examined how these expressions changed with the culture. The co-culture of neurons (stage 3 in Figure 1I) with ECs and pericytes partially increased BBB-specific transporters and receptors. In contrast, co-culture of astrocytes (stage 5 in Figure 1I) with ECs and pericytes did not lead to an increase. Importantly, the co-culture of both neurons and astrocytes with ECs and pericytes was most efficient at inducing BBB-specific transporters and receptors (Figure S2). These results indicated that cell-cell communication between ECs and neurons and astrocytes is crucial in acquiring ciBEC properties.
