Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This chapter describes four murine models of autoimmune diseases: two related to autoimmune myocarditis and two related to autoimmune thyroiditis. The first model, Coxsackie virus B3 (CB3)-induced myocarditis, results in the development of acute myocarditis in susceptible as well as resistant mouse strains, whereas chronic myocarditis develops only in genetically susceptible mice. CB3-induced myocarditis closely resembles the course of human myocarditis, which is believed to be initiated by viral infection. Mouse cardiac myosin heavy chain has been identified as the major antigen associated with the late chronic phase of viral myocarditis. The second model is cardiac myosin-induced experimental autoimmune myocarditis (EAM) and, in a modification, cardiac alpha-myosin heavy chain peptide-induced myocarditis. In the EAM model, cardiac myosin or the relevant peptide in Freund's complete adjuvant (FCA) is injected subcutaneously into mice. The immune response, the histological changes, and the genetic susceptibility seen in EAM are similar to those of CB3-induced myocarditis. The third model is experimental autoimmune thyroiditis (EAT). EAT can be induced in genetically susceptible strains of mice by immunization with mouse thyroglobulin in FCA or lipopolysaccharide. Mice susceptible to EAT have the H-2A(k), H-2A(s), or H-2A(q) alleles. We describe here a standard technique for the induction of EAT; it was developed in our laboratory and is widely used as a model for studying Hashimoto's thyroiditis. The fourth model presented in this chapter is that of spontaneous autoimmune thyroiditis in NOD.H2h4 mice. These mice express the H-2A(k) allele on an NOD genetic background and develop spontaneous thyroiditis, which is exacerbated with dietary iodine.
Methods Mol Med 2004
PMID:Animal models for autoimmune myocarditis and autoimmune thyroiditis. 1528 86

Chimeric RET/PTC (rearranged in transformation/papillary thyroid carcinoma) oncoproteins are constitutively active tyrosine kinases found in thyroid papillary carcinoma and nonneoplastic Hashimoto's thyroiditis. Although several proteins have been identified to be substrates of RET/PTC kinases, the pathogenic roles played by RET/PTC in malignant and benign thyroid diseases and the molecular mechanisms that are involved are not fully understood. We found that RET/PTC expression phosphorylates the Y701 residue of STAT1, a type II interferon (IFN)-responsive protein. RET/PTC-mediated signal transducer and activator of transcription 1 (STAT1) phosphorylation requires RET/PTC kinase activity to be intact but other tyrosine kinases, such as Janus kinases or c-Src, are not involved. RET/PTC-induced STAT1 transcriptional activation was not inhibited by suppressor of cytokine signaling-1 or -3, or protein inhibitors of activated STAT3 [(protein inhibitor of activated STAT (PIAS3)], but PIAS1 strongly repressed the RET/PTC-induced transcriptional activity of STAT1. RET/PTC-induced STAT1 activation caused IFN regulatory factor-1 expression. We found that STAT1 and IFN regulatory factor-1 cooperated to significantly increase transcription from type IV IFN-gamma responsive promoters of class II transactivator genes. Significantly, cells stably expressing RET/PTC expressed class II transactivator and showed enhanced de novo membrane expression of major histocompatibility complex (MHC) class II proteins. Furthermore, RET/PTC1-bearing papillary thyroid carcinoma cells strongly expressed MHC class II (human leukocyte-associated antigen-DR alpha) genes, whereas the surrounding normal tissues did not. Thus, RET/PTC is able to phosphorylate and activate STAT1. This may lead to enhanced MHC class II expression, which may explain why the tissues surrounding RET/PTC-positive cancers are infiltrated with lymphocytes. Such immune response-promoting activity of RET/PTC may also relate to the development of Hashimoto's thyroiditis.
Mol Endocrinol 2004 Nov
PMID:Regulation of signal transducer and activator of transcription 1 (STAT1) and STAT1-dependent genes by RET/PTC (rearranged in transformation/papillary thyroid carcinoma) oncogenic tyrosine kinases. 1529 6

