Definition

A humanized bispecific gamma delta T-cell engager (TCE) antibody directed against both CD1d and Vdelta2, with potential immunostimulating and antineoplastic activities. Upon administration, anti-CD1d gamma delta T-cell-engaging bispecific antibody LAVA-051 binds to both CD1d-expressing tumor cells and Vgamma9Vdelta2 T cells. This activates and redirects the Vgamma9Vdelta2 T cells to CD1d-expressing tumor cells, and the Vgamma9Vdelta2 T cells secrete interferon-gamma (IFN-g) and exert direct killing of tumor cells. The Vgamma9Vdelta2 T cells also activate the immune system to exert a cytotoxic T-lymphocyte (CTL) response against tumor cells. In addition, this activates invariant natural killer T cells (iNKTs). The iNKTs secrete large amounts of various cytokines, which may activate the immune system against tumor cells. Additionally, iNKTs directly target and lyse tumor cells. CD1d, an antigen-presenting glycoprotein, plays an important role in the presentation of glycolipid antigens to iNKTs; it is also expressed by various hematologic malignancies.