Abstract |
Anti- TSH receptor antibodies (TSH-R Ab), which have been detected in the serum of some patients with primary myxedema, are themselves considered to induce hypothyroidism. These are termed blocking-type TSH-R Ab (TSH-R BAb), because they inhibit adenylate cyclase stimulation by TSH on thyrocytes or nonthyroidal cells transfected with TSH-R complementary DNA. We prepared monoclonal TSH-R BAb and characterized them. Peripheral lymphocytes from three patients with primary hypothyroidism and potent TSH-R BAb were transformed by Epstein-Barr virus, and the culture supernatants were screened by TSH binding inhibitor immunoglobulin (TBII) assay. Twenty positive and 7 negative lymphocyte clones were obtained; their monoclonality was confirmed by Southern blot analysis, using an immunoglobulin (Ig) JH probe. These monoclonal antibodies were then tested for TSH-R BAb activity. TSH-R BAb activity ranged from 24.1-58.5% (normal range, < 24%) in all 20 TBII-positive clones and in 2 of 7 TBII-negative clones. An enzyme-linked immunosorbent assay showed that the Ig isotypes of these clones with TBII and/or TSH-R BAb activity were IgG in 8 and IgM in 14. Another enzyme-linked immunosorbent assay and Southern blot analysis of the light chains revealed that 13 clones had kappa-chains, whereas the light chains could not be determined in the other 9 clones. To summarize, 1) we obtained 22 clones that produced monoclonal TSH-R BAb, including 8 IgG-type clones. 2) The clones exhibited dominant usage of the kappa-chain. 3) Although all TBII clones had TSH-R BAb activity, their TBII and TSH-R BAb activities were not significantly correlated, and two TSH-R BAb clones did not show TBII activity.
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Authors | J Okuda, T Akamizu, H Sugawa, F Matsuda, L Hua, T Mori |
Journal | The Journal of clinical endocrinology and metabolism
(J Clin Endocrinol Metab)
Vol. 79
Issue 6
Pg. 1600-4
(Dec 1994)
ISSN: 0021-972X [Print] United States |
PMID | 7989462
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Antibodies, Monoclonal
- Autoantibodies
- Immunoglobulin G
- Immunoglobulin M
- Receptors, Thyrotropin
- DNA
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Topics |
- Animals
- Antibodies, Monoclonal
(blood, genetics)
- Autoantibodies
(blood, genetics)
- Blotting, Southern
- CHO Cells
- Clone Cells
- Cricetinae
- DNA
(analysis)
- Gene Rearrangement, B-Lymphocyte, Heavy Chain
- Gene Rearrangement, B-Lymphocyte, Light Chain
- Humans
- Hypothyroidism
(immunology)
- Immunoglobulin G
(blood)
- Immunoglobulin M
(blood)
- Myxedema
(immunology)
- Receptors, Thyrotropin
(genetics, immunology)
- T-Lymphocytes
(immunology)
- Transfection
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