Abstract
Spontaneous development of TSH receptor (TSHR) autoantibodies that cause Graves' hyperthyroidism is limited to humans and the lack of a spontaneous animal model has seriously hampered elucidating the pathogenesis of this common autoimmune disease. Recently, a novel animal model was developed in Chiba, Japan, that clearly mimics some of the major features of Graves' hyperthyroidism. Unlike previous approaches involving immunization with soluble antigen and adjuvant (reviewed in[1]), in this model, mice are injected intraperitoneally with fibroblasts co-expressing both syngeneic MHC class II and the human TSHR.[2] After 6 injections, ∼ 80% of animals developed TSH binding inhibiting immunoglobulins (TBI) and ∼ 25% were clearly thyrotoxic with elevated thyroid hormone (T3 and T4) levels. Thyrotoxicosis is even fatal to some animals.[3]