Intrathyroidal lymphocyte subsets, including unusual CD4+ CD8+ cells and CD3loTCR alpha beta lo/-CD4-CD8- cells, in autoimmune thyroid disease.
Intrathyroidal lymphocyte subsets were analysed in 13 euthyroid patients with autoimmune thyroid disease by two-colour flow cytometry and compared with subsets in peripheral blood. In both Graves' and Hashimoto's diseases, proportions of intrathyroidal CD5- B cells were higher than in peripheral blood. The numbers of such cells were correlated with serum levels of anti-thyroid microsomal antibodies. Proportions of T cells bearing alpha beta chains of T cell receptors (TCR alpha beta+ T; T alpha beta) and CD16+CD57+ natural killer (NK) cells were lower in the thyroid, but proportions of CD3hiTCR alpha beta-TCR gamma delta+ (T gamma delta) cells were not different. Proportions of CD4+Leu-8- helper T cells and CD4+CD57+ germinal centre T cells were higher and proportions of CD4+Leu-8+ suppressor-inducer T cells and CD8+CD57+ or CD8+CD11b+ suppressor T cells were lower than in the blood in both diseases. Proportions of CD5+ B cells were high in Graves' disease, and proportions of CD8+CD11b- cytotoxic T cells were high in Hashimoto's disease. Unexpectedly, CD4+CD8+ cells and CD3loTCR alpha beta lo/-CD4-CD8- cells were present in thyroid tissues of both diseases. These findings suggest that: (i) an imbalance in the numbers of regulatory T cells and of NK cells that had appeared in the thyroid resulted in the proliferation of CD5- B cells, which were related to thyroid autoantibody production; (ii) CD5+ B cells and cytotoxic T cells are important for the different pathological features in Graves' and Hashimoto's diseases, respectively; and (iii) intrathyroidal CD4+CD8+ cells and CD3loTCR alpha beta lo/-CD4-CD8- cells may be related to the pathogenesis of autoimmune thyroid disease.
Iwatani
Y
Y
Department of Laboratory Medicine, Osaka University Medical School, Japan.
Hidaka
Y
Y
Matsuzuka
F
F
Kuma
K
K
Amino
N
N
D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000032:analysis; D017252:CD3 Complex / Q000032:analysis; D015704:CD4 Antigens / Q000032:analysis*; D016827:CD8 Antigens / Q000032:analysis*; D005260:Female; D006111:Graves Disease / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013967:Thyroiditis, Autoimmune / Q000276:immunology*
D015703:Antigens, CD; D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D016693:Receptors, Antigen, T-Cell, alpha-beta