Sensitization and desensitization of human thyroid cells in culture: effects of thyrotrophin and thyroid-stimulating immunoglobulin

1988 ◽  
Vol 119 (2) ◽  
pp. 341-349 ◽  
Author(s):  
Z. Kraiem ◽  
R. Alkobi ◽  
O. Sadeh
Keyword(s):  
Secretory Activity ◽  
Time Lapse ◽  
Human Thyroid ◽  
Thyroid Cells ◽  
Subsequent Exposure ◽  
Heterologous Desensitization ◽  
High Doses ◽  
Culture Effects

ABSTRACT Using an in-vitro system of cultured human thyroid cells and cyclic AMP (cAMP) accumulation as an index of cell stimulation, we compared TSH and thyroid-stimulating immunoglobulin (TSI) with regard to thyrocyte sensitization and desensitization. The smallest dose of TSH (0·05 mU/ml) capable of stimulating thyroid cells was the same as the minimum dose required to induce desensitization upon subsequent rechallenge with the hormone. In contrast, about 30-fold higher doses of TSI were needed to cause cell refractoriness compared with doses capable of eliciting stimulation. Moreover, significant stimulation of the thyroid with TSI was apparent much later than with TSH. A longer time-lapse was also necessary for TSI to induce densensitization. Likewise, thyrocytes recovered more slowly from TSI compared with TSH desensitization. Although at high doses TSI induced homologous desensitization, at lower doses the antibody, unlike TSH, potentiated the cAMP response to subsequent exposure to the antibody. The stimulatory doses of TSI were in the range usually encountered in active Graves' disease, which may explain why prolonged TSI in vivo sustains a hyperthyroid condition. In addition, we found that under conditions in which TSH leads to desensitization of the cAMP response, the thyroid cells maintained their responsiveness in terms of triiodothyronine secretory activity. Pre-exposure of human thyrocytes to TSI induced heterologous desensitization towards the TSH-stimulated cAMP response. Moreover, addition of the antibody to maximally desensitizing doses of TSH decreased cell sensitivity to the hormone even further. In sharp contrast, preincubation of cells with TSH, or TSH plus TSI, potentiated by four- and twofold respectively the cAMP response to subsequent challenge with TSI. Taken together, the data reveal marked differences between the action of TSH and TSI, and raise interesting questions concerning the mechanism whereby TSH potentiates the cAMP response to TSI. J. Endocr. (1988) 119, 341–349

In Vitro Culture of Human Thyroid Cells: Preliminary Findings on the Role of the Pathological Condition of the Donors

1997 ◽  
Vol 25 (2) ◽  
pp. 153-160
Author(s):  
Francesca Mattioli ◽  
Marianna Angiola ◽  
Laura Fazzuoli ◽  
Francesco Razzetta ◽  
Antonietta Martelli
Keyword(s):  
Pathological Condition ◽  
Primary Cultures ◽  
S Phase ◽  
Human Thyroid ◽  
Thyroid Cells ◽  
Toxicological Studies ◽  
Predictive Indicator

Although primary cultures of human thyroid cells are used for endocrinological and toxicological studies, until now no attention has been paid toward verifying whether the hormonal conditions to which the gland was exposed in vivo prior to surgery could influence in vitro responses. Our findings suggest that the hormonal situation in vivo cannot be used as a predictive indicator of triiodothyronine and thyroxine release and/or S-phase frequency in vitro, either with or without the addition of bovine thyrotropin.

scholarly journals Acrylamide does not induce tumorigenesis or major defects in mice in vivo

2008 ◽  
Vol 198 (2) ◽  
pp. 301-307 ◽  
Author(s):  
Ling Jin ◽  
Vanessa Chico-Galdo ◽  
Claude Massart ◽  
Christine Gervy ◽  
Viviane De Maertelaere ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Chronic Administration ◽  
Serum Levels ◽  
Human Thyroid ◽  
Thyroid Cell ◽  
Thyroid Cells ◽  
Hormone Synthesis ◽  
Rat Thyroid

Chronic administration of acrylamide has been shown to induce thyroid tumors in rat. In vitro acrylamide also causes DNA damage, as demonstrated by the comet assay, in various types of cells including human thyroid cells and lymphocytes, as well as rat thyroid cell lines. In this work, mice were administered acrylamide in their drinking water in doses comparable with those used in rats, i.e., around 3–4 mg/kg per day for mice treated 2, 6, and 8 months. Some of the mice were also treated with thyroxine (T4) to depress the activity of the thyroid. Others were treated with methimazole that inhibits thyroid hormone synthesis and consequently secretion and thus induces TSH secretion and thyroid activation. These moderate treatments were shown to have their known effect on the thyroid (e.g. thyroid hormone and thyrotropin serum levels, thyroid gland morphology…). Besides, T4 induced an important polydipsia and degenerative hypertrophy of adrenal medulla. Acrylamide exerted various discrete effects and at high doses caused peripheral neuropathy, as demonstrated by hind-leg paralysis. However, it did not induce thyroid tumorigenesis. These results show that the thyroid tumorigenic effects of acrylamide are not observed in another rodent species, the mouse, and suggest the necessity of an epidemiological study in human to conclude on a public health policy.

