Decreases in αβ T cell receptor negative T cells and CD8 cells, and an increase in CD4+CD8+ cells in active Hashimoto's disease and subacute thyroiditis

SUMMARY We examined peripheral lymphocyte subsets in patients with autoimmune thyroid disease, or subacute thyroiditis, in the active stage when possible. During destructive thyrotoxicosis arising from aggravation of Hashimoto's thyroiditis, both the numbers and proportions of αβ T cell receptor (TCR) negative T (WT31− CD3+) cells and CD8 (CD4− CD8+) cells decreased and those of CD4+ CD8+ cells increased slightly, resulting in proportional increases in CD4 (CD4+ CD8−) cells. non-T, non-B (CD5− CD19−) cells, and the CD4/CD8 cell ratio. Changes were similar in active subacute thyroiditis. During stimulative thyrotoxicosis in active Graves' disease, the numbers of such T lymphocyte subsets were not changed, but only the number of CD5+ B (CD5+CD19+) cells increased markedly, resulting in proportional decreases in total T (CD3+) cells, αβ+ TCR T (WT31+ CD3+) cells, CD8 cells, and non-T, non-B cells. A serial study of some of the patients showed opposite changes in αβ TCR− T cells, the CD4/CD8 cell ratio, and CD5+ B cells between the active stages of Graves' and Hashimoto's diseases. αβ TCR− T cells were mostly γδ TCR+ T (IIF2+ CD3+) cells in these patients. These data suggest that αβ TCR T (γδTCR+ T), CD8, and CD4+ CD8+ cells are important in thyroid destruction in Hashimoto's disease and subacute thyroiditis, and that CD5+ B cells arc important in thyroid stimulation in Graves' disease.