Figure 5

Progress towards an all-human stem cell-derived in vitro BBB model. hPSCs can be co-differentiated as a mixture of neural cells and BMECs, and the BMECs can be subcultured as a pure monolayer expressing typical endothelial and BBB markers such as PECAM-1, VE-cadherin, occludin, and claudin-5. Several options are theoretically possible for creating an all-human BBB model with these hPSC-derived BMECs. Human NPCs could potentially be used to create a BMEC/NPC co-culture model as a representative in vitro model of the developing human BBB. Alternatively, human NPCs could be pre-differentiated into mixed neuron/astrocyte cultures to model the adult BBB. Ideally, future applications will involve using hPSCs to obtain all the different cells forming the neurovascular unit. This approach could also facilitate the use of hiPSCs derived from both healthy and diseased patients to obtain a physiological or diseased model of the human BBB in vitro. Scale bar indicates 25 μm.