Microphysiological systems (MPS) incorporate physiologically relevant microanatomy, mechanics, and cells to mimic tissue function. MPS can be used for drug screening, developmental biology, pathology, and toxicology research. Uniquely enabled by in situ formation of 3D tissue, we engineered a MPS of the BBB (MPS-BBB) without a semi-permeable membrane, therefore simplifying assembly, enabling high-resolution imaging, and promoting astrocyte-endothelial interactions. Consequently, this system better recapitulates in vivo cellular pathways and functions. Characterization beyond post facto techniques is enabled through impedance monitoring of barrier fidelity with an in-line electrode array. In-line monitoring provides for real-time analyses to infer barrier development, dysfunction, and repair.
