Chimeric antigen receptor signaling domain (tumor antigen-specific) (CAR signaling domain)

The tumor antigen-specific chimeric antigen receptor (CAR) signaling domain is the engineered portion of a synthetic CAR protein expressed in cell therapies (CAR-T cells). Located intracellularly, this domain typically includes portions from native immune signaling molecules (such as CD3ζ, CD28, or 4-1BB), and is responsible for transmitting activation signals when the extracellular CAR region binds its target antigen. The combination of different signaling modules determines the functional profile and efficacy of the CAR-T cell product[1][2][3][4][5][6]. The “signaling domain” is not a native human molecule, is not a direct drug target, and its entry as a target name is ambiguous and non-standard.

Other names

CAR intracellular domainCAR endodomainChimeric antigen receptor (CAR) signaling regionCAR-T cell signaling module

In engineered CAR-T cells, the “signaling domain” transduces activation signals (often via CD3ζ and costimulatory motifs such as CD28 or 4-1BB) to drive T cell responses upon antigen encounter; but the domain itself is not acted on by drugs[1][2][3][4][6]. For CAR-T drugs: - *Cellular cytotoxicity* - *Cytokine secretion* - *T cell proliferation*