An experimental murine model of Graves' disease was used to produce monoclonal antibodies (mAbs) with thyroid stimulating activity. Two of these, IRI-SAb2 and IRI-SAb3, showed particularly high potency (in the low nanomolar range) and efficacy. IRI-SAb2 behaved as a full agonist of the human TSH receptor (TSHr), even when tested in physiological salt concentrations. Both IRI-SAb2 and IRI-SAb3 were displaced from the TSHr by autoantibodies from patients with Graves' disease or harboring thyroid-blocking antibodies, but not from control subjects or patients with Hashimoto thyroiditis. The epitopes of IRI-SAb2 and IRI-SAb3 were precisely mapped, at the amino acid level, to the amino-terminal portion of the concave portion of the horseshoe structure of TSHr ectodomain. They overlap closely with each other and, surprisingly, with the epitope of a mAb with blocking activity. When injected iv in mice, both mAbs caused biological and histological signs of hyperthyroidism. Unexpectedly, they also triggered an inflammatory response in the thyroid glands. Delineation of the conformational epitopes of these stimulating antibodies opens the way to the identification of the molecular mechanisms implicated in the activation of the TSHr.
Mol Endocrinol 2004 Dec
PMID:Delineation of the discontinuous-conformational epitope of a monoclonal antibody displaying full in vitro and in vivo thyrotropin activity. 1531 53

The CD45 antigen is a haemopoietic cell specific tyrosine phosphatase essential for antigen receptor mediated signalling in lymphocytes. Expression of different patterns of alternatively spliced CD45 isoforms is associated with distinct functions. We recently identified a polymorphism in exon 6 (A138G) of the gene encoding CD45 (PTPRC) that results in altered CD45 splicing. The 138G allele is present at a high frequency among Japanese (23.7%), with 5.1% individuals homozygous for the G allele. In this study we show that the A138G polymorphism is the cause of altered CD45 isoform expression, promoting splicing towards low molecular weight CD45 isoforms. We further report that the frequency of A138G heterozygotes is significantly reduced in number in cohorts of patients with autoimmune Graves' disease or hepatitis B infection, whereas G138G homozygotes are absent from a cohort of Hashimoto's thyroiditis patients. We also show that 138G individuals exhibit altered cytokine production in vitro and an increased proportion of memory T cells. These data suggest that the 138G variant allele strongly influences these diseases by modulation of immune mechanisms and may have achieved its high frequency as a result of a natural selection probably related to pathogen resistance.
Hum Mol Genet 2004 Oct 15
PMID:Disease associations and altered immune function in CD45 138G variant carriers. 1533 87

Fas-mediated apoptosis has been proposed to play an important role in the pathogenesis of Hashimoto's thyroiditis. Normal thyroid cells are resistant to Fas-mediated apoptosis in vitro but can be sensitized by the unique combination of interferon-gamma and IL-1beta cytokines. We sought to examine the mechanism of this sensitization and apoptosis signaling in primary human thyroid cells. Without the addition of cytokines, agonist anti-Fas antibody treatment of the thyroid cells resulted in the cleavage of proximal caspases, but this did not lead to the activation of caspase 7 and caspase 3. Apoptosis associated with the cleavage of caspases 7, 3, and Bid, and the activation of mitochondria in response to anti-Fas antibody occurred only after cytokine pretreatment. Cell surface expression of Fas, the cytoplasmic concentrations of procaspases 7, 8, and 10, and the proapoptotic molecule Bid were markedly enhanced by the presence of the cytokines. In contrast, P44/p42 MAPK (Erk) appeared to provide protection from Fas-mediated apoptosis because an MAPK kinase inhibitor (U0126) sensitized thyroid cells to anti-Fas antibody. In conclusion, Fas signaling is blocked in normal thyroid cells at a point after the activation of proximal caspases. Interferon-gamma/IL-1beta pretreatment sensitizes human thyroid cells to Fas-mediated apoptosis in a complex manner that overcomes this blockade through increased expression of cell surface Fas receptor, increases in proapoptotic molecules that result in mitochondrial activation, and late caspase cleavage. This process involves Bcl-2 family proteins and appears to be compatible with type II apoptosis regulation.
Mol Endocrinol 2005 Mar
PMID:Induction and regulation of Fas-mediated apoptosis in human thyroid epithelial cells. 1556 45

