Astrocytes and Reduced Myelin (IMAGE) City of Hope Caption An Alexander disease patient's stem cell-derived astrocytes (green) inhibits the growth of precursor cells that become myelin and speed up the brain's communication network. Credit Yanhong Shi/City of Hope Usage Restrictions Please use the credit as is. 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.