry rates were not influenced by up to a 10 000-fold molar excess of nonradioactive T3, T4, d-T4, rT3, 3,5-T2 and diiodotyrosine. Thus, entry of T3 and T4 in GC cells appeared nonsaturable and was not influenced by various thyroid hormone analogues. DPH, 25–200 μmol/l, decreased the rate of T3 entry in a dose-dependent manner and did not influence the T3 exit rate. At 200 μmol/l DPH, T3 entry decreased by 40%. Rates of entry and exit of T4 were unaffected by DPH. DPH may affect T3 and T4 entry differentially at the level of the plasma membrane.

Immunoglobulins from Graves' disease patients stimulate phospholipase A2 and C systems in FRTL-5 and human thyroid cells

1996 ◽  
Vol 135 (3) ◽  
pp. 322-327 ◽  
Author(s):  
Mohamed A Atwa ◽  
Robert C Smallridge ◽  
Henry B Burch ◽  
Irene D Gist ◽  
Rui Lu ◽  
...  
Keyword(s):  
Immunoglobulin G ◽  
Normal Subjects ◽  
Phospholipase A ◽  
Human Thyroid ◽  
Graves Disease ◽  
Washington Dc ◽  
Dependent Manner ◽  
Thyroid Cells ◽  
Dose Dependent ◽  
External Calcium

Atwa MA, Smallridge RC, Burch HB, Gist ID, Lu R, Abo-Hashem EM, El-Kannishy MH, Burman KD. Immunoglobulins from Graves' disease patients stimulate phospholipase A2 and C systems in FRTL-5 and human thyroid cells. Eur J Endocrinol 1996;135:322–7. ISSN 0804–4643 We have studied the effects of immunoglobulin G from Graves' disease patients on phospholipase A2 (PLA2) and C (PLC) systems in FRTL-5 and human thyroid cells. Immunoglobulin G (IgG) from Graves' disease patients stimulated arachidonic acid (AA) release in a time- and dose-dependent manner. In FRTL-5 thyroid cells, removal of external calcium had no significant effect on the IgG (20 μg/ml)-induced AA release in FRTL-5 thyroid cells. U-73122 (3 μmol/l), a PLC inhibitor, and quinacrine (100 μmol/l) but not U-26384 (5 μmol/l), PLA2 inhibitors, blocked the IgG-induced (20 μg/ml) AA release in FRTL-5 thyroid cells. Immunoglobulin G (100 μg/ml) also stimulated accumulation of inositol-1,4,5-triphosphate (IP3) in a time- and dose-dependent (20–300 μg/ml) manner in FRTL-5 cells. Immunoglobulin G from Graves' disease patients induced a significant increase of IP3 production (p = 0.01) compared to IgG from normal subjects. Removal of external calcium had no significant effect on the IgG-induced IP3 production. The PLC inhibitor U-73122 completely blocked IgG-induced IP3 production from FRTL-5 thyroid cells. Also, in human thyroid cells, IgG from Graves' disease patients induced a significant increase of AA release (p = 0.001) and IP3 production (p = 0.004) compared to the IgG from normal subjects. These data indicate that IgG from Graves' disease patients induced PLA2 activity that was PLC dependent, a pattern referred to as sequential activation. Our studies suggest that IgG from Graves' disease patients activates PLA2 and PLC systems in FRTL-5 and human thyroid cells. These signal transduction pathways could be involved in the pathogenesis of Graves' disease and future studies are warranted to investigate this area. Kenneth D Burman, Endocrine Section, Washington Hospital Center, 110 Irving St. NW, Washington, DC 20010, USA

Effects of recombinant bovine somatotrophin, insulin-like growth factor-I and insulin on bovine granulosa cell steroidogenesis in vitro

