Fig. 1.

Trajectories for generating cells for accurate BMECs for in vitro BBB models. The relative position of cell sources is dependent on the specific observable characteristics, while the target comparison to human BMECs is specific to zonation, brain region, age, sex, ethnicity, and disease state. Cell engineering approaches can improve aspects of BBB model accuracy while also impairing other aspects. Achieving high accuracy will require further developments in cell and tissue engineering