The thymus and myasthenia gravis.

Self acetylcholine receptor (AchR) is targeted by a wayward immune response in myasthenia gravis (MG). The current understanding of the pathogenesis of the AChR-directed immune response is reviewed. Furthermore, the thymus is suspected of initiating and perpetuating the disease process in the majority of patients; its role as a central and peripheral lymphoid organ in MG is discussed. MG seems to result from a failure of (1) establishing tolerance to the AChR and (2) regulating the immune response.