Figure 1

Structure of an antibody-based CAR. The T-cell receptor/CD3 complex (TCR) is comprised of six proteins: α, β, γ, δ, ɛ and ζ. The structure of the αβ receptor chains is analogous to the Fab portion of an antibody with variable (V) and constant (C) domains. γ, δ and ɛ also have Ig-like extracellular domains. Boxes in the cytoplasmic domains represent signaling motifs in all chains except α and β. Antibody V regions are engineered to create an sFv and then linked to the signaling portion of ζ, in this IgTCR CAR representation, via an intervening spacer derived from the hinge portion of CD8α.