CD160 is a 27 kDa glycoprotein which was initially identified with the monoclonal antibody BY55. Its expression is tightly associated with peripheral blood NK cells and CD8 T lymphocytes with cytolytic effector activity. The cDNA sequence of CD160 predicts a cysteine-rich, glycosylphosphatidylinositol-anchored protein of 181 amino acids with a single Ig-like domain weakly homologous to KIR2DL4 molecule. CD160 is expressed at the cell surface as a tightly disulfide-linked multimer. RNA blot analysis revealed CD160 mRNAs of 1.5 and 1.6 kb whose expression was highly restricted to circulating NK and T cells, spleen and small intestine. Within NK cells CD160 is expressed by CD56dimCD16+ cells whereas among circulating T cells its expression is mainly restricted to TCRgd bearing cells and to TCRab+CD8brightCD95+CD56+CD28-CD27-cells. In tissues, CD160 is expressed on all intestinal intraepithelial lymphocytes. CD160 shows a broad specificity for binding to both classical and nonclassical MHC class I molecules.
CD160 is a ligand for HVEM, and considered a proposed immune checkpoint inhibitor with anti-cancer activity alongside with anti- PD-1 antibodies. CD160 has also been proposed as a potential new target in cases of human pathological ocular and tumor neoangiogenesis that do not respond or become resistant to existing antiangiogenic drugs.
Nikolova M, Marie-Cardine A, Boumsell L, Bensussan A (2002). "BY55/CD160 acts as a co-receptor in TCR signal transduction of a human circulating cytotoxic effector T lymphocyte subset lacking CD28 expression.". Int. Immunol. 14 (5): 445–51. PMID11978774. doi:10.1093/intimm/14.5.445.
Barakonyi A, Rabot M, Marie-Cardine A, et al. (2004). "Cutting edge: engagement of CD160 by its HLA-C physiological ligand triggers a unique cytokine profile secretion in the cytotoxic peripheral blood NK cell subset.". J. Immunol. 173 (9): 5349–54. PMID15494480. doi:10.4049/jimmunol.173.9.5349.
Abecassis S, Giustiniani J, Meyer N, et al. (2007). "Identification of a novel CD160+ CD4+ T-lymphocyte subset in the skin: a possible role for CD160 in skin inflammation.". J. Invest. Dermatol. 127 (5): 1161–6. PMID17218942. doi:10.1038/sj.jid.5700680.
Giustiniani J, Marie-Cardine A, Bensussan A (2007). "A soluble form of the MHC class I-specific CD160 receptor is released from human activated NK lymphocytes and inhibits cell-mediated cytotoxicity.". J. Immunol. 178 (3): 1293–300. PMID17237375. doi:10.4049/jimmunol.178.3.1293.