Blood-Brain Tumor Barrier or BBTB Model: An Adaption of the Blood-Brain Barrier or BBB Model to Evaluate Delivery of Therapeutics to the Tumor

The blood-brain barrier, or BBB, is a selective barrier of endothelial cells and brain cells such as astrocytes that regulates the transport of substances between the blood and the brain.

To develop a BBB model, invert a membrane insert onto a culture plate lid.

Seed astrocytes over the membrane. Place the culture plate over the insert and incubate.

This entraps the astrocytes between the membrane and the well surface.

Revert the plate to bring astrocytes to the bottom and add a suitable medium to the well.

To the insert, add endothelial cells expressing optimal tight junction proteins that enhance cell-to-cell contacts necessary for barrier formation.

Incubate to allow endothelial cells to adhere to the membrane.

Remove the spent medium and transfer the insert to another well-containing growth factor-free astrocyte medium.

Subsequently, add a growth factor-free endothelial cell medium to the insert and incubate.

The absence of growth factors inhibits cell division, preserving cell-to-cell contacts and stabilizing the barrier properties.

The endothelial cells and astrocytes interact to form a basement membrane with tight junctions like the BBB.

Next, seed glioma spheroids in a new culture well.

Transfer the BBB model over these spheroids and incubate to form the blood-brain tumor barrier or BBTB model.

Add target molecules to the BBTB model to assess their delivery to the tumor site.