– Killer cell lectin-like receptor subfamily F member 1 (KLRF1) is known as NKp80. Human NKp80, a member of the C-type lectin family of proteins (1 – 3), is 231 aa in length with a 38 amino acid (aa) cytoplasmic region, a 21 aa transmembrane region, and a 172 aa extracellular domain (ECD). The protein strongly expressed in peripheral blood leukocytes and spleen, with weaker expression in lymph node and adult liver, and no expression detected in bone marrow, thymus, and fetal liver. Its’ function involved in the natural killer (NK)-mediated cytolysis of PHA-induced lymphoblasts.