The choroid plexus is located in the ventricles of the brain where cerebrospinal fluid (CSF) is produced. It participates in brain development, maturation, aging, endocrine regulation, neuroimmune interactions, and pathogenesis of certain neurodegenerative diseases. The choroid plexus consists of a network of capillaries enclosed by a single layer of epithelial cells that together form the blood-CSF barrier. Capillaries in the choroid plexus contain a single layer of endothelial cells interrupted by “pores” which exhibit a diaphragm between the lumen and the interstitial space. Studies have shown that choroid plexus endothelial cells express high levels of Glut1 glucose transporter, which supports the idea that epithelial and endothelial cells in the choroid plexus provide a metabolic work capability for maintaining ionic gradients and secretory functions across the blood-CSF barrier. HCPEC from ScienCell Research Laboratories are isolated from human brain. HCPEC are cryopreserved at passage one and delivered frozen. Each vial contains >5 x 105 cells in 1 ml volume. HCPEC are characterized by immunofluorescence with antibodies specific to VWF/Factor VIII and/or CD31 (PECAM1). HCPEC are negative for HIV-1, HBV, HCV, mycoplasma, bacteria, yeast, and fungi. HCPEC are guaranteed to further culture under the conditions provided by ScienCell Research Laboratories; however, HCPEC are not recommended for expanding or long-term cultures due to limited expansion capacity. Recommended Medium It is recommended to use Endothelial Cell Medium (ECM, Cat. #1001) for culturing HCPEC in vitro.