1994 ◽  
Vol 143 (1) ◽  
pp. 157-164 ◽  
Author(s):  
J G Gong ◽  
D McBride ◽  
T A Bramley ◽  
R Webb
Keyword(s):  
Granulosa Cell ◽  
Granulosa Cells ◽  
Dependent Manner ◽  
Serum Free ◽  
Factor I ◽  
Igf I ◽  
Serum Free Conditions ◽  
Dose Dependent ◽  
Bovine Somatotrophin ◽  
Cells Cultured

Abstract Our previous studies have demonstrated that physiological concentrations of metabolic hormones, including recombinant bovine somatotrophin (BST), insulin-like growth factor-I (IGF-I) and insulin, can significantly stimulate the proliferation of bovine granulosa cells cultured under serum-free conditions. In this study we investigated the effects of these factors on bovine granulosa cell steroidogenesis using the same culture system. Bovine granulosa cells were obtained from antral follicles classified into three size classes: small, <5 mm; medium-sized, 5–10 mm and large, >10 mm in diameter. Whilst not affecting steroidogenesis by granulosa cells from small and medium-sized follicles, BST (10–1000 ng/ml) stimulated the secretion of both oestradiol and progesterone by granulosa cells from large follicles in a dose-dependent manner. Insulin (1–1000 ng/ml) and IGF-I (10–1000 ng/ml) stimulated the secretion of oestradiol and progesterone by granulosa cells from all three size categories of follicles in a dose-dependent manner. FSH (200 ng/ml) alone increased progesterone secretion by granulosa cells from all three size classes of follicles, but had no effect on oestradiol secretion by granulosa cells. Both IGF-I (200 ng/ml) and insulin (30 ng/ml) acted in synergy with FSH (200 ng/ml) to stimulate steroidogenesis by granulosa cells from all three size categories of follicles, but no such interaction was observed between BST (50 ng/ml) and FSH (200 ng/ml). In conclusion, BST, IGF-I and insulin significantly influence the steroidogenic activity of bovine granulosa cells cultured under serum-free conditions. However, unlike their effects on cell proliferation, the minimal effective concentrations of these factors required to stimulate granulosa cell steroidogenesis were higher than those observed in our previous studies in vivo. Journal of Endocrinology (1994) 143, 157–164

scholarly journals High serum-free light chain levels and their rapid reduction in response to therapy define an aggressive multiple myeloma subtype with poor prognosis

Blood ◽  
2007 ◽  
Vol 110 (3) ◽  
pp. 827-832 ◽  
Author(s):  
Frits van Rhee ◽  
Vanessa Bolejack ◽  
Klaus Hollmig ◽  
Mauricio Pineda-Roman ◽  
Elias Anaissie ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Light Chain ◽  
Prognostic Significance ◽  
Complete Response ◽  
High Serum ◽  
Free Light Chain ◽  
Response To Therapy ◽  
Rapid Reduction ◽  
Serum Free ◽  
Serum Free Light Chain

Abstract Serum-free light chain (SFLC) levels are useful for diagnosing nonsecretory myeloma and monitoring response in light-chain–only disease, especially in the presence of renal failure. As part of a tandem autotransplantation trial for newly diagnosed multiple myeloma, SFLC levels were measured at baseline, within 7 days of starting the first cycle, and before both the second induction cycle and the first transplantation. SFLC baseline levels higher than 75 mg/dL (top tertile) identified 33% of 301 patients with higher near-complete response rate (n-CR) to induction therapy (37% vs 20%, P = .002) yet inferior 24-month overall survival (OS: 76% vs 91%, P < .001) and event-free survival (EFS: 73% vs 90%, P < .001), retaining independent prognostic significance for both EFS (HR = 2.40, P = .008) and OS (HR = 2.43, P = .016). Baseline SFLC higher than 75 mg/dL was associated with light-chain–only secretion (P < .001), creatinine level 176.8 μM (2 mg/dL) or higher (P < .001), beta-2-microglobulin 297.5 nM/L (3.5 mg/L) or higher (P < .001), lactate dehydrogenase 190 U/L or higher (P < .001), and bone marrow plasmacytosis higher than 30% (P = .003). Additional independent adverse implications were conferred by top-tertile SFLC reductions before cycle 2 (OS: HR = 2.97, P = .003; EFS: HR = 2.56, P = .003) and before transplantation (OS: HR = 3.31, P = .001; EFS: HR = 2.65, P = .003). Unlike baseline and follow-up analyses of serum and urine M-proteins, high SFLC levels at baseline—reflecting more aggressive disease—and steeper reductions after therapy identified patients with inferior survival.

