T-cell receptor complex and tumor-associated antigen (TCR-TAA)

The T-cell receptor (TCR) complex and tumor-associated antigen (TAA) interaction represents a therapeutic target paradigm where a drug, typically a bispecific antibody, bridges a T cell and a tumor cell (Huehls et al., 2015). The TCR complex, specifically the CD3 epsilon subunit (UniProt P07766), is engaged to trigger T-cell activation, while the TAA (such as CD19, CD20, or BCMA) provides the specificity for the malignant cell (Labrijn et al., 2019). This engagement creates an artificial cytolytic synapse, allowing the T cell to release cytotoxic granules like perforin and granzymes directly onto the tumor cell, leading to its destruction (Baeuerle and Reinhardt, 2009). This mechanism is MHC-independent, meaning it can bypass tumor escape mechanisms like MHC downregulation. Drugs targeting this interaction, such as Blinatumomab and Teclistamab, have revolutionized the treatment of hematologic malignancies but are associated with significant toxicities, including cytokine release syndrome (CRS) and neurotoxicity (Shimabukuro-Vornhagen et al., 2018). The success of this approach depends on the density of the TAA on the tumor surface and the presence of functional T cells in the microenvironment.

Other names

CD3 and tumor-associated antigenT-cell redirecting targetBispecific T-cell engager targetTCR-CD3 and TAA interaction

Bispecific T-cell redirection and MHC-independent T-cell activation leading to targeted tumor cell lysis.