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.[7]
Clinical significance
CD160 is a ligand for HVEM, and considered a proposed immune checkpoint inhibitor with anti-cancer activity along with anti- PD-1 antibodies.[8] 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.[9]
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. doi:10.1038/sj.jid.5700680. PMID17218942.
