Changes of serum TSI, TGI and peripheral blood T lymphocyte subsets in patients with graves disease before and after therapy

Thyroid stimulating immunoglobulin (TSI) and thyroid growing immunoglobulin (TGI) were measured and pan T cells (CD3), helper/inducer T cells (CD4) and suppressor/cytoxic T cells (CD8) in peripheral blood were enumerated in 37 patients with Graves disease and 32 normal individuals. The results showed that the positive rates of TSI and TGI were 83.8% and 58.3% respectively in patients with Graves disease. The TSI activity was positively correlated with the level of serum TT4 (P<0.01). TGI was correlated with the goitre size (P<0.05). The percentages of CD3+ cells and CD8+ cells were decreased (P<0.01) and the CD4+/CD8+ ratio increased (P<0.05) in 37 cases with Graves disease. At the sixth week of treatment with methimazole in eighteen cases of 37 patients with Graves disease, the levels of serum thyroid hormones were recovered. The TGI activity, the percentages of CD3+ and CD8+ cells, and the CD4+/CD8+ ratio were not changed obviously. Pathogenic roles and clinical significance of serum TSI, TGI and peripheral blood T lymphocyte subsets in Graves disease were also discussed