Definition

A bifunctional antibody fusion protein composed of an agonist antibody targeting the variable (V) beta 6 (Vb6) and beta 10 (Vb10) regions of the T cell receptor (TCR) and fused to the cytokine interleukin-2 (IL-2), with potential immunostimulating and antineoplastic activities. Upon administration, anti-TCR Vb6/Vb10/IL-2 antibody fusion protein STAR0602 selectively targets and binds to the Vb6 and Vb10 regions of the TCR expressed on a subset of alpha/beta T cells, thereby activating and expanding these alpha/beta T-cells. This promotes T-cell-mediated immune responses against tumor cells. IL-2 targets and binds to the IL-2 receptor IL2R and activates IL-2/IL-2R-mediated signaling, which further activates cytotoxic T-lymphocytes (CTLs) and natural killer (NK) cells, and induces expression of certain cytotoxic cytokines, such as interferon-gamma (IFNg) and transforming growth factor-beta (TGFb). This further enhances T-cell-mediated cytotoxic immune responses against tumor cells. Alpha/beta T cells play an important role in the adaptive immune response.