The blood brain barrier (BBB) is a specialized capillary bed that separates the brain from the circulatory system and protects the brain from most pathogens [1]. Endothelial tight junctions supported by pericytes and astrocytes are primarily responsible for the highly selective nature of the BBB, restricting the passage of numerous solutes, most antibodies, and some antibiotics [2]. As such, efforts to understand the mechanisms underlying BBB integrity have been critical to developing techniques that are able to penetrate the BBB to deliver therapeutic or diagnostic molecules to the brain. Due to the complexities of the BBB, it is difficult to study in a 2-dimensional in vitro system, which inherently lacks multiple aspects of the physiological microenvironment. ScienCell™’s 3-dimensional blood brain barrier modeling kit (3D-BBB) co-cultures endothelial cells, pericytes, and astrocytes in collagen I matrix with a defined serum-free medium to replicate intercellular interactions at the BBB.