T-cell receptor beta variable 6 (TRBV6) (TRBV6)

T-cell receptor beta variable 6 (TRBV6) is a specific variable segment of the T-cell receptor (TCR) beta chain, encoded by a family of genes (TRBV6-1 to TRBV6-9) [8, 10]. As a component of the αβ TCR complex, it plays a fundamental role in antigen recognition and the initiation of the adaptive immune response [8, 14]. TRBV6 is expressed on a substantial subset of the T-cell repertoire, typically accounting for 6-28% of tumor-infiltrating lymphocytes across various malignancies [3, 5]. In recent years, TRBV6 has emerged as a novel therapeutic target in oncology, particularly for 'non-clonal' T-cell activation [1, 7]. Unlike CAR-T or TCR-T therapies that target specific antigens, TRBV6-targeted agents like invikafusp alfa (STAR0602) act as T-cell agonists by binding to the germline-encoded Vβ6 region [4, 6]. These bifunctional molecules often incorporate costimulatory signals, such as IL-2 or IL-15, to selectively expand Vβ6-positive T cells and enhance their anti-tumor activity [2, 4]. This mechanism is intended to overcome the limitations of broad T-cell activators and provide a potent immune response in tumors that are resistant to conventional checkpoint inhibitors [1, 5].

Other names

TCR Vβ6TCR Vbeta6T-cell receptor beta variable 6 familyTRBV6 familyTCRBV6S1TCRBV13S3

Selective T-cell activation and expansion via non-clonal TCR binding and costimulatory signaling