Fig. 2.
a Pathogenic autoantibodies stimulating the orbital fibroblasts resulting in production of hyaluronan and giving rise to symptoms of thyroid eye disease. b Teprotumumab (an IGF-1R antagonist) blocks the stimulatory effects of pathogenic autoantibodies on the orbital fibroblasts TSI thyroid stimulating immunoglobulins, GD-IgG Graves’ disease immunoglobulins, TSHR thyroid stimulating hormone receptor, IGF-1R insulin-like growth factor-1 receptor