Lewy bodies are unusual deposits or clumps of the brain protein alpha-synuclein, along with other proteins, which are seen upon microscopic examination of the brain. Many brain cells of people with Parkinsons disease contain Lewy bodies. Researchers do not yet know why Lewy bodies form or what role they play in the development of Parkinsons disease. The clumps may prevent the cell from functioning normally, or they may actually be helpful, perhaps by keeping harmful proteins locked up so that the cells can function. 
What is (are) Parkinsons Disease ?