Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0028754 (obesity)
 124,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The binding of chicken thyroglobulin-coated chicken red blood cells by splenic, thymic, and bursal lymphoid cells was analysed in Obese strain (OS) chickens with spontaneous autoimmune thyroiditis and normal white Leghorn controls aged 1 week to 2.5 yr. Chicken erythrocytes coated with pneumococcal polysaccharide SIIII served as controls. The specificity of thyroglobulin-rosette-forming cells was verified by inhibition experiments. OS chickens showed significantly higher counts of thyroglobulin-rosette-forming cells in the spleen and thymus as compared to normal controls while no such difference was found for SII-rosette-forming cells. The values obtained with bursal lymphoid cells were in the same range in both OS and normal white Leghorn birds. The appearance of thyroglobulin-rosette-forming cells and their peak values clearly preceded the maximum frequency and severity of thyroiditis and the peak of the thyroglobulin antibody curve. It is concluded that the presence of thyroglobulin rosette-forming cells is a prerequisite for the future development of spontaneous autoimmune thyroiditis in the OS. Inhibition studies with specific turkey anti-chicken bursa and thymus cell sera revealed the B cell nature of active thyroglobulin-rosette-forming cells and suggested that passive rosette-forming cells were of T cell origin.
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PMID:Thyroglobulin-binding lymphoid cells in obese strain (OS) chickens. 23 98

Homozygeous nu/nu mice do not develop experimental autoimmune thyroiditis and circulating thyroglobulin autoantibodies after two immunizations with murine thyroid extract and fortified complete Freund's adjuvant. However, heterozygeous nu/+ mice are perfectly apt for the induction of both thyroiditis and thyroglobulin autoantibodies. These results provide further evidence for the assumption that the development of experimentally induced autoimmune thyroiditis depends on the presence of T-cells as opposed to the spontaneously occurring autoimmune thyroiditis in Obese strain (OS) chickens which is mediated by B-effector cells. The present data further show that thyroglobulin is a T-dependent antigen in the mouse.
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PMID:No development of experimental autoimmune thyroiditis in nude mice. 30 59

F1-hybrids of Obese strain (OS) chickens, afflicted with spontaneous autoimmune thyroiditis (SAT), and normal, inbred CB chickens, do not develop severe thyroiditis. About 50% of these crosses show circulating autoantibodies to thyroglobulin (TgAAb), but the thyroid glands are only slightly infiltrated, suggesting that the target organ is not susceptible to autoimmune attack. In the present study we show that despite this mild infiltration TgAAb are only synthesized by lymphoid cells within the thyroid gland. Furthermore, we demonstrate that immunization with chicken thyroglobulin (Tg) in complete Freund's adjuvant causes severe experimental autoimmune thyroiditis (EAT) in F1(OSxCB) hybrids.
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PMID:Target organ susceptibility and autoantibody production in an animal model of spontaneous autoimmune thyroiditis. 139 97

Interleukin 2 (IL-2) is a lymphokine that may disrupt immunological self-tolerance. While being incapable of interfering with intrathymic or peripheral clonal deletion, IL-2 may overcome functional antigen unresponsiveness in anergic T lymphocytes. Anergy of T helper cells of the inflammatory phenotype implies selective silencing of the transcription of the IL-2 gene and thus precludes autocrine IL-2/IL-2 receptor (IL-2R) mediated growth, as well as delivery of help to other T cells or B lymphocytes. Thus, IL-2 serves as a servomodulator regulating post-deletional self-tolerance. IL-2-producing and IL-2-receptive cells are present in a variety of autoimmune lesions, including spontaneous autoimmune thyroiditis developing in the Obese strain (OS) of chickens, in Hashimoto's struma lymphomatosa, and in Graves' disease. Whereas the OS is characterized by a hyperinducibility of the IL-2/IL-2R system that predisposes to the development of severe thyroid infiltration, the state of the IL-2/IL-R system in circulating lymphocytes of patients developing thyroid autoimmunity, or at risk of doing so, remains to be defined. The most frequent autoimmune side-effect of IL-2 treatment concerns the thyroid gland. IL-2 induces a lymphoid thyroiditis leading to primary hypothyroidism, especially in those patients that have pre-treatment antithyroid autoantibodies. The hypothesis is extrapolated that IL-2 induces autoimmune disease in those patients that bear undeleted thyroid-specific T cells, and in which the lack of manifest thyroiditis relies upon peripheral, post-deletional tolerance.
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PMID:The role of interleukin 2 in the development of autoimmune thyroiditis. 148 52

