Fig. 1

CAR structure. All different generations of CAR are composed of an extracellular antigen- binding domain (usually derived from an an antibody and engineered into an scFv), a hinge region, a transmembrane domain and various intracellular domains. First generation CARs have CD3ζ as the only signaling domain. In second generation CARs, one costimulatory domain was added, while third generation contain both CD28 and 4-1BB costimulatory signalling domains