Figure 2.

Example of different organ-on-a-chip (OoC) design for the Blood-Brain-Barrier (BBB) and the brain: (a) a pumpless 2D microfluidic device mimicking the BBB and hosting a coculture of iBMECs and rat primary astrocytes, (b) a 3D BBB-on-a-chip, with iPSC-derived ECs and human primary astrocytes and pericytes embedded in a fibrin hydrogel in a microfluidic system, (c) a 2D microfluidic device hosting iPSC-derived dopaminergic, glutamatergic and GABAergic neurons in different chambers connected by microgrooves enabling connectivity studies, (d) NVU-on-a-chip microfluidic device with the BBB constituted by primary human BMVECs, astrocytes, and pericytes and the brain by iPSC-derived neurons and astrocytes embedded in a 3D collagen gel, and (e) a schematic example of an iPSC-derived brain organoid developed in a microfluidic device, embedded in a 3D Matrigel matrix. Created with BioRender.com.

Source: Adapted with permission from Wang et al. ¹⁰⁴ in Biotechnol. Bioeng., Lee et al. ¹⁰⁸ in Adv. Healthc. Mater., Fantuzzo et al. ¹¹⁴ in Technology, Brown et al. ¹¹⁵ in J. Neuroinflammation, Wang et al. ¹¹⁶ in Lab Chip.

iBMECs: induced brain endothelial cells; BBB: blood-brain-barrier; iPSCs: induced pluripotent stem cells; ECs: endothelial cells; GABA: gamma-Aminobutyric acid; NVU: neurovascular unit; BMVEC: brain microvasculature endothelial cells.