IN-VITRO STUDIES OF NORMAL HUMAN THYROID CELLS: RESPONSES TO THYROTROPHIN AND DIBUTYRYL CYCLIC AMP

1977 ◽  
Vol 72 (1) ◽  
pp. 87-96 ◽  
Author(s):  
S. P. BIDEY ◽  
P. MARSDEN ◽  
J. ANDERSON ◽  
C. G. McKERRON ◽  
H. BERRY
Keyword(s):  
Cyclic Amp ◽  
Thyroid Tissue ◽  
Three Dimensional ◽  
Human Thyroid ◽  
Dibutyryl Cyclic Amp ◽  
Iodide Uptake ◽  
Thyroid Cells ◽  
Normal Human

SUMMARY Follicular cells isolated from normal human thyroid tissue have been cultured for up to 140 h with bovine thyrotrophin (TSH) or dibutyryl cyclic AMP (DBcAMP). Both compounds induced marked reorganization of the cells into three-dimensional follicular structures, whilst non-supplemented cells assumed a monolayer form. Cultures treated initially with TSH or DBcAMP showed a greater iodide uptake capacity, in comparison with unsupplemented cultures, in which iodide uptake was markedly diminished after 24 h. The release of tri-iodothyronine (T3) and thyroxine (T4) into the medium was determined by radioimmunoassay. Both TSH- and DBcAMP-treated cells showed a significant increase in iodothyronine output compared with unsupplemented control cells. In contrast to the 'classical' TSH-induced depression of the T4:T3 ratio in vivo, an increase in the ratio was observed for both TSH- and DBcAMP-supplemented cells in vitro. The ratio was also significantly greater after TSH than after DBcAMP, and possible implications of this finding are discussed.

scholarly journals Reexpression of blood group ABH antigens on the surface of human thyroid cells in culture.

1982 ◽  
Vol 94 (1) ◽  
pp. 193-200 ◽  
Author(s):  
E L Khoury
Keyword(s):  
Cell Surface ◽  
Blood Group ◽  
Enzymatic Digestion ◽  
Cell Suspensions ◽  
Human Thyroid ◽  
Blood Group Antigens ◽  
Thyroid Cells ◽  
Blood Group Abh

Using indirect immunofluorescence (IFL) on viable human thyroid cultures, it has been shown that, although adult follicular cells do not express blood group ABH antigens in vivo, they invariably reexpress the corresponding antigens on the cell surface when cultured in monolayers, even for very short periods. The absence of blood group antigens on noncultured thyroid cells was confirmed by negative IFL on cell suspensions obtained after enzymatic digestion of the glands, whereas these antigens were readily demonstrable on cell suspensions obtained by trypsinization of established monolayers. The quantitative expression of ABH antigens on individual thyroid cells was variable and the cell-surface IFL pattern due to binding of blood group isoantibodies was different from that given by organ-specific thyroid autoantibodies on viable cultures. Reexpression of blood group antigens by cultured thyroid cells could not be related to the secretor status of the donors, the presence of a particular source of serum in the culture medium or cell division in vitro. After 2-3 wk in culture, thyroid cells became morphologically dedifferentiated and no longer displayed blood group antigens, though they still expressed cell-surface beta 2-microglobulin. Fibroblasts present in the primary thyroid cultures were invariably negative for ABH antigens. These results demonstrate that the surface antigenic repertoire of cultured human cells is not necessarily identical to that present on the same cells in vivo. Furthermore, the possibility that blood group natural isoantibodies bind to the cell surface must be taken into account in experiments in which cultured thyroid cells are exposed to human sera.

