Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2014 Mar;24(3):411-23.
doi: 10.1089/thy.2013.0119. Epub 2013 Dec 13.

Thyrotropin isoforms: implications for thyrotropin analysis and clinical practice

Joshua M Estrada  1 , Danielle Soldin, Timothy M Buckey, Kenneth D Burman, Offie P Soldin
Affiliations
Review

Thyrotropin isoforms: implications for thyrotropin analysis and clinical practice

Joshua M Estrada et al. Thyroid. 2014 Mar.

Abstract

Serum thyrotropin (TSH) is considered the single most sensitive and specific measure of thyroid function in the general population owing to its negative logarithmic association with free triiodothyronine and free thyroxine concentrations. It is therefore often the test of choice for screening, diagnosis, and monitoring of primary hypothyroidism. Serum TSH concentrations can be analyzed quantitatively using third-generation immunoassays, whereas its bioactivity can be measured by TSH activity assays in cell culture. Theoretically, if serum TSH concentrations are directly related to TSH activity, the two tests should yield comparable results. However, on occasion, the results are discordant, with serum concentrations being higher than TSH biological activity. This review focuses on the dissociation between the clinical state and serum TSH concentrations and addresses clinically important aspects of TSH analysis.

PubMed Disclaimer

Figures

<b>FIG. 1.</b>
FIG. 1.
TSH α- and β-subunits. A normal human TSH molecule contains an α-subunit with two oligosaccharide chains (located at Asn-52 and Asn-78) and a β-subunit with one oligosaccharide chain (located at Asn-23). Each subunit contains a terminal sialic acid and a sulfate residue that confer TSH binding and biological activity. Asn, asparagine; TSH, thyrotropin.
<b>FIG. 2.</b>
FIG. 2.
Suggested structure of the human TSH molecule with two major subunits that confer biological and immunological activity. Each subunit contains glycan branches (designated by the arrows) whose terminal ends can alter TSH binding to its receptors and prevent proper renal clearance. [Structure is modified from (88).]
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Grossmann M, Weintraub BD, Szkudlinski MW.1997Novel insights into the molecular mechanisms of human thyrotropin action: structural, physiological, and therapeutic implications for the glycoprotein hormone family. Endocr Rev 18:476–501 - PubMed
    1. Weintraub BD, Stannard BS, Magner JA, Ronin C, Taylor T, Joshi L, Constant RB, Menezes-Ferreira MM, Petrick P, Gesundheit N.1985Glycosylation and posttranslational processing of thyroid-stimulating hormone: clinical implications. Recent Prog Horm Res 41:577–606 - PubMed
    1. Magner JA.1990Thyroid-stimulating hormone: biosynthesis, cell biology, and bioactivity. Endocr Rev 11:354–385 - PubMed
    1. Shupnik MA, Ridgway EC, Chin WW.1989Molecular biology of thyrotropin. Endocr Rev 10:459–475 - PubMed
    1. Pierce JG, Parsons TF.1981Glycoprotein hormones: structure and function. Annu Rev Biochem 50:465–495 - PubMed

Publication types