Tumor cell ligands for γδ T cell receptors

Tumor cell ligands for γδ T cell receptors (TCRs) are a diverse group of cell surface molecules that enable γδ T cells to recognize and eliminate malignant cells in an MHC-independent manner. These ligands, which include the Butyrophilin family (specifically BTN3A1 and BTN2A1), MHC class I-related molecules (MICA and MICB), and UL16-binding proteins (ULBPs), serve as "stress signals" that are upregulated in response to metabolic dysregulation or genomic instability. The Butyrophilin complex is essential for the activation of Vγ9Vδ2 T cells, the major γδ subset in human blood, by sensing intracellular phosphoantigens that accumulate in tumor cells. In contrast, MICA and MICB are primarily recognized by the Vδ1 T cell subset, which is often found infiltrating solid tumors. Therapeutic strategies targeting these ligands include agonistic monoclonal antibodies, such as ICT01 which targets BTN3A to trigger γδ T cell-mediated cytotoxicity, and agents that prevent the shedding of MICA/B from the tumor surface. Additionally, certain small molecules like aminobisphosphonates indirectly modulate these ligands by inducing the accumulation of phosphoantigens that stabilize the BTN3A1/BTN2A1 complex for TCR recognition.

Other names

γδ T-cell receptor ligandsγδ TCR ligandsTumor-associated γδ T-cell ligandsButyrophilins and MHC class I-related molecules

Agonism of butyrophilin proteins (specifically BTN3A) to activate Vγ9Vδ2 T cells; Indirect activation via phosphoantigen accumulation; Prevention of ligand shedding from tumor cells to maintain immune visibility.