Evaluation and Dilution Verification of the Optilite FreeliteTM Assay show discordant results at high serum free light chain concentrations

2019 ◽  
Vol 19 (10) ◽  
pp. e170-e171
Author(s):  
Terence A. Agbor ◽  
Michelle Parker ◽  
Barry Kyle ◽  
Irwindeep Sandhu ◽  
Chritopher Venner ◽  
...  
Keyword(s):  
Light Chain ◽  
High Serum ◽  
Free Light Chain ◽  
Serum Free ◽  
Serum Free Light Chain

Autoantibodies to thyroxin and triiodothyronine in the immunoglobulin G fraction of serum.

1988 ◽  
Vol 34 (12) ◽  
pp. 2561-2562 ◽  
Author(s):  
L Li Calzi ◽  
S Benvenga ◽  
S Battiato ◽  
F Santini ◽  
F Trimarchi
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Human Serum ◽  
Immunoglobulin G ◽  
Subacute Thyroiditis ◽  
Total Serum ◽  
Graves Disease ◽  
Carrier Proteins ◽  
Weak Binding ◽  
Idiopathic Myxedema

Abstract Thyroid hormone antibodies (THAbs)--i.e., antibodies to thyroxin (T4) and triiodothyronine (T3)--are detected rarely in human serum, where they are searched for, possibly because of a quantitatively minimal interaction between thyroid hormones (the haptens) and serum IgGs (the antibodies). The weak binding could result from these facts: (a) there are already six physiological carrier proteins for thyroid hormones; (b) THAbs usually account for a very small fraction of the total serum IgGs; (c) THAbs may have--as reported in the literature--a relatively low affinity. To ascertain whether THAbs could pass undetected in serum, we measured antibodies to T3 and T4 in both the serum and the corresponding IgG fraction of six normal persons and 45 patients with various thyroid diseases (Graves' disease, idiopathic myxedema, Hashimoto's thyroiditis, subacute thyroiditis, tumors), using radioimmunoprecipitation. The prevalence of antibodies to T4 was 0/51 in both the sera and the IgG fractions; the prevalence of antibodies to T3 was 1/51 in both materials. Because all of the sera that tested THAb negative were confirmed to be so in the THAb assay of the IgG fraction, we conclude that the prevalence of serum THAbs is not underestimated and that autoimmunization against thyroid hormones is really a rare phenomenon.

A new polymorphism in the type II deiodinase gene is associated with circulating thyroid hormone parameters

2005 ◽  
Vol 289 (1) ◽  
pp. E75-E81 ◽  
Author(s):  
Robin P. Peeters ◽  
Annewieke W. van den Beld ◽  
Hayat Attalki ◽  
Hans van Toor ◽  
Yolanda B. de Rijke ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Thyroid Hormone ◽  
Blood Donors ◽  
Muscle Size ◽  
Dependent Manner ◽  
Type Ii ◽  
Elderly Men ◽  
Similar Frequency ◽  
Dose Dependent ◽  
Tsh Levels

