Figure 5.

Vascularized tumor spheroid model can be used to study CAR-T cell transport. a) Experimental procedure for continuous flow of T cells in vascularized tumor spheroid models. Control T cells or CAR-T cells are perfused on day 7 and recirculated for 4 days. Half-volume of conditioned media in the devices is collected every 24 h and replenished. On day 11, devices are stained with Nuclear Blue DCS1 to indicate dead cells. b,c) Sketch of continuously flow T cells in the vascularized tumor spheroid model. One reservoir of each media channel is connected to the microheart pump by tubing, while the two other reservoirs are blocked to create a closed loop and continuous flow. d) Time lapse images of CAR-T cells flowing into the MVNs. A majority of the CAR-T cells travel through the MVNs quickly with some of the cells adhering to the apical surface of the vessels close to the tumor region. White arrows point to freshly adhered T cells during the time of imaging. e) Time lapse images of CAR-T cells migration and extravasation. Yellow arrows identify a T cell patrolling in the vessels. Single slice images highlight T cells undergoing extravasation. White arrows identify the portions of the cell that have extravasated. Zoomed-in images of these two T cells are provided. f) Representative images of CAR-T cell responses in the vascularized sequential tumor spheroid group at 24, 48, and 72 h time points.