Rabbit antibodies against two different extracellular domains of human thyrotropin receptor possess thyroid stimulating activities.
We have produced rabbit antibodies against synthetic peptides corresponding to the mid-region (amino acid residues 172-202, C peptide) and to the unique segment near the transmembrane region (amino acid residues 341-370, P peptide) in the extracellular component of the human thyrotropin (TSH) receptor and evaluated their biological activities. Both anti-C peptide antibodies raised in two rabbits showed strong thyroid stimulating activities (TSAb) (4127% and 2548%). Anti-P peptide antibodies raised in two rabbits were also strongly positive for TSAb activities (359% and 3468%). However, none of these antibodies had TSH-binding inhibitor immunoglobulin (TBII) activities. These results suggest that the domains responsible for TSAb are likely to span the entire extracellular component of the TSH receptor.
Third Department of Internal Medicine, University of Yamanashi Medical School, Japan.
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Endo
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Ohmori
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Ikeda
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Kotani
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Onaya
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology*; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology; D011817:Rabbits / Q000276:immunology; D011989:Receptors, Thyrotropin / Q000276:immunology*; D013961:Thyroid Gland / Q000276:immunology*
D000906:Antibodies; D010455:Peptides; D011989:Receptors, Thyrotropin