Human B7-H6, His tag

B7-H6 is a glycosylated member of the B7 family of immune co-stimulatory proteins. Mature human B7-H6 consists of a 238 amino acid (aa) extracellular domain (ECD) that contains one Ig-like V domain and one Ig-like C1 domain, a 21 aa transmembrane segment, and a 171 aa cytoplasmic domain. The Ig-like V domain mediates 1:1 stoichiometric binding of B7-H6 to NKp30 expressed on NK cells. Ligation of NKp30 by B7-H6 induces NK cell activation and target cell cytolysis. B7-H6 is expressed on a wide range of hematopoietic, carcinoma, and melanoma tumor cells, which is consistent with the detection of NKp30 binding sites on many tumors. The expression of NKp30 ligands on tumor cells correlates with tumor cell sensitivity to NKp30‑dependent cell lysis. B7-H6 is expressed in several tumor cell lines, both in vitro and in vivo, including esophageal squamous cell carcinoma, oral squamous cell carcinoma and breast cancer. but remains undetected in healthy cells thus far, and is therefore an excellent tumor marker.