Local factors regulating growth and function of human thyroid cells in vitro and in vivo

2003 ◽  
Vol 213 (1) ◽  
pp. 47-58 ◽  
Author(s):  
Margaret C. Eggo ◽  
Virginia M. Quiney ◽  
Spencer Campbell
Keyword(s):  
Human Thyroid ◽  
Thyroid Cells ◽  
Local Factors ◽  
And Function

scholarly journals Thyroid follicular cells secrete plasminogen activators and can form angiostatin from plasminogen

2002 ◽  
Vol 173 (3) ◽  
pp. 475-481 ◽  
Author(s):  
JD Ramsden ◽  
S Yarram ◽  
E Mathews ◽  
JC Watkinson ◽  
MC Eggo
Keyword(s):  
Conditioned Medium ◽  
Angiogenesis Inhibitors ◽  
Plasminogen Activators ◽  
Tissue Type ◽  
Matrix Metalloproteinase 2 ◽  
Human Thyroid ◽  
Angiogenic Growth Factors ◽  
Thyroid Cells

Angiostatin, a 38 kDa fragment of plasminogen, potently inhibits the growth of blood vessels. Angiostatin is generated from plasminogen by urokinase-type (uPA) and tissue-type (tPA) plasminogen activators in the presence of free sulphydryl donors. Angiogenesis inhibitors may be important in regulating angiogenesis in developing goitre. We have examined angiostatin formation in human primary thyrocyte cultures and a rat thyrocyte cell line (FRTL-5). We found that human thyroid cells in culture secrete plasminogen activators (both tPA and uPA) as well as matrix metalloproteinase 2 into the medium. When human thyrocyte conditioned medium was incubated with plasminogen (10 microg/ml) and N-acetylcysteine (100 microM) for 24 h, a 38 kDa fragment of plasminogen, which is consistent with angiostatin, was generated. The appearance of the 38 kDa fragment was increased by agents that increase cAMP (forskolin and 8 BrcAMP). FRTL-5 cells, which do not secrete uPA or tPA, did not generate angiostatin. Thyroid cells produce several angiogenic growth factors, and human thyrocyte conditioned medium stimulated growth of endothelial cells. When the conditioned medium was incubated with plasminogen and N-acetylcysteine, this stimulatory effect was lost, consistent with the production of a growth inhibitory factor. We conclude that thyroid cells can produce angiostatin from plasminogen in vitro, and this may play a role in vivo in limiting goitre size.

scholarly journals Development of an In Vitro Human Thyroid Microtissue Model for Chemical Screening

2019 ◽  
Vol 174 (1) ◽  
pp. 63-78 ◽  
Author(s):  
Chad Deisenroth ◽  
Valerie Y Soldatow ◽  
Jermaine Ford ◽  
Wendy Stewart ◽  
Cassandra Brinkman ◽  
...  
Keyword(s):  
High Throughput Screening ◽  
Screening Program ◽  
3D Culture ◽  
Hazard Identification ◽  
Human Thyroid ◽  
Screening Assay ◽  
Thyroid Cells ◽  
Chemical Screening

Abstract Thyroid hormones (TH) are essential for regulating a number of diverse physiological processes required for normal growth, development, and metabolism. The US EPA Endocrine Disruptor Screening Program (EDSP) has identified several molecular thyroid targets relevant to hormone synthesis dynamics that have been adapted to high-throughput screening (HTS) assays to rapidly evaluate the ToxCast/Tox21 chemical inventories for potential thyroid disrupting chemicals (TDCs). The uncertainty surrounding the specificity of active chemicals identified in these screens and the relevance to phenotypic effects on in vivo human TH synthesis are notable data gaps for hazard identification of TDCs. The objective of this study was to develop a medium-throughput organotypic screening assay comprised of reconstructed human thyroid microtissues to quantitatively evaluate the disruptive effects of chemicals on TH production and secretion. Primary human thyroid cells procured from qualified euthyroid donors were analyzed for retention of NK2 homeobox 1 (NKX2-1), Keratin 7 (KRT7), and Thyroglobulin (TG) protein expression by high-content image analysis to verify enrichment of follicular epithelial cells. A direct comparison of 2-dimensional (2D) and 3-dimensional (3D) 96-well culture formats was employed to characterize the morphology, differential gene expression, TG production, and TH synthesis over the course of 20 days. The results indicate that modeling human thyroid cells in the 3D format was sufficient to restore TH synthesis not observed in the 2D culture format. Inhibition of TH synthesis in an optimized 3D culture format was demonstrated with reference chemicals for key molecular targets within the thyroid gland. Implementation of the assay may prove useful for interpreting phenotypic effects of candidate TDCs identified by HTS efforts currently underway in the EDSP.

scholarly journals In vitro and in vivo regulation of thyrotropin receptor mRNA levels in dog and human thyroid cells.

1992 ◽  
Vol 267 (5) ◽  
pp. 3000-3007
Author(s):  
C Maenhaut ◽  
G Brabant ◽  
G Vassart ◽  
J.E. Dumont
Keyword(s):  
Human Thyroid ◽  
Mrna Levels ◽  
Thyrotropin Receptor ◽  
Thyroid Cells ◽  
Receptor Mrna

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

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