A synthetic oligopeptide derived from human thyrotropin receptor sequence binds to Graves' immunoglobulin and inhibits thyroid stimulating antibody activity but lacks interactions with TSH.
An 11-residue oligopeptide, P-195, was synthesized to match human thyrotropin (TSH) receptor structure from No. 333 to 343 of amino acid sequence. Preincubation of 5 Graves' IgGs with P-195 up to 10 micrograms resulted in dose-dependent reductions of thyroid stimulating antibody (TSAb) activity. [125I] labeled P-195 was found to bind Graves' IgG. The bound radioactivity correlated significantly with their TSAb activity (N = 25, r = 0.587, p less than 0.01). A peptide having a completely reverse sequence as P-195 did not show such biological activity. The peptide did not affect TSH and thyrotropin binding inhibitor immunoglobulin (TBII) on their receptor binding nor biological activities. P-195 was concluded to have a part of TSAb binding sites.
Department of Laboratory Medicine, Kyoto University School of Medicine, Japan.
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Mori
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Sugawa
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Piraphatdist
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Inoue
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Enomoto
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Imura
D000595:Amino Acid Sequence; D000818:Animals; D001323:Autoantibodies / Q000276:immunology*; D001666:Binding Sites, Antibody; D001798:Blood Proteins / Q000276:immunology / Q000378:metabolism; D002462:Cell Membrane / Q000276:immunology; D000242:Cyclic AMP / Q000096:biosynthesis; D006111:Graves Disease / Q000097:blood / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D018828:Immunoglobulins, Thyroid-Stimulating; D007700:Kinetics; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000138:chemical synthesis / Q000276:immunology* / Q000494:pharmacology; D011989:Receptors, Thyrotropin / Q000276:immunology*; D012016:Reference Values; D013552:Swine; D013961:Thyroid Gland / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D013972:Thyrotropin / Q000097:blood
D001323:Autoantibodies; D001798:Blood Proteins; D007074:Immunoglobulin G; D018828:Immunoglobulins, Thyroid-Stimulating; D009842:Oligopeptides; D011989:Receptors, Thyrotropin; D013972:Thyrotropin; D000242:Cyclic AMP