T-cell surface glycoprotein CD3 and undisclosed tumor antigen (CD3 x TAA)

T-cell surface glycoprotein CD3 and undisclosed tumor antigen refers to a therapeutic target pair used in the development of bispecific T-cell engagers (BiTEs) or bispecific antibodies (bsAbs). The CD3 component is a multi-protein complex, specifically the epsilon subunit, which is essential for T-cell receptor signaling and T-lymphocyte activation (UniProt P07766). The undisclosed tumor antigen refers to a proprietary or unspecified surface protein on cancer cells that the therapeutic agent is designed to recognize. By binding both CD3 and the tumor antigen, these drugs create a physical bridge between cytotoxic T-cells and malignant cells, bypassing the need for MHC-restricted antigen presentation (Labrijn et al., 2019). This proximity triggers the formation of an immunological synapse, leading to T-cell degranulation and the release of perforins and granzymes that induce tumor cell apoptosis. This dual-targeting approach is a major pillar of modern oncology, used to treat various hematologic and solid malignancies (PubMed PMID: 30633432). Clinical use of these agents is often associated with systemic inflammatory responses, most notably cytokine release syndrome (CRS) and neurotoxicity (Shimabukuro-Vornhagen et al., 2018). The undisclosed status of the antigen is common in early-stage clinical pipelines where the specific molecular target is kept confidential for intellectual property reasons.

Other names

CD3 and tumor-associated antigenCD3-bispecific targetT-cell engager targetCD3 x Undisclosed antigen

Simultaneous binding to the CD3 epsilon subunit of the T-cell receptor and a tumor-associated antigen to facilitate T-cell mediated lysis of cancer cells (Labrijn et al., 2019).