Peptide scanning for thyrotropin receptor T-cell epitopes in mice vaccinated with naked DNA.
Vaccinating mice with DNA encoding the thyrotropin receptor (TSHR), the major autoantigen in Graves' disease, induces memory T cells that secrete interferon-gamma (IFN-gamma) in response to TSHR antigen. We used a panel of 29 synthetic TSHR peptides encompassing the ectodomain and three extracellular loops to identify T-cell epitopes after TSHR-DNA vaccination of BALB/c, NOD.H-2h4, and AKR/N mice. These strains were chosen because of their previous use in animal models of thyroid autoimmunity. In initial studies, challenge of splenocytes with TSHR protein induced IFN-gamma and tumor necrosis factor-alpha (TNF-alpha) production in all three strains of mice. BALB/c mice recognized three peptides, all in the TSHR A subunit. These peptides differed from the four peptides recognized by nonobese diabetic (NOD mice NOD H-2h4). Three of the latter were also in the A subunit. The fourth was within the intervening C peptide region excised on TSHR cleavage into A and B subunits. Because of high and erratic responses in AKR/N mice, their TSHR T-cell epitopes could not be determined. In summary, we report that TSHR DNA vaccination of BALB/c and NOD.H-2h4 mice, with different major histocompatibility complex (MHC) class II genes (I-Ad and I-Ak, respectively), recognize restricted, nonoverlapping TSHR T-cell epitopes, nearly all in the TSHR A subunit.
Pichurin
Pavel
P
Autoimmune Disease Unit, Cedars Sinai Research Institute and UCLA School of Medicine, Los Angeles, California, USA.
Schwarz-Lauer
Lise
L
Braley-Mullen
Helen
H
Paras
Charmaine
C
Pichurina
Oxana
O
Morris
John C
JC
Rapoport
Basil
B
McLachlan
Sandra M
SM
D000595:Amino Acid Sequence; D000818:Animals; D000918:Antibody Specificity; D001323:Autoantibodies / Q000097:blood; D018984:Epitopes, T-Lymphocyte / Q000737:chemistry* / Q000276:immunology; D006111:Graves Disease / Q000276:immunology; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D051379:Mice; D008806:Mice, Inbred AKR; D008807:Mice, Inbred BALB C; D016688:Mice, Inbred NOD; D008969:Molecular Sequence Data; D011989:Receptors, Thyrotropin / Q000737:chemistry* / Q000276:immunology*; D020539:Sequence Analysis, Protein; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D013966:Thyroiditis / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D019444:Vaccines, DNA / Q000494:pharmacology*
D001323:Autoantibodies; D018984:Epitopes, T-Lymphocyte; D007376:Interleukin-2; D011989:Receptors, Thyrotropin; D014409:Tumor Necrosis Factor-alpha; D019444:Vaccines, DNA; D007371:Interferon-gamma