Evaluation of bEnd5 cell line as an in vitro model for the blood-brain barrier under normal and hypoxic/aglycemic conditions

The purpose of the study was to assess the suitability of the mouse endothelial cell line bEnd5 as a blood-brain barrier (BBB) model under normal or pathologic (stroke) conditions. In comparison to the well‐established bovine brain endothelial cell (BBMEC) model, cultured bEnd5 monolayers reached a maximal transendothelial electrical resistance (TEER) of 121 Ω cm2 on day 7, and possessed oval and spindle shape morphology. Structurally, confluent monolayers of bEnd5 cells and BBMECs exhibit peripheral band staining of the tight junction protein ZO‐1 and occludin. Both bEnd5 and BBMECs express important tight junctional proteins, ZO‐1, occludin and claudin‐1, as well as the transporters P‐glycoprotein (P‐gp), NKCC, GLUT1, and most PKC isoforms. Marker permeability experiments suggest that bEnd5 cells form a tight barrier that compares to well‐established in vitro BBB models, such as the BBMEC. After short durations of hypoxia/aglycemia (H/A), hyperpermeability was seen in the bEnd5 endothelial monolayer compared to later time periods for BBMECs, suggesting that bEnd5 cells are more sensitive to hypoxia/algycemia treatment than BBMECs. Taken together, bEnd5 cell culture model may provide a useful in vitro model of the BBB for drug delivery studies and modeling pathological states such as oxygen glucose deprivation associated with stroke. © 2007 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 96: 3196-3213, 2007