We studied the clinical features, laboratory and thyroid functions and thyrotropin (TSH)-receptor and thyroid-stimulation antibodies in 21 patients with atrophic auto-immune thyroiditis (AAT) and 48 patients with goitrous auto-immune thyroiditis (GAT) of childhood onset. The clinical features of patient with AAT were cessation of growth and obesity, while asymptomatic enlargement of the thyroid gland was the sole symptom in most patients with GAT. Although the ages at diagnosis were comparable in both groups, the estimated ages at onset were much lower in patients with AAT than in those with GAT. Patients with AAT exhibited more severe hypothyroidism when evaluated by serum thyroxine (T4), tri-iodothyronine (T3), TSH, cholesterol levels and basal metabolic rates. The 24 h 123I-thyroidal uptake was significantly lower in patients with AAT than in those with GAT. None of the 19 patients with AAT possessed TSH-binding inhibitor immunoglobulins (TBII). On the other hand, 3 of the 32 GAT patients tested, possessed weak to potent TBII activities. Three TBII-positive patients with GAT also possessed thyroid-stimulation blocking antibodies. These findings suggest that: 1. Pathogenesis of AAT in children whose onset of hypothyroidism was before puberty is not due to TSH-receptor blocking antibodies, which are often found in patients with AAT of postpubertal onset. 2. AAT in children is considered not to be due to the later stage of GAT. 3. Some patients with GAT possessed TSH-receptor blocking antibodies. The aetiology and pathogenesis of AAT in children have yet to be elucidated.
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PMID:Comparison of atrophic and goitrous auto-immune thyroiditis in children: clinical, laboratory and TSH-receptor antibody studies. 234 50

Dietary iodine has been shown to be important in the induction of thyroiditis in susceptible chicken strains although the underlying mechanism remains unknown. Iodine may exert its effects through the formation of reactive oxidative radicals which would cause thyroidal injury and initiate infiltration. We have tested this hypothesis by examining the ability of butylated hydroxyanisole (BHA), ethoxyquin, and other antioxidants to prevent thyroiditis in Obese strain (OS) chickens, a strain that develops severe disease by 4 weeks of age. BHA, when administered from hatching until death at 5 weeks of age, reduced thyroidal infiltration and serum levels of antibodies binding thyroglobulin, T3, T4. Similar effects were observed with the antioxidant ethoxyquin. Weaker antioxidants such as vitamins C and E and beta-carotene had only slight or negligible effects on these parameters. BHA reduced thyroiditis in OS chicks killed at 3 and 5 weeks of age, but not at 8 weeks. When BHA treatment was initiated after the development of severe disease, it did not reduce thyroglobulin antibody levels. To determine the mechanism by which BHA reduces thyroiditis, studies were performed to assess the effect of BHA on thyroid function and on the immune responses to exogenous antigens. BHA had no effect on thyroid function in normal strain chickens since thyroidal radioiodine uptake and organification and serum T3 and T4 levels were unaffected. BHA did not alter immune responses to exogenous antigens such as sheep red blood cells or Brucella abortus in OS chickens. In summary, potent antioxidant drugs delayed the onset of thyroiditis when treatment was initiated before the onset of disease, suggesting that reactive oxygen intermediates are involved in the early stages of pathogenesis. However, the site of action remains unknown since they had no detectable effects on thyroid function or general immune responses.
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PMID:Antioxidants delay the onset of thyroiditis in obese strain chickens. 240 Dec 27

