Fig. 4

Establishment of blood–brain-tumor-barrier (BBTB) chip. A Schematic illustrating set up of BBB-on-CHIP systems to establish the blood–brain-tumor barrier (BBTB) model using the SynBB parallel three channel (200:500:200 µm) configuration separated by 3 µm microfabricated pores. B Immunofluorescence image of the BBTB model setup in the SynBBB CHIPs with iBECs seeded in the middle (endothelial) channel and U87vIII-mKate2 cells (red) seeded in the two outer channels. CAR-F263 (green) perfusion can be seen within the iBEC channel; arrow indicating flow direction (see also Additional file 3: Movie S2). Scale bar = 100 µm. C Phase contrast image of iBECs seeded in the centre channel and fluorescence staining for tight junction proteins OCCLUDIN, CLAUDIN 5, ZO-1 s and GLUT1 (all green) showing continuous membrane expression, cobblestone morphology and 3D lumen formation. Hoechst counterstain (blue). Scale bar = 100 µm