CD96

CD96 (TACTILE, T-cell activation increased late expression) is an immunoglobulin superfamily receptor that emerged as an inhibitory checkpoint controlling NK-cell function. CD96 is a type I transmembrane glycoprotein with three extracellular Ig-like domains expressed on T cells (transiently on activated CD8+ T cells) and constitutively on NK cells and NKT cells. Its principal ligand is CD155 (PVR/necl-5), shared competitively with the activating receptor DNAM-1 (CD226) and the inhibitory receptor TIGIT; a second ligand is CD111 (nectin-1). Through its ITIM-like cytoplasmic motif, CD96 attenuates NK-cell and CD8+ T-cell cytotoxicity and interferon-γ production, restricting immunopathology during viral infection, while the DNAM-1-CD96-TIGIT balance dictates NK-cell education. CD96 blockade in preclinical cancer models enhances NK-cell-mediated tumor control, particularly in combination with TIGIT or PD-1 inhibition, positioning CD96 as an emerging immuno-oncology target. CD96 also participates in NK-cell adhesion to endothelial cells via interaction with CD155 during diapedesis.