anti-Tg
Enzyme immunoassay for the quantitative determination of autoantibodies to thyreoglobulin (Tg) in serum and plasma
Procedure
Sample volume 50 µl; Total assay time approx. 45 min
Characteristics
CE marked quick and easy to use kit
*EDTA, citrate and heparin plasma samples may be used
No interference was observed: haemoglobin < 500 mg/dl; bilrubin < 20 mg/dl and intralipid < 3,000 md/dl
Suitable for automatic systems
Calibrator range 35 – 5000 units/ml (standardised to NIBSC 65/093)
Lower detection limit: 9.8 U/ml (2 standard deviation)
In some diseases of the thyroid, serum autoantibodies against some thyroid antigens are found. The most important antigens are:
• Thyroglobulin (Tg)
• Thyroid peroxidase (TPO), formerly known as microsomal antigen
• TSH-Receptor
Measurement of these autoantibodies is of considerable value in the diagnosis of autoimmune thyroid diseases (Hashimoto-thyroiditis, primary myxedema, hyperthyroidism, asymptomatic autoimmune thyroiditis) and the anti-Tg-ELISA kit provides a convenient method of quantitating Tg autoantibodies in patients’ serum or plasma samples.
The assay is based on an easy to use and flexible strip well system employing wells coated with highly purified thyroglobulin. Autoantibody binding to the Tg coated wells is detected using Protein A conjugated to alkaline phosphatase as marker and p-nitrophenyl phosphate as substrate. Quantification of unknowns is achieved by comparing the enzymatic activity of unknowns with a response curve prepared by using known standards (NIBSC65/093).
The same diluted sample can be used for both anti-Tg-ELISA and antiTPO-ELISA.
- B. Rees Smith (2001); Thyroid Autoantibodies Scand J Clin Lab Invest 2001 61 (suppl 235): pp. 45-52.
- P. Burne et al. (2005); “Point of care assays for autoantibodies to thyroid peroxidase
and thyroglobulin” Thyroid 2005 15: 1005-1010