A representation of the CAR-T therapy process is shown. Cells are harvested from patients by apheresis. T cells are activated and genetically modified with a CAR gene that will lead to expression of a CAR protein on the T cells. Genetic modification is carried out with a gene-therapy vector such as a γ-retrovirus or a lentivirus. CAR-expressing T cells proliferate ex vivo. Patients often receive a chemotherapy conditioning regimen to deplete endogenous leukocytes with a goal of enhancing CAR-T activity. After completion of the conditioning chemotherapy regimen, CAR-Ts are infused. Professional illustration by Patrick Lane, ScEYEnce Studios.