Treating muscle-specific kinase myasthenia gravis from the inside out

Myasthenia gravis (MG) with antibodies to muscle-specific kinase (MuSK) is an autoimmune disease of the neuromuscular junction with some remarkable characteristics. Although MuSK is expressed in all skeletal muscles, patients with this disease present with particularly cranial, bulbar, and respiratory muscle weakness, leading to a relatively high frequency of respiratory crises.(1) Despite several available immunosuppressive or immunomodulatory treatments, patients with MuSK MG often retain residual muscle weakness and experience more often severe muscle atrophy than patients with the more frequent MG with acetylcholine receptor (AChR) antibodies.(2) Symptomatic treatment with acetylcholinesterase inhibitors is usually ineffective or even detrimental in MuSK MG,(1) although 3,4-diaminopyridine might be effective in some patients.(3) Therefore, treatment of MuSK MG today still mostly relies on immunosuppressive treatment.(1Functional Genomics of Muscle, Nerve and Brain Disorder