Contribution of a Snake Venom Toxin to Myasthenia Gravis: The Discovery of α-bungarotoxin in Taiwan

Abstract

Myasthenia gravis (MG) is now recognized as an autoimmune disorder in which antibodies to acetylcholine (ACh) receptor lead to impairment of neuromuscular transmission. The discovery of α-bungarotoxin by Chang and Lee in 1963 has played a crucial role in establishing the new concept of MG. However, isolation of bungarotoxins from the venom of Taiwan banded krait, Bungarus multicinctus, was accomplished in the poorly funded and under equipped laboratory of the Department of Pharmacology, National Taiwan University, during the post-WWII period of economic depression and research isolation. Because α-bungarotoxin binds specifically and irreversibly with the muscle type nicotinic ACh receptor, it was used to localize ACh receptor and to isolate the ACh receptor protein, opening up a new era of receptor studies. It was also used to produce an antibody to ACh receptor and eventually an experimental autoimmune model of MG and clinical confirmation. The discovery of α-bungarotoxin has been considered the most important contribution to neurosciences from Taiwan.