Type II deiodinase (D2) is important in the regulation of local thyroid hormone bioactivity in certain tissues. D2 in skeletal muscle may also play a role in serum triiodothyronine (T3) production. In this study, we identified a polymorphism in the 5′-UTR of the D2 gene (D2-ORFa-Gly3Asp). We investigated the association of D2-ORFa-Gly3Asp, and of the previously identified D2-Thr92Ala polymorphism, with serum iodothyronine levels. D2-ORFa-Gly3Asp was identified by sequencing the 5′-UTR of 15 randomly selected individuals. Genotypes for D2-ORFa-Gly3Asp were determined in 156 healthy blood donors (age 46.3 ± 12.2 yr) and 349 ambulant elderly men (age 77.7 ± 3.5 yr) and related to serum iodothyronine and TSH levels. D2-ORFa-Asp3had an allele frequency of 33.9% in blood bank donors and was associated with serum thyroxine (T4; Gly/Gly vs. Gly/Asp vs. Asp/Asp = 7.06 ± 0.14 vs. 6.74 ± 0.15 vs. 6.29 ± 0.27 μg/dl, P = 0.01), free T4(1.22 ± 0.02 vs. 1.16 ± 0.02 vs. 1.06 ± 0.04 ng/dl, P = 0.001), reverse T3( P = 0.01), and T3/T4ratio ( P = 0.002) in a dose-dependent manner, but not with serum T3( P = 0.59). In elderly men, D2-ORFa-Asp3had a similar frequency but was not associated with serum iodothyronine levels. This new polymorphism in the 5′-UTR of D2 is associated with iodothyronine levels in blood donors but not in elderly men. We hypothesize that this might be explained by the decline in skeletal muscle size during aging, resulting in a relative decrease in the contribution of D2 to serum T3production.

Renal Recovery Following Light Chain Removal by Extended Haemodialysis in a Patient with Cast Nephropathy.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5115-5115
Author(s):  
Colin A. Hutchison ◽  
Mark Cook ◽  
Arthur R. Bradwell ◽  
Paul Cockwell
Keyword(s):  
Renal Failure ◽  
Acute Renal Failure ◽  
Light Chain ◽  
Average Concentration ◽  
High Serum ◽  
Renal Recovery ◽  
Serum Free ◽  
Serum Free Light Chain ◽  
Cast Nephropathy ◽  
Average Serum

Abstract Cast nephropathy is the main cause of renal impairment in patients with multiple myeloma (MM). Serum free light chain (sFLC) removal by extended hemodialysis on a protein leaking membrane may aid renal recovery. A patient presenting with MM, high serum FLC concentrations and dialysis dependent acute renal failure was studied. A renal biopsy showed monoclonal kappa FLC cast nephropathy. He was dialysed for 2–8h on daily / alternate days using the Gambro HCO 1100 dialyser. sFLC were measured at frequent intervals in the serum and dialysate fluids. Albumin and urea concentrations were measure pre- and post-dialysis. Over 22 days the patient underwent 14 dialysis sessions with an average sFLC reduction of 38% (15.2–61.8%). A total of 16.5g of kappa was removed in the dialysate fluid with an average concentration of 18.3mg/L (3.3–27.3). Figure 1 demonstrates serum reductions in kappa concentrations pre- and post-dialysis and timing of chemotherapy. The average serum reductions were: albumin 2.1g/L, urea 56% and creatinine 44%. By day 22 the patient was independent of dialysis. Four months later renal function is stable with an eGFR of 35ml/min (Cockcroft-Gault). Further studies are needed to determine whether this method would benefit many patients with acute renal failure and light chain cast nephropathy. Figure Figure

scholarly journals Regulation of thyroid hormone activation via the liver X-receptor/retinoid X-receptor pathway

2010 ◽  
Vol 205 (2) ◽  
pp. 179-186 ◽  
Author(s):  
Marcelo A Christoffolete ◽  
Márton Doleschall ◽  
Péter Egri ◽  
Zsolt Liposits ◽  
Ann Marie Zavacki ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormone Receptor ◽  
Liver X Receptor ◽  
Retinoid X Receptor ◽  
Luciferase Reporter ◽  
Dependent Manner ◽  
Diet Induced Obesity ◽  
Ectopic Liver ◽  
Dose Dependent

