Figure 7.

Properties of BBB in vitro models. (a) Transwell systems utilize a porous filter insert that divides culture wells into luminal and abluminal compartments and allows for diffusion of molecules and cell migration across the filter. (b) Microfluidic devices recapitulate a more complex tissue environment in vitro by co-culturing cells in 2D and 3D matrices. Parameters including shear stress and gradient formation are tunable to establish a controlled microenvironment. Microfluidics enable integration of sensing systems and high-resolution microscopy. Multichannel designs allow samples to be screened in parallel, creating compact medium-throughput systems for simulating biological conditions and enabling drug screening. Brain EC are shown in pink on the luminal side, and brain pericytes are marked in green on the abluminal side.