Macrophage-lymphocyte interaction in Graves' disease and Hashimoto's thyroiditis

The formation of macrophage-lymphocyte rosettes was studied in lymphocyte cultures from patients with Graves' disease; Hashimoto's thyroiditis, other thyroid diseases and control subjects; the cultures were incubated with normal human thyroid and other non-specific antigens. At the end of incubation, the cell pellets were smeared on slides, stained with Wright's stain and the number of rosettes determined under the microscope. The membrane immunofluorescence technique was employed to identify whether the surrounding lymphocytes were T- or B-lymphocytes. In Graves' disease and Hashimoto's thyroiditis, the mean percentages of rosette formation with crude thyroid antigen were 0.98 +/- 0.22% (mean +/- SEM), and 1.15 +/- 0.25%, respectively. These values were significantly higher than those of control lymphocytes (0.03 +/- 0.02%). Lymphocytes from other thyroid diseases also gave higher values than controls. Kidney antigen, used as a control antigen, gave negative results in Graves' disease and other thyroid diseases, but in Hashimoto's thyroiditis, the mean percentage was of borderline significance. In the direct immunofluorescent staining study using fluorescein-conjugated goat anti-human Ig determinants, including the Fab fraction of anti-human IgG, it appeared that both B- and T-lymphocytes were involved in the rosettes, although B-lymphocytes were more numerous. These results indicate that in patients with Graves' disease and Hashimoto's thyroiditis, a probable immune reaction with thyroid antigen can be demonstrated by macrophage-lymphocyte rosette formation.