title: Epitope recognition in HLA-DR3 transgenic mice immunized to TSH-R protein or peptides.
abstract: Development of Graves' disease is related to HLA-DR3. The extracellular domain (ECD) of human TSH receptor (hTSH-R) is a crucial antigen in Graves' disease. hTSH-R peptide 37 (amino acids 78-94) is an important immunogenic peptide in DR3 transgenic mice immunized to hTSH-R. This study examined the epitope recognition in DR3 transgenic mice immunized to hTSH-R protein and evaluated the ability of a mutant hTSH-R peptide to attenuate the immunogenicity of hTSH-R peptide 37. DR3 transgenic mice were immunized to recombinant hTSH-R-ECD protein or peptides. A mutant hTSH-R 37 peptide (ISRIYVSIDATLSQLES: 37 m), in which DR3 binding motif position 5 was mutated V>A, and position 8 Q>S, was synthesized. 37 m should bind to HLA-DR3 but not bind T cell receptors. DR3 transgenic mice were immunized to hTSH-R 37 and 37 m. Mice immunized to hTSH-R-ECD protein developed strong anti-hTSH-R antibody, and antisera reacted strongly with hTSH-R peptides 1-5 (20-94), 21 (258-277), 41 (283-297), 36 (376-389), and 31 (399-418). Strikingly, antisera raised to hTSH-R peptide 37 bound to hTSH-R peptides 1-7 (20-112), 10 (132-50), 33 (137-150), 41, 23 (286-305), 24 (301-320), 36, and 31 as well as to hTSH-R-ECD protein. Both antibody titers to hTSH-R 37 and reaction of splenocytes to hTSH-R 37 were significantly reduced in mice immunized to hTSH-R 37 plus 37 m, compared with mice immunized to hTSH-R 37 alone. The ability of immunization to a single peptide to induce antibodies that bind hTSH-R-ECD protein, and multiple unrelated peptides, is a unique observation. Immunogenic reaction to hTSH-R peptide 37 was partially suppressed by 37 m, and this may contribute to immunotherapy of autoimmune thyroid disease.
authors.affiliation: Department of Cellular and Molecular Biology, University of Rhode Island, Kingston, Rhode Island 02881, USA. inaba@wakayama-med.ac.jp
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Inaba
authors.forename: Leonard
authors.initials: L
authors.lastname: Moise
authors.forename: William
authors.initials: W
authors.lastname: Martin
authors.forename: Anne S
authors.initials: AS
authors.lastname: De Groot
authors.forename: Joe
authors.initials: J
authors.lastname: Desrosiers
authors.forename: Ryan
authors.initials: R
authors.lastname: Tassone
authors.forename: George
authors.initials: G
authors.lastname: Buchman
authors.forename: Takashi
authors.initials: T
authors.lastname: Akamizu
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: De Groot
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000378:metabolism; D001665:Binding Sites / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology* / Q000378:metabolism; D005260:Female; D006111:Graves Disease / Q000276:immunology / Q000378:metabolism / Q000628:therapy; D015803:HLA-DR3 Antigen / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007106:Immune Sera / Q000276:immunology / Q000378:metabolism; D007114:Immunization; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009154:Mutation; D010446:Peptide Fragments / Q000276:immunology* / Q000378:metabolism; D011485:Protein Binding; D011948:Receptors, Antigen, T-Cell / Q000276:immunology / Q000378:metabolism; D011989:Receptors, Thyrotropin / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology / Q000378:metabolism; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000378:metabolism
chemical_list: D000906:Antibodies; D000939:Epitopes; D015803:HLA-DR3 Antigen; D007106:Immune Sera; D010446:Peptide Fragments; D011948:Receptors, Antigen, T-Cell; D011989:Receptors, Thyrotropin; D011994:Recombinant Proteins