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The source of this article is Forbes: http://tinyurl.com/95sxq Parkinson's Disease Vaccine Shows Promise By Kathleen Doheny HealthDay Reporter WEDNESDAY, June 15 (HealthDay News) -- A vaccine to treat Parkinson's disease looks promising in a preliminary animal study, researchers report in the June issue of Neuron. "What we found is overall there was a significant decrease in disease-related changes in the mice treated with the vaccine," said study co-author Leslie Crews, a research associate at the University of California, San Diego department of neurosciences. Parkinson's disease affects about 1.5 million Americans, according to the National Parkinson's Foundation. The degenerative illness gradually triggers the death of nerve cells, or neurons, in the brain that produce the chemical dopamine, a neurochemical involved in muscle movement and function. Advancing illness is characterized by loss of balance, tremor, rigidity and other disabling symptoms. A drug called levodopa can help slow disease progression, but its effect diminishes over time. The UCSD team, led by Dr. Eliezer Masliah, a professor of neurosciences and pathology, also included researchers from Elan Pharmaceuticals, in San Francisco, which is developing the vaccine and helped fund the study. The researchers focused on two groups of mice with a simulated form of Parkinson's disease and compared their outcomes to a group of healthy, control mice. A protein called alpha-synuclein, involved in neuron-to-neuron communication, is crucial to healthy brain function. But in Parkinson's, the protein's structure changes and becomes abnormal. When too much of this abnormal protein accumulates, disease-linked brain changes begin. The new vaccine was made with the human form of alpha-synuclein and an adjuvant compound that allows it to be carried to the brain. The team vaccinated one group bred to have Parkinson's, using the vaccine and an adjuvant. They vaccinated the second group with Parkinson's with just the adjuvant. By vaccinating with the protein, the researchers hoped to spur the production of immune antibodies, which would then enter the brain and help rid it of abnormal protein accumulation. That process seems to have worked -- at least in mice, the researchers report. "All the mice treated [with the vaccine] had decreases in the level of abnormal alpha-synuclein and increases in markers that showed their brains were functioning better," said Crews. "About 50 percent of the treated mice had 'high affinity' antibodies," she said, meaning their immune response was specific to the protein injected. "In that group, the level of neural integrity brain cell function was equal to what the normal controls looked like," Crews said. "That means that basically all of the neuronal connections and cellular communication were functioning." On the other hand, "in the group treated with just the adjuvant, the markers of neuron integrity decreased by about 20 percent at about six months," she said. The research team emphasized that this form of "active immunization" may not prove useful in humans. As experiments with similar vaccines for Alzheimer's disease have shown, active immunization can result in harmful inflammation. Eventually, it might be possible to inject the antibodies themselves directly, as if the Parkinson's patient were creating his or her own supply, Masliah said in a prepared statement. While most people think of a vaccine as a way to prevent disease, in this case, Crews said, the vaccine is being studied as a treatment. "But we are currently investigating whether it would be useful as a preventive measure as well," she said. Another expert, Michael Jakowec, an assistant professor of neurology at the George and MaryLou Boone Parkinson's Disease and Movement Disorders Research Center at the University of Southern California Keck School of Medicine, Los Angeles, said the study results are "very interesting." But he added the caveat that the work is preliminary and confined to animals. "It's promising, and I think it's an approach worthy of pursuit. It comes from a strong group of well-respected scientists," he said. "At least it will underscore the importance of understanding pathology, the role of pathology in neurodegenerative disease," he said. "We [in the field] are beginning to debate, "is there a link between pathology and clinical symptoms?" ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn