Neural progenitor cell differentiation. Fluorescence light micrograph of neural progenitor cells that have been grown in a medium that is selective for astrocytes for three weeks. Neural progenitor cells are able to differentiate into neurons (nerve cells) or support cells (glial cells), which include astrocytes. Astrocytes have been stained orange and neural progenitor cells green. Cell nuclei are blue. Neural progenitor cells are a potential source of cells to replace damaged or lost brain cells.