Blood-brain Barrier (IMAGE) Harvard Medical School Caption Normal brain blood vessels completely contain a fluorescent dye (left). Vessels without the lipid transport protein Mfsd2a show a leaky blood-brain barrier. Credit Gu Lab/Harvard Medical School Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.