NKG2-A/NKG2-B Type II Integral Membrane Protein contains 1 C-type lectin domain and belongs to the killer cell lectin-like receptor family. The killer cell lectin-like receptor family is a group of transmembrane proteins preferentially expressed in NK cells. Natural killer (NK) cells are a distinct lineage of lymphocytes that mediate cytotoxic activity and secrete cytokines upon immune stimulation. CD94 (Cluster of Differentiation 94), also known as killer cell lectin-like receptor subfamily D member 1 (KLRD1), is expressed on the surface of natural killer cells in the innate immune system. CD94 Plays a role as a receptor for the recognition of MHC class I HLA-E molecules by NK cells and some cytotoxic T-cells. CD94 Can form disulfide-bonded heterodimer with NKG2 family members. The CD94/NKG2 complex, on the surface of natural killer cells interacts with Human Leukocyte Antigen (HLA)-E on target cells.