Toll-like receptors (TLRs) initiate an innate immune response. TLR3 on dendritic cells recognize double-stranded (ds) RNA and then signal increases in cytokines and recognition molecules important for immune cell interactions. In this report, we demonstrate TLR3 mRNA and protein are expressed on Fisher rat thyroid cell line-5 (FRTL-5) thyroid cells and are functional because incubating cells with polyinosine-polycytidylic acid causes 1) transcriptional activation of both the nuclear factor kappaB (NF-kappaB)/Elk1 and interferon (IFN) regulatory factor-3/IFN-beta signal paths, 2) posttranscriptional activation of NF-kappaB and ERK1/2, and 3) increased IFN-beta mRNA. TLR3 can be overexpressed, along with dsRNA-dependent protein kinase, major histocompatibility complex-I or II, and IFN regulatory factor-1, by transfecting dsRNA into the cells, infection with Influenza A virus, or incubation with IFN-beta, but not by incubation with dsRNA or IFNgamma, or by dsDNA transfection. A methimazole (MMI) derivative, phenylmethimazole, to a significantly greater degree than MMI, prevents overexpression by inhibiting increased transcriptional activation of IRF-3 and of IFN-stimulated response elements, phosphorylation of signal transducers and activation of transcription (STAT-1), but not NF-kappaB activation. TLR3 can be functionally overexpressed in cultured human thyrocytes by dsRNA transfection or IFN-beta treatment. Immunohistochemical studies show that TLR3 protein is overexpressed in human thyrocytes surrounded by immune cells in 100% of patients with Hashimoto's thyroiditis examined, but not in normal or Graves' thyrocytes. We conclude that functional TLR3 are present on thyrocytes; TLR3 downstream signals can be overexpressed by pathogen-related stimuli; overexpression can be reversed by phenylmethimazole to a significantly greater extent than MMI by inhibiting only the IFN regulatory factor-3/IFN-beta/signal transducers and activation of transcription arm of the TLR3 signal system; and TLR3 overexpression can induce an innate immune response in thyrocytes, which may be important in the pathogenesis of Hashimoto's thyroiditis and in the immune cell infiltrates.
Mol Endocrinol 2005 May
PMID:Thyrocytes express a functional toll-like receptor 3: overexpression can be induced by viral infection and reversed by phenylmethimazole and is associated with Hashimoto's autoimmune thyroiditis. 1566 32

To investigate the expression of apoptosis-related protein (Fas, FasL, and Bcl-2) in the pathogenesis of autoimmune thyroid disorders (ATDs), immunohistochemical staining was performed on 20 Hashimoto's thyroiditis (HT), 20 Graves' disease (GD), and 20 thyroid follicular adenoma (TFA, as control). All the cases expressed Fas, mainly on the cell surface and cytoplasm. FasL was found in 17 cases of the TFA. Bcl-2 was detected in 15 cases of HT, 19 of GD and 17 of TFA. In TFA, a moderate Fas expression and a minimal or no FasL expression was detected on follicular cells. In HT, the follicles adjacent to infiltrating lymphocytes showed increased levels of Fas and FasL expression. A weaker staining of Fas and FasL was exhibited on infiltrating lymphocytes than on thyrocytes. In a comparison of GD with HT, thyrocytes and lymphocytes showed similar Fas staining, but for FasL the staining was rather weaker in HT. The expression of Bcl-2 was nearly identical in GD and TFA, but much weaker on the follicular cells in vicinity of lymphocytes and on the lymphocytes located in germinal centers of HT tissues. The expression of Fas, FasL, Bcl-2 in Hashimoto's thyroiditis and Graves' disease were almost same. FasL strong expression and Bcl-2 weak expression on the follicles in HT may induce apoptosis. These results provided evidence for expression of Fas, FasL and Bcl-2 in the pathogenesis of autoimmune thyroid disease. The lymphocytes seem not to be directly engaged in the process via their own FasL, but they may provide some cytokines that, in turn, upregulate Fas and/or FasL expression to induce apoptosis.
Cell Mol Immunol 2004 Jun
PMID:Analysis of the expression of Fas, FasL and Bcl-2 in the pathogenesis of autoimmune thyroid disorders. 1621 72

