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Updated: Jul 27, 2026
07:01
An Orthotopic Mouse Model of Anaplastic Thyroid Carcinoma
Published on: April 17, 2013
The alpha-galactosyl epitope on mammalian thyroid cells
A Thall1, J Etienne-Decerf, R J Winand
1Department of Laboratory Medicine, University of California, San Francisco.
Acta Endocrinologica
|June 1, 1991
Summary
Natural anti-galactosyl IgG antibodies target alpha-galactosyl epitopes found on nonprimate mammal and New World monkey thyroid cells. These epitopes are absent in human and Old World monkey thyroids due to lower alpha 1-3 galactosyltransferase activity.
Area of Science:
- Immunology
- Glycobiology
- Endocrinology
Background:
- Autoimmune thyroid disorders are associated with increased natural anti-alpha-galactosyl IgG antibody titers.
- Alpha-galactosyl epitopes (Gal alpha 1-3Gal beta 1-4GlcNAc-R) are present on mammalian cell membranes.
Purpose of the Study:
- To investigate the distribution of alpha-galactosyl epitopes on mammalian thyroid cell membranes.
- To correlate epitope presence with alpha 1-3 galactosyltransferase activity and potential anti-thyroid reactivity.
Main Methods:
- Radioimmunoassay (RIA) was employed to quantify alpha-galactosyl epitopes.
- Thyroid cell membranes from various species were analyzed.
Main Results:
- Alpha-galactosyl epitopes were detected on thyroid cell membranes of nonprimate mammals and New World monkeys.
- These epitopes were absent in Old World monkeys and humans.
- Absence in humans and Old World monkeys correlated with reduced alpha 1-3 galactosyltransferase activity.
Conclusions:
- The distribution of alpha-galactosyl epitopes varies across mammalian species.
- Reduced alpha 1-3 galactosyltransferase activity explains the absence of these epitopes in human thyroids.
- Natural anti-alpha-galactosyl IgG antibodies may contribute to anti-thyroid reactivity in human sera.
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