BBB

Once developed, this assay can be used by any lab to understand the results of their experimentation. The design for the assay also uses the Tet-On system. Doxycycline is a drug which cannot normally penetrate the BBB. This means that under normal circumstances, the Tet gene will not activate. Adding a drug which breaks down the BBB allows doxycycline to penetrate, and gene transcription to occur. Using a fluorescent protein as the Tet product, a baseline level of fluorescence when only doxycycline is added could be determined. Using that level as a control, the effectiveness of a drug could be determined. If the drug breaks down the BBB, doxycycline will more readily enter the brain, and more fluorescent product would be produced.