Figure 6.

On-switch CAR and iCAR. (A) The on-switch CAR-T cells are initially turned off, activated only with specially designed drugs, then recognize, bind to, and kill the targeted tumor cells. When the drugs are not present, the CAR-T cells return to their off state; (B) When iCAR-T cells bind to the corresponding tumor cells, iCAR-T cells are activated and kill the tumor cells. Nonetheless, when iCAR-T cells combine with normal cells, the iCARs produce inhibitory signals which prevent traditional CARs or TCRs from functioning, thus the normal cells remain undamaged.