Biomedical Beat Blog – National Institute of General Medical Sciences

A network of capillaries supplies brain cells with nutrients. Tight seals in their walls keep blood toxins—and many beneficial drugs—out of the brain. Credit: Dan Ferber, PLOS Biol 2007 Jun; (5)6:E169. CC by 2.5

The blood-brain barrier—the ultra-tight seal in the walls of the brain’s capillaries—is an important part of the body’s defense system. It keeps invaders and other toxins from entering the human brain by screening out dangerous molecules. But the intricate workings of this extremely effective barrier also make it challenging to design therapeutics that would help us. And as it turns out, getting a drug across the blood-brain barrier is only half the battle. Once it’s across, the drug needs to effectively target the right cells in the brain tissue. With this in mind, it’s no surprise that challenges this complex are solved through collaboration among scientists from several different specialties.

Elizabeth Nance, an assistant professor of chemical engineering at the University of Washington in Seattle and a recent recipient of the Presidential Early Career Award for Scientists and Engineers (PECASE), focuses her research on understanding the barriers in the brain and other cell- and tissue-based barriers in the body to see how nanoparticles interact with them. Her lab uses nanoparticles to package therapies that will treat newborn brain injury, which can occur when the brain loses oxygen and blood flow, often during or immediately prior to delivery. This damage can lead to cerebral palsy, developmental delays, or sometimes death. Early interventions for newborn brain injury can be valuable, but they need to target specific, injured cells without harming healthy ones.