TEDxCaltech: Surmounting the Blood-Brain Barrier

This week we will be highlighting the student speakers who auditioned and were selected to give five-minute talks about their brain-related research at TEDxCaltech: The Brain, a special event that will take place on Friday, January 18, in Beckman Auditorium. 

In the spirit of ideas worth spreading, TED has created a program of local, self-organized events called TEDx. Speakers are asked to give the talk of their lives. Live video coverage of the TEDxCaltech experience will be available during the event at http://tedxcaltech.caltech.edu.

That fact stood out to Caltech MD/PhD candidate and TEDxCaltech speaker Devin Wiley when he was studying medicine at the Keck School of Medicine of USC. "In certain cases, one bacterium detected in the brain can be a medical emergency," he says. "So the microenvironment needs to be highly protected and regulated for the brain to function correctly."

Fortunately, a semipermeable divide, known as the blood-brain barrier, is very good at maintaining such an environment for the brain. This barricade—made up of tightly packed blood-vessel cells—is effective at precisely controlling which molecules get into and out of the brain. Because the blood-brain barrier regulates the molecular traffic into the brain, it presents a significant challenge for anyone wanting to deliver therapeutics to the brain. 

At Caltech, Wiley has been working with his advisor, Mark Davis, the Warren and Katharine Schlinger Professor of Chemical Engineering, to develop a work-around—a way to sneak therapeutics past the barrier and into the brain to potentially treat neurologic diseases such as Alzheimer's and Parkinson's. The scientists' strategy is to deliver large-molecule therapeutics (which are being developed by the Davis lab as well as other research groups) tucked inside nanoparticles that have proteins attached to their surface. These proteins will bind specifically to receptors on the blood-brain barrier, allowing the nanoparticles and their therapeutic cargo to be shuttled across the barrier and released into the brain.

"In essence, this is like a Trojan horse," Wiley explains. "You're tricking the blood-brain barrier into transporting drugs to the brain that normally wouldn't get in."

During his five-minute TEDxCaltech talk on Friday, January 18, Wiley will describe this approach and his efforts to design nanoparticles that can transport and release therapeutics into the brain.

For Wiley, the issue of delivering therapeutics to the brain is more than a fascinating research problem. His grandmother recently passed away from Alzheimer's disease, and his wife's grandmother also suffers from the neurodegenerative disorder.

"This is something that affects a lot of people," Wiley says. "Treatments for cardiovascular diseases, cancer, and infectious diseases are really improving. However, better treatments for brain diseases are not being discovered as quickly. So what are the issues? I want to tell the story of one of them."