Thyroid Peroxidase Antibodies | Thyroglobulin Antibodies
Thyroid Peroxidase Antibodies
Products
|
Article No.
|
No. of tests
|
ImmunoCAP Thyroid Peroxidase |
14-4508-35 |
3x16 tests |
Varelisa TPO Antibodies |
123 96 |
96 tests |
Antigens
Thyroid Peroxidase (TPO) has been characterized as an integral membrane hemoprotein (MW around 100 kDa), which catalyzes the iodination of thyroglobulin (TG), as well as the coupling of two di-iodothyrosine residues in the TG molecule to form thyroxine. The actual nature of the "microsomal antigen" remained unknown for nearly three decades, until in 1985 when Portmann et al. could show, that the microsomal antigen is identical to TPO. The sensitivity and specificity of TPO antibodies assays rely heavily on the purity and quality fo the test antigen and in particular on the absence of TG contaminant.
The Varelisa TPO Antibodies assay and the ImmunoCAP Thyroid Peroxidase use human recombinant TPO, produced in eukaryotic cells (Baculovirus/Sf9 system).
Disease association, antibody prevalence and specificity
- Hashimoto Thyroiditis (91-99 %)
- Graves' Disease (71-97 %)
- Primary Myxedema (40-70 %)
- Post-partum Thyroiditis (60 %)
- Subacute Thyroiditis (de Quervain) (very rare)
- Endocrine Orbitopathy (47 %)
- Simple Goiter (25 %)
- Thyroid Cancer (5 %)
- My occur in organ-specific autoimmune diseases, including Pernicious Dnemia, Addison's Disease, type I Diabetes Mellitus, Polyglandular Endocrine Failure Syndromes etc.
- Healthy individuals (5-15 %, higher in elderly, but mostly in low titers)
Information about the diseases
New assays have sensitivities and specificities of >95 %. Negative tests can virtually exclude a diagnosis of thyroiditis.
Disease activity
Quantitatively, there is a tendency for individuals with higher autoantibody levels to be more susceptible to hypothyroidism.
When is the measurement recommended?
- Suspicion of Thyroiditis
- Pregnancy in women with familial history of thyroid or autoimmune complications
Antibody isotype
IgG
References
Rapoport B, McLachlan SM (1996)
| McLachlan SM, Rapoport B (1995)
| Kraiem Z (1998)
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Thyroglobulin Antibodies
Product
|
Article No.
|
No. of tests
|
Varelisa TG Antibodies |
121 96 |
96 tests |
ImmunoCAP Thyroglobulin |
14-4507-35 |
3x16 tests |
Antigens
Thyroglobulin (TG) is a large 670 kDa globular glycoprotein composed of two identical disulfide-linked subunits. The majority of thyroid iodine is associated with this prohormone which plays an important role in the biosynthesis of the thyroid homones T3 and T4. About 75% of the total protein content of the thyroid follicle consists of thyroglobulin. Due to the large TG content of the thyroid gland, a good antigen quality and purity can be achieved using conventional purification techniques.
The Varelisa TG Antibodies assay and the ImmunoCAP Thyroglobulin are coated with thyroglobulin purified from human thyroid glands.
Disease association, antibody prevalence and specificity
- Hashimoto Thyroiditis (60-85 %)
- Graves' Disease (30-80 %)
- Primary Myxedema (20-30 %)
- Post-partum Thyroiditis (30 %)
- Subacute Thyroiditis (de Quervain) (very rare)
- Endocrine Orbitopathy (24 %)
- Simple Goiter (4 %)
- Thyroid Cancers (2-15 %)
- Pernicious Anemia (27 %)
- Addison's Disease (28 %)
- Diabetes Mellitus (20 %)
- Healthy Individuals (4-8 %, higher in elderly, but mostly in lower titers)
Autoantibodies to TG and TPO provide a valuable exclusionary test in patients with thyroid disease, because over 98% of thyroiditis patients have autoantibodies to either or both of these antigens. Negative tests can virtually exclude a diagnosis of thyroiditis.
Disease activity
Primary risk factor to future autoimmune thyroid dysfunction. A change in TG antibody levels may provide useful information in postoperative patients with differentiated thyroid carcinoma; an elevation of these antibodies could indicate recurrence or metastases.
When is the measurement recommended?
- Suspicion of Thyroiditis
- Differnatioted Thyroid Carcinoma after operation
Antibody isotype
IgG
References
Burek CL, Rose NR (1996)
| Kraiem Z (1998)
| Fisher DA, Pandian MR, Carlton E (1987)
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