Thyroglobulin IgG ELISA
The Immunolab Thyroglobulin IgG Antibody ELISA Test Kit has been designed for the detection and the quantitative determination of specific IgG antibodies against Thyroglobulin in serum and plasma. Further applications in other body fluids are possible and can be requested from the Technical Service of Immunolab.
In various diseases of the thyroid, autoantibodies against thyroid antigens are found in the serum. The most important antigens are:
– Thyroglobulin (TG)
– Thyroid peroxidase (TPO) (formerly known as microsomal antigen)
– TSH-Receptor
The determination of these autoantibodies has a diagnostic and a predictive value. Women express thyroid autoimmunity more frequently than men. This tendency is even more obvious at the postmenopausal period. These women with significant autoantibody titer against thyroid microsomal antigen or thyroid peroxidase and against thyroglobulin are prone to develop chronic thyroiditis resulting in thyroid atrophy and hypothyroidism. It is important to screen all mothers-tobe for thyroid autoimmunity and to determine carefully the titers of thyroid autoantibodies and thyroid function in the postpartum period. In younger patients, the combination of a firm goitre with high titers of anti-TG and anti-TPO autoantibodies is highly suggestive of Hashimito’s disease, a chronic lymphomonocytic thyroiditis. Thyroid functions of these goitres will progressively fail, leading to hypothyroidism. In Graves Basedow’s disease, significant anti-TG and anti-TPO autoantibody titers indicate the coexistence of chronic thyroiditis in association with the toxic goitre. This should be considered in the follow-up of the patients, and specially after radical treatments such as partial thyroidectomy or radio-iodine therapy. Indeed, hyperthyroid patients with high titers of anti-TG and anti-TPO autoantibodies exhibit a greater susceptibility to develop hypothyroidism in the long term after such treatments. The determination of anti-TSH receptor autoantibody titer is also very important in the evaluation of a patient suffering from Graves Basedow’s disease. In general practice, the detection of thyroid autoimmunity may signify that the patient is at risk of other autoimmune diseases including pernicious anaemia, Sjögren’s and Sicca Syndromes, adrenal insufficiency and hypoparathyroidism.
The Immunolab Thyroglobulin IgG antibody test kit is based on the principle of the enzyme immunoassay (EIA). Thyroglobulin antigen is bound on the surface of the microtiter strips. Diluted patient serum or ready-to-use Calibrators are pipetted into the wells of the microtiter plate. A binding between the IgG antibodies of the serum and the immobilized Thyroglobulin antigen takes place. After a one hour incubation at room temperature, the plate is rinsed with diluted wash solution, in order to remove unbound material. Then ready-to-use anti-human-IgG peroxidase conjugate is added and incubated for 30 minutes. After a further washing step, the substrate (TMB) solution is pipetted and incubated for 20 minutes, inducing the development of a blue dye in the wells. The color development is terminated by the addition of a stop solution, which changes the color from blue to yellow. The resulting dye is measured spectrophotometrically at the wavelength of 450 nm. The concentration of the IgG antibodies is directly proportional to the intensity of the color.
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