CAR is a hybrid receptor composed of three structural domains: an ectodomain containing a tumor antigen recognition domain known as scFv; a hinge region (or spacer), a hydrophobic transmembrane domain spanning the cell membrane that typically originates from CD8α or CD28; and an endodomain, also known as an intracellular signalling domain or cytoplasmic tail (Figure 5A). The gene discussed is CD8A; the disease is neoplasm.