Figure 3. Transwell and dynamic in vitro blood-brain barrier (DIV-BBB) systems have been used to model blood-brain barrier development, permeability, and transport.

A. Transwell systems utilize tissue culture plate inserts containing permeable membranes that can be functionalized with proteins or peptides to permit cell attachment. The transwell inserts can be positioned within tissue culture plates for the culture of up to three cell types on separate surfaces. B. The DIV-BBB is composed of a permeable capillary tube on which cells are grown within and around. This culture setup creates a three-dimensional culture system in which multiple cell types can be cultured, and also allows endothelial cells to grow in tube-like formation. The DIV-BBB permits both the flow of medium and sampling from the cultures through ports. In the diagrams on the left, red represents luminal space and blue represents tissue space. In the diagrams on the right, purple corresponds to endothelial cells, yellow to astrocyte and red to neurons.