How Parkinson's Disease Protein Spreads (IMAGE) University of Pennsylvania School of Medicine Caption These images show the brainstem from a control animal (top) and an animal injected with pathologic alpha-synuclein. Brown spots are immunostaining using an antibody specifically recognizing an abnormal form of alpha-synuclein. Credit Kelvin C. Luk, Ph.D., Perelman School of Medicine, University of Pennsylvania Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.