Ready-to-use ELISA kits are available for the detection of KKA3, an alias of the protein, killer cell immunoglobulin like receptor, two Ig domains and short cytoplasmic tail 4. The official gene symbol is KIR2DS4. The protein, with a mass of 33.6 kDa and length of 304 residues, is reported to be membrane-associated. It is a member of the Immunoglobulin superfamily and may be known by other names, including: natural killer-associated transcript 8, killer inhibitory receptor 4-1-2, KIR antigen 2DS4, CD158 antigen-like family member I, and killer cell immunoglobulin-like receptor 2DS4, and p58 NK receptor CL-39/CL-17.