The thyroid gland is an endocrine organ composed of stable cells. It is well known that regenerative capacity of the thyroid tissue is minimal. Various degrees of morphologic alterations do occur in chronic lymphocytic thyroiditis (CLT), including Hashimoto's thyroiditis. Eighty-five CLT cases were analyzed for these morphologic alterations. Small, irregular, atrophic or hyperplastic thyroid follicles were seen adjacent to the lymphocytic infiltration. There was nuclear enlargement, loss of nuclear polarity in thyrocytes and intrafollicular thyrocyte proliferation in these follicles. We thought that the morphologic alterations in involved follicles could be due to regenerative hyperplasia with increased proliferative activity and basement membrane abnormalities. To examine this hypothesis we investigated Ki-67 and laminin immunoreactivity in the involved follicles adjacent to lymphocytic infiltration areas. The uninvolved follicles were used as controls. Immunopositivity of Ki-67 in involved follicles was significantly higher than that in uninvolved follicles (2.97% +/- 2.16 versus 0.83% +/- 1.63, P < 0.001). Laminin immunostaining indicated the destruction or irregular distribution of basement membrane in involved follicles. We conclude that the increased cell proliferation activity and basement membrane abnormalities in the follicles with morphologic changes adjacent to CLT occur in conjunction with regenerative hyperplasia.
Appl Immunohistochem Mol Morphol 2005 Dec
PMID:Regenerative hyperplasia of follicular epithelium in chronic lymphocytic thyroiditis. 1628 Jun 65

To investigate the expression and distribution of S-100 protein and CD 83 in the thyroid tissues of autoimmune thyroid diseases (ATDs), and to study the role of the dendritic cells in the pathogenesis of ATDs, immunohistochemical staining was used on pathological tissues of 20 patients with Hashimoto's thyroiditis (HT) and 20 patients with Graves' disease (GD) to check the expression and distribution of S-100 protein and CD 83. Compared with control group (20 cases of thyroid follicular adenoma, TFA), the higher expressions of S-100 in HT (139.38+/-5.92 vs 59.47+/-11.69) and GD (119.42+/-14.48 vs 59.47+/-11.69) were observed respectively (p<0.001). The increased positive expressions of CD 83 which is known as a marker of mature and activated DCs in HT (22.58+/-13.96 vs 5.19+/-8.08) and GD (29.92 +/-14.43 vs 5.19+/-8.08) were also found respectively (p<0.001). Serum TPO antibody (TPO-Ab, 67.3+/-11.6%) and Tg antibody (Tg-Ab, 59.8+/-10.1%) in HT were higher than those in GD (28.4+/-5.7%, 23.1+/-4.9%) and TFA (6.1+/-3.4%, 7.2 +/-4.6%) (p<0.01). Serum TR-Ab in GD (16.3+/-5.6 U/L) was higher than those in HT (4.8+/- 2.3 U/L) and TFA (2.5+/-1.2 U/L) (p<0.01). Our findings suggest that the high expression of DCs' markers may be related to the pathogenesis of HT and GD. The upregulation of both the number and the matured functions of DCs, may lead to present more antigens and to produce more auto-antibodies (such as Tg-Ab and TPO-Ab in HT, TR-Ab in GD), which may be involved in pathogenesis of the autoimmune thyroid diseases.
Cell Mol Immunol 2004 Oct
PMID:The expression and distribution of S-100 protein and CD 83 in thyroid tissues of autoimmune thyroid diseases. 1628 98

Aim-To evaluate the expression of ribosomal cistrons in human thyroid epithelial cells (TECs) of patients with Grave's disease, Hashimoto's thyroiditis and benign and malignant tumours of the thyroid gland.Methods-TEC nucleoli were investigated in fine needle biopsy specimens from 10 controls, 39 patients with Grave's disease, 15 with Hashimoto's thyroiditis, 56 with benign, and 15 with malignant tumours of the thyroid. A one step silver staining method was applied. In most cases serum concentrations of thyroxine and triiodothyronine as well as goitre size were determined. In every case 100 TECs were evaluated for the mean numbers of nucleoli and for the average number of argyrophilic nucleolar organiser regions (AgNORs) per nucleus.Results-NORs were activated in all patients, but not in controls. The numbers of AgNORs in patients with Grave's disease were closely correlated with thyroxine or triiodothyronine, or both, concentrations and with the size of the thyroid. In patients with Hashimoto's thyroiditis about 30% of TECs nucleoli did not contain AgNORs, whereas others were heavily impregnated with silver. Compared with controls and benign tumours, the nucleoli of carcinomatous TECs were larger and irregular in shape. The mean number of AgNORs per nucleus in malignant cells was higher than that in their benign counterparts.Conclusions-The mechanism by which NORs are activated in TECs varies depending on the type of lesion. The higher AgNOR score in TECs from malignant tumours can be used to distinguish them from their benign counterparts.
Clin Mol Pathol 1996 Aug
PMID:Interphase ribosomal RNA cistron staining in thyroid epithelial cells in Grave's disease, Hashimoto's thyroiditis and benign and malignant tumours of the thyroid gland. 1669 83


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