The blood-barrier consists of a layer of cells that line the inner surface of the capillaries that regulate the passage of nutrients and waste in and out of the central nervous system. While this barrier protects the brain from infections and toxins, it also prevents any drug molecules from entering the brain. Neurobiologist Ryan Watts and his colleagues at the biotechnology company Genentech in South San Francisco have developed a way of delivering medicines to the brain by bypassing the blood-brain barrier. They created a two-sided antibody and used the protein transferrin – which carries iron to the brain – as its vehicle. The antibody attaches one of its ends to transferrin and reaches inside the brain. The other end of the antibody then targets an enzyme called β-secretase 1 (BACE1), which produces amyloid-β, associated with Alzheimer's disease. The antibody binds itself with BACE1 tightly and prevents it from producing amyloid-β. While the antibody has been a success in monkeys, the team is looking for ways to test it in humans.
Read more in Nature.