What’s the News: A modified antibody can make its way into the brain and target the development of Alzheimer’s-inducing plaques, researchers reported today in two animal studies in Science Translational Medicine. The blood-brain barrier usually keeps drugs and other compounds from entering the brain in large enough quantities to be effective, but these studies show a way to trick the body’s own defenses into letting the drug in, demonstrating that this obstacle to treating Alzheimer’s could potentially be overcome.

How the Heck:

Antibodies—immune proteins that attack disease-causers like viruses and bacteria—are far too big to fit through the blood-brain barrier under normal circumstances. But because of the brain’s need for iron, one protein is routinely ferried across the barrier: transferrin, which binds to iron in the blood.
So, the researchers added a molecular structure to the antibody that essentially fooled receptors in the blood-brain barrier into treating the antibody as though it were transferrin, picking it up from the bloodstream and releasing it on the other side, into the brain. Ten times as much of the modified antibody made it past the barrier, compared to a version of ...