CD30 expression and interleukin-4 and interferon-gamma production of intrathyroidal lymphocytes in Graves' disease

We reported that serum levels of interleukin-5 (IL-5) and soluble CD30, mai nly secreted from T helper 2 (Th2) cells, were increased in Graves' disease . To clarify the immune balance of Th1/Th2 within the Graves' thyroid gland , we have compared the expression of CD30, a preferential marker for T cell s producing type 2 cytokines, and the production of interferon-gamma (IFN-g amma) and IL-4 between intrathyroidal lymphocytes (ITL) and peripheral bloo d lymphocytes (PBL). In PBL, none of these parameters were different betwee n patients and normal subjects. The proportion of CD30(+) cells in ITL was markedly higher (5.1% +/- 2.8%, P < 0.0001) than that in patients' PBL (0.4 % +/- 0.3%). Likewise, both the proportions of IFN-gamma(+) (14.8% +/- 5.5% ) and IL-4(+) cells (2.4% +/- 0.5%) in ITL were higher than those in PBL (9 .6% +/- 2.5%; p < 0.01, 1.5% +/- 0.4%; p < 0.0001, respectively). The propo rtion of type 0 (both IFN-gamma and IL-4 positive, 1.0% +/- 0.4% p < 0.001) , type 1 (IFN-gamma positive, 14.0% +/- 5.6%, p < 0.01) or type 2 cells (IL -4 positive, 1.4% +/- 0.5%, P < 0.05) in Ln was significantly higher as com pared with those in PBL (0.4% +/- 0.1%, 9.0% +/- 2.4%, 1.1% +/- 0.3%, respe ctively). The ratios of ITL/PBL in CD30+ (23.3 +/- 30.6) and type 0 cells ( 2.5 +/- 1.2) were higher than the ratios in other subsets. The proportion o f CD30+ cells correlated with the proportion of type 0 cells (r = 0.686, p < 0.01), but not with type 1 or type 2 cells. These findings suggest that t here is no obvious deviation of Th2/Th1 profile in the Graves' thyroid glan d, although intrathyroidal CD30(+) T cells and Th0 cells may play some role in the development of autoimmune abnormalities in Graves' disease.