One of the great challenges for treating Parkinson’s diseases and other neurodegenerative disorders is getting medicine to the right place in the brain. The brain is a complex organ with many different types of cells and structures, and it is fortified with a protective barrier erected by blood vessels and glial cells -- the brain’s structural building blocks -- that effectively blocks the delivery of most drugs from the bloodstream. But now scientists have found a new way to sneak drugs past the blood-brain barrier by engineering and implanting progenitor brain cells derived from stem cells to produce and deliver a critical growth factor that has already shown clinical promise for treating Parkinson’s disease. Writing this week (Dec. 15, 2005) in the journal Gene Therapy, University of Wisconsin-Madison neuroscientist Clive Svendsen and his colleagues describe experiments that demonstrate that engineered human brain progenitor cells, transplanted into the brains of rats and monkeys, can effectively integrate into the brain and deliver medicine where it is needed.