The characteristics of thyroglobulin (Tg) autoantibodies in Obese strain (OS) chickens with thyroiditis have been defined and compared with those of polyclonal antibodies to chicken Tg produced by immunizing normal chickens and a rabbit, and with mouse monoclonal antibodies (MoAb) to chicken Tg. Chicken Tg autoantibodies (aAb), when tested against Tg from 24 species all showed specificity for chicken Tg which ranged from absolute to limited although in most instances cross-reactions with Tgs of other species were either absent or at a low level. Antibodies to chicken Tg produced by immunization showed a similar limited range of cross-reactions. Four of five chTg-MoAbs were specific for chicken Tg and the fifth was almost so. In competitive experiments, the polyclonal rabbit antibody could fully inhibit binding of all chicken Tg-aAb to chicken Tg but not vice versa. It was inferred that polyclonal rabbit Tg antiserum includes antibodies to all the epitopes seen by chicken Tg-aAb and many more besides. In similar experiments with four chicken Tg-MoAbs, the binding of one chicken Tg-aAb was unaffected, and three other patterns of inhibitions were defined. The binding to chicken Tg of a fifth chicken Tg-MoAb was enhanced rather than inhibited by chicken Tg-aAb. Some but not all chicken Tg-aAb preparations could differentiate between Tgs containing different amounts of thyroxine. We conclude that the autoantibodies to Tg in OS chickens are directed in the main against determinants unique to the species. Not all the species-specific determinants are involved in the autoimmune response but the number of epitopes involved is at least four. In these respects the immune response to Tg in OS chickens resembles that in autoimmune thyroid disease in humans. The conformation of chicken Tg may be affected by combination with antibody or by the content of thyroid hormone.
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PMID:Selective autoimmune response to the chicken-specific structures of thyroglobulin in Obese strain chickens. 276 75

A management programme is described for a small colony of Obese strain (OS) chickens afflicted with spontaneous hereditary thyroiditis. Animals of this White Leghorn line are used as an animal model for Hashimoto's thyroiditis of man to study possible mechanisms of autoimmunity in general and organ-specific autoimmune diseases in particular. Due to the severe mononuclear cell infiltration of the thyroid glands, OS chickens show symptoms of hypothyroidism, including small body size, subcutaneous and abdominal fat deposits, long silky feathers, small combs and wattles, cold sensitivity, low fertility and poor hatchability. Successful breeding of this line, especially in a small population, can therefore be done only if rigid precautions are taken in aspects of animal care. The selection of breeding stock, the principal requirements for adequate housing and food, the artificial insemination procedure, and recommendations for collecting and incubating chicken eggs are reported in detail. Precautions necessary during the incubation of fertilized eggs, and fertility and hatchability are reported. During the hatching period several specific features must be considered. The important role of staff involved in a small chicken breeding unit is emphasized.
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PMID:Housing, breeding and selecting chickens of the Obese strain (OS) with spontaneous autoimmune thyroiditis. 281 Dec 74

A monoclonal antibody (INN-CH-16) was prepared which reacts with a cell surface antigen termed chicken activated T lymphocyte antigen. This antigen is expressed on antigen- or mitogen-activated T lymphocytes and is not present on nonstimulated lymphocytes. It has an apparent molecular mass of 48-50 kDa under reducing conditions. The value of this antibody for the immunohistochemical characterization of infiltrating cells in the thyroid glands from Obese strain chickens with spontaneous thyroiditis is demonstrated.
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PMID:A monoclonal antibody reacting with a membrane determinant expressed on activated chicken T lymphocytes. 302 1

Various degrees of persistent or paroxysmal paresis involving only the hindlimbs or all four limbs were observed in 3 dogs with hypothyroidism and lymphocytic thyroiditis. Clinical features included lethargy, obesity, alopecia, insidious and progressive paresis, hypotonia, and slow segmental reflexes in 2 dogs. Obesity, alopecia, paroxysmal paresis, and behavior change were observed in the third dog. Laboratory tests indicated that thyroid function was less than normal in all 3 dogs. Abnormal electromyographic potentials and slow motor nerve conduction velocities were found in each dog. Muscle biopsy specimen abnormalities included selective type-II myofiber atrophy in all dogs, whereas one dog had angular atrophy of type-I and type-II myofibers indicative of denervation. A substance that stained with para-aminosalicylic acid was observed within vacuoles of type-I myofibers in one dog. Lymphocytic thyroiditis characterized by lymphocytic infiltration of excised thyroid glands was observed in all dogs.
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PMID:Neuromuscular abnormalities associated with hypothyroidism and lymphocytic thyroiditis in three dogs. 355 92


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