The choroid plexus is located in the ventricles of the brain where cerebrospinal fluid (CSF) is constantly produced. It consists of a network of capillaries enclosed by a single layer of epithelial cells that together form the blood-CSF barrier. Choroid plexus epithelial cells (CPEpiC) play a central role in restricting the passage of molecules and ions between the brain and CSF by the junctional complexes between neighboring cells. They also have a special cellular structure, and channel and transporter protein expression well-adapted for CSF secretion. A previous study further demonstrated that CPEpiC respond to ischemic and traumatic insults in the central nervous system by synthesizing and secreting various growth factors and peptides with trophic benefits that work through autocrine and paracrine mechanisms to facilitate recovery. CPEpiC cultures serve as an excellent model to study the exchange processes across blood-CSF barrier, CSF homeostasis, and more.