Disease-associated antigen recognized by the expressed CAR

The term "Disease-associated antigen recognized by the expressed CAR" refers to the specific molecular entity, typically a cell-surface protein, that a Chimeric Antigen Receptor (CAR) is engineered to detect and bind (National Cancer Institute, 2022). This antigen serves as the primary target for CAR-modified immune cells, most commonly T-cells, allowing them to identify and eliminate cells associated with a specific pathology, such as malignancy or infection (June & Sadelain, 2018). The interaction between the CAR's extracellular binding domain and the target antigen is the fundamental step in CAR-T cell activation, initiating a cascade that results in the destruction of the target cell. While CD19 is the most well-known example in B-cell malignancies, other antigens like BCMA and CD22 are also targeted by FDA-approved therapies (FDA, 2023). The selection of an appropriate disease-associated antigen is critical for therapeutic efficacy and minimizing "on-target, off-tumor" toxicity, where the CAR-T cells attack healthy tissues expressing the same antigen. This phrase is often used as a generic placeholder in clinical trial descriptions or patent filings to describe the functional target of a CAR-based therapeutic (PubMed, 2024).

Other names

Tumor-associated antigen (TAA)CAR target antigenSurface antigenTarget molecule recognized by CAR

The chimeric antigen receptor (CAR) expressed on the effector cell (typically a T-cell) binds specifically to the disease-associated antigen on the surface of the target cell. This binding event triggers intracellular signaling through the CAR's CD3-zeta and co-stimulatory domains (e.g., 4-1BB or CD28), leading to T-cell activation, proliferation, cytokine release, and direct lysis of the antigen-expressing target cell (June & Sadelain, 2018).