CD19-specific chimeric antigen receptor (CD19-CAR) (CD19-CAR)

The CD19-specific chimeric antigen receptor (CAR) is a synthetic, engineered receptor expressed on the surface of T cells to redirect their cytotoxic activity toward CD19-positive B cells. It typically consists of an extracellular single-chain variable fragment (scFv), most commonly derived from the FMC63 monoclonal antibody, linked via a hinge and transmembrane domain to intracellular signaling components such as the CD3-zeta chain and costimulatory domains like 4-1BB or CD28. While primarily utilized as a therapeutic agent for treating relapsed or refractory B-cell malignancies, the CAR itself can serve as a target for anti-idiotype antibodies and specialized safety-switch therapies designed to monitor or modulate CAR-T cell activity in vivo. In clinical practice, the interaction between the CAR and its target antigen drives potent anti-tumor responses but can also lead to significant toxicities, including cytokine release syndrome and neurotoxicity. Monitoring the persistence and function of the CD19-specific CAR on infused cells is essential for evaluating treatment efficacy and managing long-term side effects such as B-cell aplasia.

Other names

Anti-CD19 CARCD19-CARFMC63-based CARCART19 receptorCD19-specific CAR on co-infused CAR T cells

The CD19-specific CAR binds to the CD19 antigen on the surface of B cells, triggering an intracellular signaling cascade through CD3-zeta and costimulatory domains (e.g., 4-1BB or CD28), which leads to T-cell activation, proliferation, and the release of cytotoxic granules (perforin and granzymes) to lyse the target cell.