Behaviour of thyroid tissue from patients with Graves' disease in nude mice

Thyroid tissue from five patients with hyperthyroidism due to Graves' disease was transplanted into nu/nu mice (2 to 4 mice per thyroid) in order to assess whether the tissues would remain hyperfunctional. Before surgery, the patients received only propranolol and iodine for ten days. Transplants were removed from the mice after 10, 20, 30 or 57 days, and compared to the initial tissue, as well as toxic nodules from two patients and thyroid tissue from two normal subjects grafted similarly. All transplants survived, as proven by histology and autohistoradiography with 131I uptake, while all signs of hyperfunction and dysimmunity disappeared. Conversely, both transplanted toxic nodules remained hyperfunctional. These results indicate that, in spite of the in situ presence of most factors of auto-immune reactions, thyroid tissue from patients with Graves' disease is not autonomous and depends on the extra-thyroid environment.