Thyroid hormone receptor (TR) and liver X-receptor (LXR) are the master regulators of lipid metabolism. Remarkably, a mouse with a targeted deletion of both LXRα and LXRβ is resistant to western diet-induced obesity, and exhibits ectopic liver expression of the thyroid hormone activating type 2 deiodinase (D2). We hypothesized that LXR/retinoid X-receptor (RXR) signaling inhibits hepatic D2 expression, and studied this using a luciferase reporter containing the human DIO2 (hDIO2) promoter in HepG2 cells. Given that, in contrast to mammals, the chicken liver normally expresses D2, the chicken DIO2 (cDIO2) promoter was also studied. 22(R)-OH-cholesterol negatively regulated hDIO2 in a dose-dependent manner (100 μM, approximately twofold), while it failed to affect the cDIO2 promoter. Truncations in the hDIO2 promoter identified the region −901 to −584 bp as critical for negative regulation. We also investigated if 9-cis retinoic acid (9-cis RA), the ligand for the heterodimeric partner of TR and LXR, RXR, could regulate the hDIO2 promoter. Notably, 9-cis RA repressed the hDIO2 luciferase reporter (1 μM, approximately fourfold) in a dose-dependent manner, while coexpression of an inactive mutant RXR abolished this effect. However, it is unlikely that RXR homodimers mediate the repression of hDIO2 since mutagenesis of a DR-1 at −506 bp did not interfere with 9-cis RA-mediated repression. Our data indicate that hDIO2 transcription is negatively regulated by both 22(R)-OH-cholesterol and 9-cis RA, which is consistent with LXR/RXR involvement. In vivo, the inhibition of D2-mediated tri-iodothyronine (T3) production by cholesterol/9-cis RA could function as a feedback loop, given that T3 decreases hepatic cholesterol levels.

scholarly journals Development of a Luminescent Bioassay for Thyroid Stimulating Antibodies

1999 ◽  
Vol 84 (1) ◽  
pp. 374-377 ◽  
Author(s):  
C. Evans ◽  
N. G. Morgenthaler ◽  
S. Lee ◽  
D. H. Llewellyn ◽  
R. Clifton-Bligh ◽  
...  
Keyword(s):  
Reference Range ◽  
Thyroid Autoimmunity ◽  
Light Output ◽  
Fold Increase ◽  
Graves Disease ◽  
Dependent Manner ◽  
Multinodular Goitre ◽  
Thyroid Stimulating Antibodies ◽  
Luminescent Assay ◽  
Dose Dependent

The hyperthyroidism of Graves Disease (GD) is due to thyroid stimulating antibodies (TSAb) which are thyrotropin (TSH) agonists. They are detected routinely by measuring their ability to inhibit TSH binding to the receptor (TBII), which does not reflect their true biological activity. Current bioassays which measure cAMP by RIA, are not suitable for routine use. We have developed a luminescent bioassay for TSAb, by introducing a cAMP responsive luciferase construct into CHO cells stably expressing the human TSH receptor (TSHR). Clone lulu1 displays dose dependent TSH response detectable from 10 μU/ml and maximal at 10 mU/ml when a &gt;25 fold increase in light output is obtained. 34 euthyroid sera were tested to determine a reference range, with values &gt;1.5 relative light units (R.L.U.) being considered positive. An international TSAb standard responded in a dose dependent manner with 10 mIU/ml giving an R.L.U. of &gt;10. The assay was adapted to a 96 well format for automatic readout and 100 treated GD samples (50 TBII negative and 50 TBII positive) were tested, 73% being positive. In contrast only 4% of 79 control sera from individuals with Hashimoto’s, non-thyroid autoimmunity or multinodular goitre produced R.L.U. &gt;1.5. When 44 of the GD sera were compared in a traditional salt-free bioassay, 61% were positive compared with 75% in the new luminescent assay. In conclusion, we have developed a luminescent bioassay for TSAb, using unfractionated serum which is capable of high throughput suitable for routine use.

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