Figure 1.

Schematic of assay setup. MDCKII/MDR1 cells were cultured as a monolayer in HTS 96-well Transwell inserts. While the in vitro BBB was forming, LN-229 cells were seeded in a spheroid microplate to generate glioma spheroids, which then became the receiver microplate for the Transwell inserts. Upon addition of cytotoxic drugs to the apical chamber of the inserts, the components were incubated together temporarily to allow for drug diffusion across the BBB. Spheroids were cultured for an additional 2 days without inserts, then assayed for cell viability with CellTiter-Glo 3D.