Syngeneic sensitization of mouse lymphocytes on monolayers of thyroid epithelial cells. III. Induction of thyroiditis by thyroid-sensitized T lymphoblasts.

During in vitro sensitization of CBA spleen lymphocytes on syngeneic monolayers of either thyroid epithelial cells (TEC) or fibroblasts, stimulation occurs, as assessed by thymidine incorporation and lymphoblast generation. When lymphoblasts generated on syngeneic TEC are injected either into thyroid lobes of intact CBA recipients or i.v., thyroiditis appears at least 21 days after injection. Thyroiditis is assessed by both optical and electron microscopic blind studies and by the presence of antibodies in the sera directed against mouse thyroglobulin. In contrast, control animals which received identical numbers of lymphoblasts generated on syngeneic fibroblasts behaved as normal. Thyroiditis was also induced using pure thyroid-sensitized T lymphoblasts. This is the first report showing the role of T lymphocytes in the induction of experimental autoimmune thyroiditis.