title: Evidence of a combined cytotoxic thyroglobulin and thyroperoxidase epitope-specific cellular immunity in Hashimoto's thyroiditis.
abstract: BACKGROUND
  Hashimoto's thyroiditis (HT) is a common autoimmune disease leading to thyroid destruction due to lymphocytic infiltration. Only rare data are available regarding the recognition of specific cellular antigens, e.g. of thyroperoxidase (TPO) and thyroglobulin (Tg).
  
  
  OBJECTIVE
  The aim of this study was to quantify and characterize TPO- and Tg-epitope-specific CD8-positive T cells of HT patients.
  
  
  METHODS
  Six different human leukocyte antigen (HLA)-A2 restricted, TPO- or Tg-specific tetramers were synthesized and used for measuring CD8-positive T cells in HT patients and controls.
  
  
  RESULTS
  The frequency of peripheral TPO- and Tg-specific CD8-positive T cells was significantly higher in HLA-A2-positive HT patients (2.8 ± 9.5%) compared with HLA-A2-negative HT patients (0.5 ± 0.7%), HLA-A2-positive nonautoimmune goiter patients (0.2 ± 0.4%), and HLA-A2-positive healthy controls (0.1 ± 0.2%). The frequency of Tg-specific T cells (3.0%) was very similar to those of TPO-specific CD8-positive T cells (2.9%). Subgroup analyses revealed a steady increase of the number of epitope-specific CD8-positive T cells from 0.6 ± 1.0% at initial diagnosis up to 9.4 ± 18.3% in patients with long-lasting disease. Analyses of the number of thyroid-infiltrating cells as well as the cytotoxic capacity revealed a similar picture for TPO- and Tg-specific T cells.
  
  
  CONCLUSIONS
  We here report for the first time that both antigens, TPO and Tg, are recognized by CD8-positive T cells and are involved in the thyroid destruction process leading to clinical disease manifestation.
authors.affiliation: Department of Endocrinology, Diabetes, and Rheumatology, University Hospital Duesseldorf, Moorenstrasse 5, D-40225 Duesseldorf, Germany.
authors.forename: Margret
authors.initials: M
authors.lastname: Ehlers
authors.forename: Annette
authors.initials: A
authors.lastname: Thiel
authors.forename: Christian
authors.initials: C
authors.lastname: Bernecker
authors.forename: Dominika
authors.initials: D
authors.lastname: Porwol
authors.forename: Claudia
authors.initials: C
authors.lastname: Papewalis
authors.forename: Holger S
authors.initials: HS
authors.lastname: Willenberg
authors.forename: Sven
authors.initials: S
authors.lastname: Schinner
authors.forename: Hubertus
authors.initials: H
authors.lastname: Hautzel
authors.forename: Werner A
authors.initials: WA
authors.lastname: Scherbaum
authors.forename: Matthias
authors.initials: M
authors.lastname: Schott
mesh_terms: D000328:Adult; D000368:Aged; D000918:Antibody Specificity; D000920:Antibody-Dependent Cell Cytotoxicity; D001323:Autoantibodies / Q000032:analysis* / Q000737:chemistry; D001324:Autoantigens / Q000737:chemistry; D044963:Biopsy, Fine-Needle; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D000939:Epitopes / Q000032:analysis / Q000737:chemistry; D005260:Female; D006042:Goiter / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015789:HLA-A2 Antigen / Q000378:metabolism; D050031:Hashimoto Disease / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007111:Immunity, Cellular; D007453:Iodide Peroxidase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D033862:Iron-Binding Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D013954:Thyroglobulin / Q000037:antagonists & inhibitors* / Q000737:chemistry; D013961:Thyroid Gland / Q000276:immunology* / Q000473:pathology; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D000939:Epitopes; D015789:HLA-A2 Antigen; D033862:Iron-Binding Proteins; C006606:anti-thyroglobulin; D013954:Thyroglobulin; C056658:TPO protein, human; D007453:Iodide Peroxidase