Real-time acquisition of transendothelial electrical resistance in an all-human, , 3-dimensional, blood-brain barrier model exemplifies tight-junction integrity.

The blood-brain barrier (BBB) consists of endothelial cells, astrocytes, and pericytes embedded in basal lamina (BL). Most models use nonhuman, monolayer cultures for therapeutic-delivery studies, relying on transendothelial electrical resistance (TEER) measurements without other tight-junction (TJ) formation parameters. We aimed to develop reliable, reproducible, 3-dimensional (3D) models incorporating relevant human, cell types and BL proteins.